Issue 1.1 (12/07)

Antifouling System Operational Manual

Customer Name CORODEX

Customer Order Number

Cathelco Reference Number CA36860

Project Seawater supply system to Lidos

Ship owner name

Vessel hull number

Cathelco Ltd Marine House, Hipper Street South

Chesterfield S40 1SS, United Kingdom Telephone +44 (0) 1246 246700

Fax +44 (0) 1246 246701 Email: technical@cathelco.com

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SECTION 1 Introduction

1.1 Project identification This manual refers to a Cathelco marine salt water pipework anti-fouling (A/F) and corrosion suppression (C/S) installation. A combined system is referred to in short as an A/F system.

1.2 Cathelco contact data For technical matters, Tel +44 (0)1246 246700 Fax +44 (0)1246 246701 Email: technical@cathelco.com For parts and component replacement quotations and purchase, Tel +44 (0)1246 246700 Fax +44 (0)1246 246701 Email: sales@cathelco.com Please refer to the Cathelco website, www.cathelco.com for any additional contact information.

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1.3 Definitions Anode The electrode through which direct current enters an

electrolyte.

A/F, C/S Anti-fouling, corrosion suppression. An A/F system can also have C/S components.

Cable tail A double insulated cable, generally 2 metres long, connecting an anode to a junction box.

Cathode The electrode through which direct current leaves an electrolyte.

Client The purchaser of the equipment or service.

Contractor The shipyard or other party responsible for installing the equipment.

Earth In metal ships, the ship’s structure is the earth, also known as ‘ground’.

Earth Fault An unintentional connection between a live conductor and earth.

Electrolyte

A liquid in which electric current flows by the movement of ions.

FSR Field service representative. An engineer or technician authorized by Cathelco to commission a new system, and to carry out tests and repairs on Cathelco equipment

Inspection Authority A classification society and/or other organization having responsibility for compliance with the applicable ship safety regulations.

Peripheral A sensor such as a flow switch, valve, on-off proximity switch, pump on-off contact, which activates a relay in the control panel.

Sleeve A permanent watertight fitting in which anodes are mounted.

Stud A solid or hollow threaded steel bar forming part of an anode, by which the anode is fastened into its sleeve.

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1.4 Application The generic parts of this manual apply to all commercial steel hulled vessels, including military vessels where commercial standards are specified, and semi-submersible MODU’s. They may not apply to combat military vessels where shock test or other special requirements are specified, stationary offshore or onshore installations, or jack-up MODU’s.

1.5 Safety Cathelco equipment is sold on the assumption that personnel handling, installing, operating or repairing it obey the safety rules of their workplace. In addition, this manual highlights specific safety warnings in the appropriate sections, and it is VERY IMPORTANT that these warnings be heeded.

1.6 Approvals (and certification) Cathelco operates under ISO 9001:2000 Quality Assurance standards and the Lloyd’s Register of Shipping approved manufacturer scheme. Not being essential to the ship’s continued operation or survival, the components of a Cathelco system are not normally individually approved or certified. Component certification by a Class or other authority surveyor can be arranged at extra cost and with reasonable notice.

1.7 Liability Cathelco’s liability in warranty claims is limited to the value of the goods supplied.

1.8 Warranties Standard warranty is for 12 months from the date of commissioning, provided that the system is fully commissioned by a Cathelco Authorised Service Engineer and a signed copy of the Commissioning Check List sent to Cathelco. In order to meet the warranty requirements it is essential that monthly log sheets are recorded and returned to Cathelco. Failure to follow the instructions in the manual can void the warranty.

1.9 Intellectual Property The contents of this manual and all drawings associated with it are protected by copyright and intellectual property law. They should only be reproduced for purposes in connection with installing or operating Cathelco equipment. The word “Cathelco”, whether capitalized or not, is registered by Cathelco Ltd. as a trade mark or brand name in many but not all maritime jurisdictions. In this manual it is simply used as a convenient abbreviation for the company name, Cathelco Ltd.

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SECTION 2 System Specification

2.1 Scope of supply and weights as supplied by Cathelco Cathelco Reference number:

Qty Description Cathelco Part No

Weight. Each/kg

Total Weight/kg

10 Dual Anode TBA TBA TBA

8 Copper Anode TBA TBA TBA

8 Aluminium Anode TBA TBA TBA

18 Stainless Steel Cathode TBA TBA TBA

4 EB/CC/4 Way control Panel TBA TBA TBA

10 EB/CC/2 Way Control Panel TBA TBA TBA

Total nett weight of system kg

Supplied by Client/Contractor Mating flanges. Cables from control panel to junction box and vessel alarm system. Vessel’s alarm system Power supply cable Earth return cables Power source required 220V AC 50/60Hz 1Phase

2.2 System size calculation Sea Water to be Treated 8 Chambers flow rate = 180 m3/hr 6 Chambers flow rate = 270 m3/hr

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Anode Location Copper & Aluminium Anode in each Pump Chamber Anode Life/Renewal 2 year When re-ordering please quote Drawing No. A3917/A3918/A3919 – CA36860 and the anode part number from table 2.1

2.3 Current Settings The current settings which appear below should be used in most circumstances. If, however, there continue to be signs of fouling, refer to Section 5.2 for guidance on current settings.

Seachest Anode Ref

Anode Size In Operation Current Settings

± 0.02

Not In Operation Current Settings

± 0.02

Dual Purpose Anodes

MG 1 WVR 17 0.90 amps 0.40 amps

TC 1 WVR18 0.90 amps 0.40 amps

Single Anodes

MG 2 WVR 17 1.40 amps 0.40 amps

TC 2 WVR18 1.60 amps 0.40 amps

The higher the current setting the shorter the anode life. The lower the current setting the greater the anode life.

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Installation Spares Each new system is supplied with an Installation Spares Kit with spares which are specific to the equipment that has been supplied. These spares are for use during the initial fitting only. On Board Spares - Consumables 2 off fuses for control panel modules and 2 off fuses for control panel power unit, spare fuses fixed to inside rear of control panel casing.

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SECTION 3 The Principles of the Cathelco System

3.1 The problem The settlement and growth of marine life forms in salt water piping systems in ships and other marine installations can be very costly. The resulting problems include overheating and possible shut-down of machinery, accelerated corrosion, and reduced firefighting capability. The flow velocity and temperature in these systems are more often than not ideal for encouraging the larvae of marine animals to enter the adult stage after they have passed through the inlet strainers, and settle on the available surfaces of pipes, heat exchangers, valves, etc. The most common culprits are blue mussels, barnacles and tubularia. It is not practical to filter out the tiny spores and larvae of these creatures, thus filtration has to be supplemented with water treatment.

3.2 The Cathelco solution 3.2.1 Basic principle Cathelco anti-fouling systems are based on the fact that the main fouling organisms can be inhibited from growing by the introduction of very small quantities of copper into the water. The required dosage per litre is only a few parts per billion. This amount is of the same order of magnitude as the copper content in a typical sample of sea water. Copper is introduced into the water flow by electrolysis, in the form of positive ions. Thus the principle is known as copper ion generation, or CIG. Sea water is a good electrolyte, and a low DC voltage is sufficient to provide the necessary current. Figure 1 shows the electrolysis circuit in its simplest form.

Figure 1 - Basic Circuit

-+ Cathode Anode

D.C. Source

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In the simplified circuit with a copper anode, the cathode would in time become copper plated, and this effect can indeed be observed with Cathelco systems when there has been zero flow for a significant period. In practice, the majority of Cathelco systems are arranged as shown in Figure 2.

Figure 2 - Typical Seachest Arrangement

The negative conductor from the power source is connected (earthed) to the ship’s structure, which is in effect the cathode. The ions are carried by the water flow through the piping system. The copper ion concentration can still be high enough to to inhibit the targeted marine growth one hundred meters or more from the anode. 3.2.2 Corrosion suppression With Cathelco systems, it is relatively simple and economic to supplement the anti-fouling function by adding corrosion suppression (C/S) anodes. They are energized by the same control panel as the anti-fouling (A/F) anodes, as shown in Figure 2. Experience has shown that by consuming the C/S and A/F anodes at the same rate by volume (with the convenience that all anodes are ready to change at the same time), substantial corrosion suppression is gained. In the case of ferrous piping, the C/S anodes are aluminium, and with cuprous piping they are iron. The Al anodes emit aluminium hydroxide ions, which form a protective coating on the inside of the pipes. Cuprous pipes ( CuNi, CuNiFe, AlBro) are much more resistant to sea water corrosion than steel, but are nevertheless susceptible to what is known as impingement corrosion. The iron anodes emit ferrous ions, which give significant protection from this form of corrosion. Marine engineers are familiar with the use of iron or steel “sacrificial” anodes fitted in the headbox of a shell and tube

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condenser having cuprous tubes and tube sheets. The Cathelco anodes perform the same function, the only difference being that they are “live”, with a controlled rate of ion emission.

Although it is extremely unusual, some vessels have aluminium sea water piping (AlBro is acceptable, see above). Cathelco A/F and C/S systems should not be installed in such cases.

3.2.3 The control panel Depending on their design, Cathelco control panels require a range of supply voltages:-

• 110 volt single phase AC • 220 volt single phase AC • 12 -24 volt DC

AC power is transformed and rectified to a 0 – 12 volt DC output. The output voltage is automatically adjusted to maintain a constant current to each of a number of anodes. In general, each anode is controlled individually. The great majority of systems work with a current range of 0 – 2 amps per anode, manually adjustable in 0.2 amp steps. Using a conservative figure of 50% for panel efficiency, input power per anode can not exceed 48 watts. In practice, the power consumption of a ten anode panel will seldom exceed one quarter of a kilowatt. A/F panels are dust and spray tight to IP65, and are thus suitable for mounting in machinery spaces not too far from the anodes which they control. 3.2.4 Current reduction relays (Optional) As an optional extra the current setting can be modified automatically using peripheral devices such as flow switches, pump starter contacts, and valve open/close contacts. The peripherals are wired to current reduction or on/off relays in the panel which modify the current to the relevant anodes. The relays can also be manually activated by “HI-LO” switches mounted on the panel for convenient re-setting of the anode currents from seagoing to harbour sea water flow conditions and vice versa. Some installations include a slave panel with appropriate indicator lights, mounted in a convenient location from which the main panel(s) can be switched on or off or between HI and LO conditions 3.2.5 System variations The seachest mounted anodes illustrated in Figure 2 are the preferred arrangement and the one used on the majority of installations. It is usually simpler than the alternatives, and, as well as protecting the seachest much more effectively than anti-fouling paint, it introduces the ions at the furthest upstream point in the pipe run, thus ensuring uniform dosage of the water regardless of its destination. The disadvantage is

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that anodes fitted in seachests can only be changed with the vessel in dry dock, or in the case of top mounted anodes by sealing off the chests with diver installed patches. With the trend to five year docking intervals, or in the case of retro-fits, it can be undesirable or physically impossible to fit sufficient quantity/size of anodes in the seachests. The alternative locations for the anodes are :

• In the intake strainers (Figure 3) • In the intake pipes on large vessels (Figure 4) • In the “electrolysis tanks” (Figure 5)

In the case of an electrolysis tank, a source of sea water with sufficient head delivers water through the tank where it is dosed and injects it in the main intake(s). The dosage is of course calculated for the total flow through the pumps, but can be at a far higher concentration in the electrolysis tank loop, in order to keep the pipe size down. Up to one hundred times the concentration is acceptable.

Figure 3 - Strainer Installation

Seawater out

2 core cable from panel

Junction box

Typical strainer installation showing weld-in sleeve. The sleeve can be nylon. Metallic strainer assumed, which must be well earthed.

Weld-in sleeve

Strainer basket

Seawater in

Anode

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Figure 4 - In-Line (Pipe) Installation

Figure 5 - Electrolysis Tank

3.2.6 Anode Types Cathelco produces a variety of anode types. See section 4 of this manual for the full range of standard anodes and mountings. Combination A/F and C/S anodes on the

Earth return

Seawater in

Seawater out

Seawater in

Seawater out

Anode

Cathode

Pipe upstand and flange sleeve must be used.

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same stud are available for restricted space applications, and mounting sleeves are available for installation of new anodes from the ‘wet’ or the ‘dry’ side. 3.2.7 Corrosion/Fouling Suppression in Seachests. Generally at drydocking of vessels with seachest mounted anodes, the anti-fouling paint shows very little deterioration and the sacrificial anodes in the chests are only partially used. Nevertheless, Cathelco recommends fitting sacrificial corrosion protection anodes and applying anti-fouling paint. This is to give protection in areas of the chest with little or no flow, or where dedicated cathodes are fitted, or in case of premature depletion of the anodes. 3.2.8 Fresh or Brackish Water Operation. The standard control panel maximum output voltage is usually sufficient to operate the anodes at full current in water with up to two or three times the resistivity of standard ocean water, or about 75 ohm-cm, which includes many estuarial and coastal waters. However, in truly fresh water the system will go to maximum voltage with little or no current output, and it should be switched off if this situation lasts more than a few days. See also Section 5 of this manual. In brackish or very dirty water the same results may been seen which include a drop in output current. This will rectify itself once the vessel is back in seawater. 3.2.9 Effect on Hull Cathodic Protection In a typical Cathelco system, the effect of using the hull structure as part of the return (negative) path for the anode current is to reduce the hull potential with respect to a standard reference cell. In other words, it is reinforcing the function of the hull cathodic protection system, be it by impressed current (ICCP) or sacrificial anodes. Usually, the effect is insignificant, but in very large A/F installations the reduction can amount to a few tens of millivolts, and where owners prefer not to have the systems interact, Cathelco can supply dedicated cathodes which are isolated from the hull (see Figure 6).

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Figure 6 - Dedicated cathode arrangement

3.3 Forms of Fouling not Controlled by Cathelco Systems Seaweed and grass are not affected, and have to be cleared from the intake strainers when they proliferate. Certain algae and “green slimes” are not affected, but these do not build up and block pipes in the way mussels do, as they require light for growth.

3.4 Treatment of Feed and Process Water The copper (and aluminium or ferrous) ions generated by the CIG process do not carry over with the condensate in evaporative type fresh water generators, or pass through the membranes in reverse osmosis units. The CIG process is approved by the UK Ministry of Health for feed water in potable water makers. While the addition of copper in the same order of magnitude as that already in sea water is enough to prevent transition of shell fish and mollusks from larvae to adults, it will not affect the adult animals. CIG treated water is used in holding tanks for adult shrimp, clams and lobster with no noticeable ill effects.

3.5 Dosage Rates and Anode Life Cathelco engineers will recommend the number, size and disposition of anodes in a new A/F system based on the sea water piping schematic, pump capacities, and the

_ +

Seachest top

Anode Anode

Stainless Steel Cathode The Anodes and the Cathode are isolated from the hull

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vessel’s trading pattern (including port time, fresh water sailing time, and drydocking interval). The current settings, which in turn determine the rate of depletion of the anodes, will be specified to give reasonable assurance of fouling control, but because this is not an exact science, anodes will generally be sized with a margin to allow the user to increase current if some fouling is still experienced. Clearly, when a vessel’s main engines are not running there is a significant reduction in sea water cooling requirement, and in the case of port stays lasting over 24 hours, the current settings can be reduced. This reduction can be accomplished manually, by adjusting current to each anode or by a master switch controlling all affected anodes through relays; alternatively it can be controlled automatically through relay(s) activated by contacts in the relevant pump starters. See also Section 3.2.4.

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SECTION 4 System Installation

4.1 Handling and Storage Cathelco components are shipped in substantial wooden boxes; however they are not weather tight and the boxes and their contents should be stored indoors until needed at site. On receipt, the boxes should be opened and the contents checked against the documentation.

Normal care should be exercised in handling anodes and panels. On no account must anodes be lifted by their cables. Weld-in and flange type sleeves are supplied unpainted, but with a rust prevention coating. This coating must be removed using white spirits or turpentine before installation. If anodes are installed in a space where blast cleaning or painting is not finished, they must be suitably protected. Before flooding the spaces, check to ensure that the protection has been removed, and remove any paint, tape adhesive residue or grease from the anode surfaces.

4.2 General Anode Positioning Instructions It is important that anodes are mounted in the vertical position unless otherwise stated on the Cathelco drawings for specific vessels. Do not apply any mechanical load to anode cable. Where anodes are seachest mounted they must be positioned in the direct flow of seawater from the inlet grids to the main seawater suction pipe. (Refer to Figure 20) The mechanical and electrical installation work must meet the standards of the inspection authorities. The contractor is responsible for arranging on site drawing approvals and inspections at their cost. Cathelco will supply equipment approval certificates at extra cost if covered in the customer’s purchase order, to the extent that authorities are willing to issue certificates. See also Section 1.6 of this manual. Determine which type of mounting is appropriate for your system (refer to specific project data) and then follow the relevant instructions.

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4.3 Mechanical Installation The housings in which the anodes are mounted are known as sleeves. Each sleeve, irrespective of type, is fitted with a mounting sleeve lid/safety cap which is pressure tested to 100 psi. These are approved by Lloyd’s and the UK Dept. of Trade and Industry. The cap is supplied with a water tight cable gland. If the anodes have been installed using metal sleeves, they should be painted to the same specification as the strainer/seachest/tank. 4.3.1 Submersible Anodes These are available in a variity of different sizes and are designed to fit in confined areas with small flow rates. They come in two different diameters and different lengths depending upon the installation area and flow rates. There are two main types as follows:-

Figure 7 - Submersible Anodes

Submersible anode These are fully sealed units and the cable used is suitable for use in sea water. They can be either mounted into the top of strainers or submerge mounted inside strainer baskets, especially where deep cylindrical or conical shaped strainer baskets are used. A 32mm dia hole needs to be drilled in a strainer lid or mounting flat to accommodate the anode. The anode should be inserted from underneath and secured with 2 nuts on the top side using a pin spanner. Submersible cathodes These are available where a dedicated earth return path is required, again these can be submerge mounted. A 32mm dia hole need to be drilled in strainer lid or mounting flat to accommodate the anode. Insert the anode from underneath side and secure with 2 securing nuts on the topside.

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Installation of submersible anodes with nylon mounting in strainer lid. The unit is fitted directly to the strainer lid through a 32mm diameter hole. The strainer should be flat (and free from paint and burrs) on the top and bottom surfaces to ensure that the ‘O’ ring fits with a water tight seal to the underneath of the strainer lid. Ensure that the anode is located inside the strainer basket. It is important that the anode does not touch any metallic components and in certain cases it may be necessary to remove or relocate the strainer basket lifting bar. Ensure that the ‘O’ ring is fitted in the bottom insulation washer and in contact with the strainer lid.

1) Determine the position of the anode mounting and 32mm diameter hole in strainer lid to suit. This is usually the dead centre when only one anode is used per strainer.

2) Fit the anode from underneath and secure with nylon nut using a pin spanner.

3) Fit or weld earth stud to either strainer lid or strainer body and attach earth cable. See wiring diagram in Section 9 (or connect to cathode if required).

Installation of anodes with nylon mounting for submerged mounting

1) A suitable bracket must first be made and fitted to the strainer basket which must be a minimum of 50mm x 3mm thick. The bracket can be welded or bolted to the strainer basket.

2) Determine the position of the anode mounting sleeve and drill 32mm dia. hole in bracket to suit. This is usually in the dead centre of the bracket. Ensure the anode does not touch any steelwork or other metal objects in the locality

3) Fit anodes as for strainer lid mounting. 4) Lower basket into seawater intake. 5) Fit cable gland, suitable for cable size, in strainer lid. 6) Pass the cable through the gland and secure gland. Replace strainer lid. 7) If submersible cathodes are supplied they should be fitted in the same way

as submersible anodes.

4.4 Anodes – Installation and Positioning Generally a given installation will have anodes of more than one size and material. The system diagram in Section 9 indicates the type and size of anode at each location. The Cathelco system diagram does not show structural details or the precise location and orientation of each anode. Sometimes the contractor will make working drawings showing such details, but even in those cases careful measurements should be made to ensure that the anodes and sleeves can be installed as shown.

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In locating anodes the following points must be taken into consideration: For orientation more than 30 º from the vertical, Cathelco should be consulted, see Figure 17.

• With weld-in sleeves, the clearance for inserting the anode must be its full length including the stud. See Figure 18.

• With flanged sleeves, the clearance must be more than the distance from the end of the anode to about 30 mm above the top of the cable gland. See Figure 19.

• Anodes must not be located in a “dead” space, but as nearly as possible in the direct flow path of the water from the inlet grids to the sea water suction pipes. See Figure 20

• In order to prevent uneven burn-off of the anode, structural members must not be nearer to the anode surface than shown in Figure 21. Where this amount of clearance is a problem, Cathelco should be consulted.

• Before cutting and welding, it is advisable to have the location and orientation agreed to by Cathelco’s on-site representative.

Figure 8 - Anode Orientation

Consult Cathelco if angle is greater than 30 degrees.

Most anodes can be mounted up to 30 degrees from the vertical as shown on the right. Shorter anodes may be mounted horizontally after prior agreement with Cathelco.

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Figure 9 - Clearance for Weld-in Sleeves

Figure 10 - Clearance For Flanged sleeves

The installation of flanged sleeve anodes usually requires clear access from above to allow for the use of lifting equipment. L= Required clearance for installation with flanged sleeves

Obstruction

Seawater out

L= Required clearance for installation of weld-in sleeves

The diagram shows the clearance required in the seachest for installing and replacing anodes when using weld-in sleeves.

Anodes should be mounted in the main flow of seawater from the inlet grids to the seawater suction. Anodes should not

Without grating. Do not mount anode here. Even with inlet grating, avoid mounting anode in this space

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Figure 11 - Mounting Anodes in Direct Flow (Plan View)

If possible, mount anode in this space.

Seawater Out

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Anode Dia./Mounting ‘A’ ‘B’ ‘C’ ‘L’

82.5 Weld in sleeve 150 150 160 500

120 Weld in sleeve 250 250 220 500

DN/JIS100/4”flange 150 300 50 min 350 + anode length

DN/JIS100/6”flange 250 450 50 min 400 + anode length

Cofferdam 250 450 50 min 400 + anode length

‘A’ = Distance from centre of anode to nearest steelwork. ‘B’ = Distance across centres of anodes. ‘C’ = Clearance from bottom of anode to seachest bottom Min. ‘L’ = Clearance top of anode mounting to nearest obstruction. (Refer to Figure 19)

Figure 12 - Clearance from Structural Members

The above are recommended minimum distances. In some circumstances they may be reduced, but it is essential to consult Cathelco before installation.

See table below for minimum acceptable distance from structure.

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4.5 Control Panels

Modular – EL/DD Mini – EB/CC 4 Way Small Boat EB/SB 2 Way Nano EB/NS Cathelco A/F panels are dust and spray proof to a minimum rating of IP65, and can be located in machinery spaces. The IP65 rating must be preserved by using spray tight strain relief glands for cable entry. The contractor must make a robust structural frame to which the panel will be bolted. Bolt size and spacing are shown on the panel drawing in Section 9 of this manual. The panel should be located at about eye level, with convenient and safe access for adjusting currents and servicing. The door on type EB/** panels, and the whole hinged module section on type EL/**/** panels must be clear to swing out at least 90 degrees. It is highly recommended that EL/DD/ and EL/4D/ type panels are mounted on the horizontal brackets shown on the panel drawing. These give additional support, particularly when the module section is open. Cathelco also recommends gluing a 5 mm thick strip of rubber to the top of the bracket to give greater protection to the front door and mid-section of the panel. The contractor shall punch or drill the control panel gland plate with the correct size holes (or use the pre-punched holes in EB/** type panels) and supply and fit glands to the required standard. For panels with swing out module sections, care must be taken to leave sufficient length of cable between gland and terminal block to swing the module section through at least 90 degrees. Control panels must be earthed to the ship’s structure. Generally the mounting bolts will perform this function satisfactorily. This can be checked by carrying out a continuity test between the panel casing and the ship’s structure. After fitting, check that the panel is set for the correct voltage. Type EL/DD and EL/4D panels have a switch at the back of the supply power module that can be toggled between 115 and 230 volts. Type EB/CC panels have a 115/230 switch accessible from the front. Type EB/SB and EB/NS panels take either a 12V or a 24V DC supply and are auto-sensing.

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Type Modular Input Voltage

Max no. Modules

Max Anodes

Max Output Per Anode

Fuse (Power)

Fuse (Anode) Weight

EL/DD/** yes 220/110 AC 4 per row 8 per row 2 A 2.5 A or

5A 3.15 A 25kg+

EL/4D/** yes 220/110 AC 4 per row 4 per row 4 A 2.5 A or

5A 6.3 A 25kg+

EB/CC no 220/110 AC N/A 4 2 A 2.5 A 3.15 A 5-8kg

EB/SB no 24/12 DC N/A 4 1 A 5 A 1.6 A 4-4.6kg

EB/NS 1-2 no 24/12 DC N/A 4 0.5 A 2.5 A 630 mA 2.5-3kg

EB/NS 3-4 no 24/12 DC N/A 4 0.5 A 5 A 630 mA 2.5-3Kg

Figure 13 - Control Panels

For details of the specific equipment supplied for your installation, please refer to Section 2 and the drawings which appear at the back of the manual.

4.6 Electrical Installation 4.6.1 Cable Sizes and Types Cathelco supplies each anode with a minimum of 1.5 metres of double insulated single conductor cable (longer if ordered by the client). For ease of identification, cables supplied as part of anode assemblies are coloured as follows:-

Anode Type Cable Colour Coding

MG (Copper) Red Outer/Red Inner PVC covering OR Grey Outer/Brown Inner PVC covering

TC (Aluminium) Black Outer/Black Inner PVC covering OR Grey Outer/Blue Inner PVC covering

FE (Cast Iron) Black Outer/Black Inner PVC covering OR Grey Outer/Blue Inner PVC covering

For Dual Purpose Anodes and smaller Nano Type Anodes refer to drawing for cable specification.

Figure 14 - Cable Colour Coding

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All other cables in the A/F system are to be supplied by the contractor. Cables and their insulation must be of a type approved by the inspection authorities for their location, voltage and temperature. In order to achieve acceptable voltage drop, and based on not more than four anodes per earth return conductor, Cathelco recommends the following conductor sizes for the anode circuits:

Length of cable run/m

Minimum conductor DD modules up to 2 amps output.

Minimum conductor 4D modules up to 4

amps output.

Metric AWG Metric AWG

0 - 25 2.5 sq.mm 14

4 sq.mm

12

25 - 50 4.0 sq.mm 12 6 sq.mm 10

50 - 100 6.0 sq.mm 10 10 sq.mm 8

Figure 15 - Cable Supply Sizes

Cable for the power supply should not exceed 2.5 sq.mm2 with a minimum of 1.0mm2 core. Oversize cables should be avoided, as they are likely to cause mechanical overload on the terminal blocks. For signal circuits from peripherals to relays, 1.5 sq.mm or AWG 16 will generally suffice, regardless of length. See Section 4.11

4.7 Cable Installation Proximity to other cables, cable clip spacing, and mechanical protection in vulnerable areas, shall all meet with the approval of the inspection authorities. The Cathelco supplied anode cables shall be connected to the system wiring in water tight junction boxes, located as far above the bilges as practicable. In the case of solid stud anodes, make sure the anode cable is tightly secured to the top of the stud using the 6 mm cap screw. To avoid malfunctioning of the system due to leaky glands or condensation, Cathelco recommends packing the sleeve cavities and junction boxes with petroleum jelly or non-conducting silicone grease.

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After packing the sleeve cavity and screwing on the safety cap, tighten the gland, making sure there is no mechanical tension on the cable. Cathelco recommends that all cables be tagged. Future troubleshooting can be simplified if a marked up copy of the Cathelco wiring diagram or a contractor’s working drawing with the tag numbers identified, is placed in the back of the control panel. This drawing should also show the supply distribution panel number and circuit number.

4.8 Power Supply Each AC panel should have a properly identified dedicated single phase supply circuit, protected by a fuse or circuit breaker. The supply cable shall have three conductors, phase, phase or neutral, and earth. The fuse/circuit breaker rating must not be less than the maximum input of the wattage divided by the voltage. In most cases a 10 amp rating will suffice, although 15 amps is commonly the smallest available. In any case, the ampacity of the supply cable must exceed the fuse/breaker rating. DC panel supply cables should be two conductor with an ampacity of 10 amps.

Panel Type

2 Amp Module

4 Amp Module CC SB NS

Power Consumption/ Per Channel (No of anodes)

30 VA Per Channel (60 VA Total)

60 VA 30 VA 20 Watts Per Channel

12 Watts Per Channel

Figure 16 - Power Consumption

4.9 Peripheral Circuits In most cases a two conductor 1.5 sq.mm cable will suffice for connecting a peripheral to the corresponding relay in the panel. If Cathelco are not supplying or specifying the peripheral, they should be informed of its specifications.

4.10 Testing Final testing of the system is described in Section 7, Commissioning. Before installing hollow stud anodes, the resistance between the anode and the stud should be checked using a multimeter. It should be infinity for a dry anode before it has been fitted in situ. Cable run integrity should be checked before the system is flooded, with the anode supply and return cables disconnected at the panel. Once the anodes are connected, their circuit resistance to earth must be checked using a multimeter only, a meggertester voltage is too high.

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SECTION 5 Operating & Maintaining a Cathelco A/F System

5.1 Daily Supervision Cathelco recommends recording the current readings, or at least deviations, for each anode daily or Weekly on a log sheet. This will ensure that anomalies can be dealt with promptly, and reduce the chance that crew will forget to adjust from ‘in use’ to ‘not in use’ settings. A standard copy of the log sheet can be downloaded from the Cathelco website. All log sheets can be sent to Cathelco for analysis free of charge. They should be emailed to aflogsheets@cathelco.com This is important because the record of the current settings will help in determining the cause of any problems that might arise. If one of the current settings is showing zero and cannot be adjusted, or there are any other problems with system, please see Section 6 of the manual. If the cause of the problem cannot be found, please contact Cathelco for further assistance by emailing technical_af@cathelco.com As part of the daily supervision, check that all the digital display ammeters are working. When an anode has nearly wasted, the corresponding display will start to fall. When this happens, turn the anode current knob back to zero and leave it until the anode renewal. Reset once again at sea after renewal to the previously given current settings.

5.2 Current Settings Section 2 of this manual gives the recommended current setting for each anode. The effective working of the system can only be determined by inspection and it is suggested that if after 6 months of operation the opportunity to examine a strainer, length of pipe or heat exchanger, presents itself, this should be done. This routine can be repeated at intervals, the current being adjusted accordingly. The seagoing current settings are adjusted manually. If there is evidence of mussel or other marine growth beginning to appear in strainers or heat exchangers, adjust this setting for the copper (A/F) anodes upwards in increments of 0.2 amps until new growth ceases to appear. Each increment should be left set for 30 days before further adjustment up or down. See also Section 6. For installations in which current reduction is not automatically controlled by peripherals, adjustment to the ‘not in use’ settings given in Section 2 must be made manually. Cathelco recommends doing this whenever a port stay, with the main sea water circulating pumps shut down, lasts more than 24 hours or whenever a sea chest is not in use.

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5.3 Anode Life Since Cathelco has no control over anode current settings after a system has been commissioned, anode lifetime cannot be guaranteed. In the case of newbuilds at shipyards located in fouling prone areas, it may be desirable to operate the system during the outfitting afloat stage. Owners must takes this period into account when estimating the time to re-order anodes.

5.4 Seawater Supply Management The assumption in determining anode current values is generally that all sea valves, except for high suctions for use in shallow muddy or sandy water, are normally open, and only closed during strainer cleaning. Any departure from this mode of operation may lead to insufficient dosing in some seawater systems. Some operators have found that where dosing appears to be insufficient, and overheating of engines is not a problem, light growth can be stopped by recirculating dosed seawater to the seachests instead of overboard. This can avoid increasing current settings and shortening anode life.

5.5 Anode Change/Replacement Only genuine Cathelco anodes/parts should be fitted. Using anodes/parts supplied by other manufacturers will invalidate the Cathelco warranty.

Most anodes are available from stock. Nevertheless it is recommended that Cathelco be given 4-6 weeks notice for supply of replacement anodes. The Cathelco reference, vessel name and anode reference should be quoted when ordering replacements.

The system must be switched off before any work is carried out on the anodes.

All anodes are sacrificial anodes and will be consumed after a period of time. Seachest mounted anodes must be replaced at every dry docking. Anodes mounted in-board of a sea valve (i.e. in strainers) can be replaced as required. For the majority of installations where a mounting sleeve has to be used, the procedure below should be followed.

1. Slacken the sleeve gland nuts, back off the sleeve safety caps, and disconnect the tail cables at the anode or the junction box as appropriate. Remove the spent anodes using the appropriate box spanner.

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2. In the case of cofferdams, the top flange should be removed to allow access.

Then the cable should be disconnected from the anode before the whole assembly is removed from the seachest.

When removing nuts from the anode mountings, care must be taken to prevent the remaining part of the anode from falling through the seachest, creating a risk to personnel, or damaging the bottom of the seachest.

3. Once removed, thoroughly clean the sleeve cavities and install the new anodes

as indicated in Section 4 of the manual. Fit new ‘O’ rings and gland grommets. Submersible anodes Cables should be disconnected from the junction box/anode top as appropriate. The securing nuts should be undone as required and the anodes removed. In the case of anodes with integral cathodes, the remains of the copper anode should be unscrewed from the stud and whole assembly removed. After installation, perform the same dry and afloat tests as for a new system installation.

5.6 Routine Maintenance Cathelco anti-fouling systems are rugged, relatively simple, and very reliable if installed correctly. No routine preventative maintenance is required between anode changes. If a Cathelco representative is not present to supervise the anode change, a responsible technician should inspect the panel(s) for cleanliness and check the fastenings, as well as performing commissioning checks/installation tests. Fault finding is dealt with in Section 6 of the manual.

5.7 Maintenance of electrolysis (treatment) tank systems To ensure that electrolysis tank systems stay in good working order it is essential that they are cleaned on a regular basis.

1) The air vent should be opened daily to prevent air pockets inside the tank.

2) The tank should be cleaned out to remove anode floc at least once every 2 months including a drain off operation, if necessary, as follows:-

a) Turn of main power in control panel.

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b) Close inlet valve of anode treatment tank and open drain valve. c) Remove hydroxide that has settled inside the tank.

3) The water strainer and flow meter on the sea water flow pipe should be cleaned out to remove anode floc every 2 months.

4) The valves for the not-in-use seachests should be closed and valves for

the in-use seachest opened to give appropriate flows to each seachest as required.

5.8 Anode renewal in Chambers Anodes need to be replaced when there is only a small amount of copper showing below the heat shrink. Replacement anodes are supplied with all the parts that are necessary for replacing them. It is not necessary to replace the mounting sleeves.

1) Switch off the power to the control panel and pump, then close the inlet and outlet valves to the treatment tank.

2) Disconnect anode and cathode cables from control paenl.

3) Lift lid

4) Disconnect anode/cathode cables in junction box, if required.

5) If the anodes are flange mounted, remove each anode individually from

tank c/w flange mounting.

6) If anodes are weld-in sleeve design, remove the whole tank lid.

7) Loosen cable gland and remove each lid on each sleeve.

8) Remove cable, undo nuts and remove old anodes.

9) If necessary, clean flat surfaces and inside sleeves to remove any unwanted debris, etc.

10) Install new anodes in reverse order making sure the neoprene washer is

on top of the anodes and makes a seal with the underside of the mounting sleeve. See anode replacement sheet for correct torque setting of anodes.

11) The tank should be thoroughly cleaned inside.

12) The sleeve lids and tank lid should be replaced in the reverse order and

secured. Replace gaskets if necessary.

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13) Reconnect the anodes inside junction, if necessary. 14) Close drain valve and air vent valve.

15) Open valves, restart pump and turn on control panel.

16) Open air valve to release any trapped air until water appears, then close.

17) Check current settings on control panel are correct according to the

manual.

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SECTION 6 Troubleshooting a Cathelco A/F System The troubleshooting instructions below should be carried out by a suitably trained person following all the necessary on board safety procedures.

Indication Action Panel running LED does not light up when switching on.

Is there full voltage at panel power terminals?

If yes, check power module main fuse and LED, and rectify as necessary. If no, close switch or breaker at ship’s distribution panel. Check that voltage supply and voltage switch on panel is set to the correct value 110/220V.

Running light is lit, but either all anode alarm lights are lit, or all anodes fail to respond to the full range of their current controls.

Is vessel in fresh water? If yes, check panel condition again on return to salt water (It is best to switch off the system if fresh water passage will last more than a day). If no, it is extremely unlikely that all external anode circuits are faulty. Consult nearest Cathelco technical representative. Are all earth returns fitted? If yes, then check all connections. If no, install earth returns (at least one per seachest/strainer) and connect back to the control panel.

Anode alarm light is lit. Switch off system, open panel, and exchange positive lead for the circuit showing alarm with a good one, and

switch on again. Is alarm light now showing on the other anode control position? If yes, see overleaf.

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Anode alarm light is lit. (continued)

With the positive lead for the suspect anode disconnected at the panel, open up the anode sleeve safety cap and any junction boxes in the circuit, and clean and repair any obvious deficiencies such as loose connections, missing or incorrectly located earth return, or water ingress. Then carry out flooded resistance and potential check as specified in Section 8 of this manual. If test readings are good, reconnect in the original location and switch on system. Anode control should now respond correctly with no alarm light. If test readings are bad or dubious, or anode control still shows alarm condition, the anode is almost certainly fully consumed (which can be verified if it is strainer mounted), and must be replaced at the first opportunity.

Warning! If when slacking off the gland nut on an anode sleeve, water squirts out under pressure, tighten up

immediately, cut the tail cable short to prevent “wicking”, and tape it off.

Water leaks slowly in the sleeve.

It is sometimes possible to stop a leak by tightening the anode stud nuts. For a seachest mounted anode this might not work if the anode rotates. If the leak cannot be stopped, remove the tail cable, replace the safety cap, and plug the gland.

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Marine growth is found in strainers or heat exchangers.

Are current settings according to the manual? If no, readjust the settings and continue to monitor the situation. If yes, increase the copper dosage by adjusting the current to anodes in the affected sea water piping runs upwards by 0.2 amps. After 30 days, open up for inspection and increase the current by another 0.2 amps if growth has reappeared. If the second increase is unsuccessful, measure the actual current in each anode positive lead either by using a multimeter in series or a sufficiently sensitive DC current clamp. The reason for this is that a partial earth fault whose resistance is in the same order of magnitude as the anode circuit resistance will reduce the current passing through the anode while the panel “sees” the total current and the alarm light will not come on. If this proves to be the case, take the necessary steps to eliminate the earth fault, otherwise contact the nearest Cathelco technical representative.

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SECTION 7 Testing and Commissioning a Cathelco A/F System

7.1 Application These test procedures apply to new installations (newbuild or retrofit) and when changing anodes.

7.2 Dry Tests The majority of Cathelco systems are based on seachest location of the anodes, which involves installation before launch for new systems, and during dry docking for retrofit systems. Before the vessel is launched or refloated, check the isolation of each anode from the hull, as well as continuity of the positive feed circuit to the anode.

Megger testers should not be used except on cable runs that are disconnected both from the control panel and the anodes.

With a hand-held multimeter, the resistance between anode cable and hull should be in the mega-ohm range. The actual reading will depend on the make of meter, the polarity, and the presence of any moisture or dirt in the chest. If there is a poor reading, but the cable from the panel to the junction box appears to be intact, disconnect the anode tail cable at the junction box and repeat the check.

7.3 Flooded Tests With the vessel afloat and system flooded with seawater, the integrity of each anode’s circuit should be checked. With the anode (positive) cable disconnected from the terminal block in the controller, the following readings should be taken, using a good multimeter (a Megger tester will not give a valid reading).

Before starting this test, make sure that seachests and strainers are properly vented. It is not unusual for crew or shipyard personnel to miss some vent valves when preparing to flood.

7.3.1 Open Circuit Potential Check The following table shows the expected range in millivolts of the potential between anode and ground. If there are sacrificial anodes in the seachest, or even near it on the shell, the last two columns will apply; otherwise the first will show the upper range of expected values. In the absence of sacrificial anodes in the seachest, the better the paint job and cathodic protection of the outer hull, the nearer the value will be to the right hand figure in the first column of the table. Very low potential difference is likely to indicate loss of continuity or breakdown of insulation of the circuit, except in the cases where anode and hull or sacrificial materials are the same, or very close in the galvanic series. Potential readings are also useful for verifying that anti-fouling and corrosion

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suppression cables have not been crossed over, which is important where different currents are specified.

A/F or A/C Anode

No sacrificial anodes Sacrificial anodes in seachests

MS Zn Al Cu 250-400 (+) 650-900 (+) 600-850 (+) Al 100-250 (-) 100-200 (+) 0 Fe 0-150 (+) 300-400 (+) 200-400 (+)

Figure 17 - Galvanic Potential Ranges in Salt Water

These figures are guidelines only. Actual potentials depend on many variables. 7.3.2 Resistance Check A multimeter can be used to check the resistance between the circuit wiring and the hull. The reading will not be true, as among other factors it will vary according to whether the meter is opposing or reinforcing the galvanic potential, but it will give a good comparative indication if the same meter is used all the time. With a Fluke series 80 meter, for example, the higher of the two readings should be at least in the kilo-ohm range. Low readings will not necessarily affect the functioning of the system, but are indicative of breakdown of circuit integrity and an inspection should be made of the anode mounting sleeves, junction boxes and cable runs. An infinity reading is equally suspicious, indicating lack of continuity (the alarm light should have come on). As well as an open circuit, a dead ground will cause the red alarm light on the control module to go on. See Section 6 Trouble-shooting. 7.3.3 Leak Check Slacken the glands and screw back the safety caps from the sleeves and check for leaks. If there is a very small seepage, the wet side spacer may swell and stop the leak in a few hours; otherwise the anode nuts must be tightened. When satisfied there are no leaks, make sure the safety caps and gland nuts are fully tightened. 7.3.4 Function Check Check the power supply voltage and make sure the correct voltage is selected in the panel.

After reconnecting the wires to the terminal block, switch on the power and make sure each anode control is responding throughout its range (normally zero to 2 amps). Measure the output voltage for each anode with current set at a given value, say 1.0 amp. Finally, adjust current to the “in port” values.

Check that any peripheral sensors/switches and the corresponding current reduction relays in the panel are operating properly.

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7.3.5 Wiring Verification First verify that the wires connected to the earth return terminals are all showing zero resistance to the hull (except in the case of dedicated cathodes, when it should be infinity). Then check that the positive wires are connected to the terminal block in the proper sequence. A simple way to do this is to switch on the system and set the current for each anode in ascending steps of say 0.2 amps. Then by reading the current at each anode using a DC clamp meter on the tail cable, any crossed wires can be quickly located and correctly reconnected at the panel, and any incorrect tags changed.

7.4 Validation In the case of new installations, the warranty comes into effect after a Cathelco technician or authorised technical representative has completed and signed the attached Commissioning Check List. One copy should be left in the manual. Another copy should be faxed or e-mailed to Cathelco. (See page 1 for contact information.