Current Meter MaintenanceModel OSS-B1

‘Hydrographic Basics’ Training

Course No. 27743

Section 1Prior To Discharge Measurements

Prior To Discharge Measurements

• Remove fan assembly from carry case

• Turn fan carrier anti-clockwise

Anti-Clockwise

Prior To Discharge Measurements

• Separate fan carrier from shaft assembly (keep away from contact with any dirt particles)

• Hold the fan upright and ‘fill’ with approved HS current meter oil

Use Lint Free Tissue

Prior To Discharge Measurements

• Replace axle and fan carrier, excess oil will be forced up through the capillary gap around the axle, ensure fan carrier is tightened

• Wipe the excess oil of

the meter using lint free paper towel

Clockwise

Prior To Discharge Measurements

• Do not forget to close the oil bottle straight after usage to avoid contamination of the oil

• Slide the fan assembly into the body and use the stubby screwdriver to tighten the retaining screw to lock the fan assembly in place

Prior To Discharge Measurements

• Prior to spin test hold the current meter in the horizontal position and spin by hand for approx. one minute to get rid of the hydraulic pressure

• Spin test the meter against time to test the performance of the shaft and bearings

Prior To Discharge Measurements

• Spin test results are dependent on the fan type

• Connect your current meter to the counter using the lead provided (this will test that the lead, reed switch and counter are working prior to use)

• If the current meter fails the spin test, disassemble and clean all components again.

• If the current meter continues to fail the test, replace bearings

OSS-B1 Spin Test

Fan No. Minimum Time (secs)

1 90

A 110

2 90

4 90

Section 2During and After Discharge

Measurements

During and after Discharge Measurements

After every discharge measurement, (or one hour of use), the current

meter should be cleaned and refilled with oil, if continuing a discharge

measurement.

During and after Discharge Measurements

• Undo the cleaning jar cap and ‘¾ fill’ with white spirit

• Remove fan assembly from meter body by undoing the retaining screw and separate the body from the fan

Cleaning Jar

During and after Discharge Measurements

• Remove fan carrier and shaft assembly (do not place in contact with dirt particles)

• Empty the old oil in a recycling container and dispose (do NOT re-use)

During and after Discharge Measurements

• Put the shaft and bearing assembly into the cleaning jar.

• Agitate the jar • Fill up the fan with white

spirit, place your thumb over the hole and shake vigorously for a few seconds.

• Current meter body should be wiped clean with white spirit (there is no need to immerse)

During and after Discharge Measurements

• Blow dry the shaft assembly, fan carrier and fan.

• Re-assemble the fan, coat bearings with a small amount of oil if discharge measurement is complete

During and after Discharge Measurements

• Wipe box clean and return the fan assembly to the case

• If continuing a discharge measurement, refill the fan with oil

During and after Discharge Measurements

• Spin test the current meter against time as shown in section 1

• After the spin test is performed connect your current meter to the counter using the lead, to test the lead, reed switch and counter.

Section 3Office Cleaning

Office Cleaning

Office cleaning should be performed on a monthly basis or whenever the

meter is dirty

Office Cleaning

• Separate fan carrier from shaft assembly

• Current meter body should be wiped clean with soapy water (there is no need to immerse)

Anti-Clockwise

Office Cleaning

• Separate fan carrier (1) from shaft assembly (2)

1 2

Office Cleaning

Remove Nut Remove Bearing

Office Cleaning

Remove Outer Spacer

Remove Inner Spacer

Office Cleaning

Remove Bearing Fan assembly fully dismantled ready to clean

Office Cleaning

Place items in sink, filled with hot soapy water, soak for at least 5 minutes

Clean items with a bottlebrush cleaner

Office Cleaning

Cleaning Fan Cleaning Fan Carrier

Office Cleaning

Cleaning outer spacer

Rinse full assembly with tap water

Office Cleaning

• Place full assembly on lint free tissue

• Ready to dry and re-assemble

• Rinse all items in white spirit prior to re-assembly

Office Cleaning

Dry Fan Carrier Dry Fan

Office Cleaning

Dry Outer Spacer Dry Inner Spacer

Office Cleaning

Blow Dry Bearing & Nut

Office Cleaning

Start Shaft Assembly, Bearing First

Assemble Inner Spacer

Office Cleaning

Assemble Outer Spacer

Assemble Bearing

Office Cleaning

Assemble axle nut Dip shaft assembly in white spirit to lubricate

bearings

Office Cleaning

Blow Excess White Spirit

Assemble Axle With Fan Carrier

Office Cleaning

• Re-assemble fan and place in carry case Clockwise

Section 4Calibration

CalibrationAS 3778 ‘Measurement of water flow in open channels, Part 6.1, Section 7.6 ‘Recalibration’ states:      

“Meters shall be recalibrated whenever their performance is suspect. In practice, for

individually rated meters, recalibration is sometimes carried out at yearly intervals or after

300 h of use, whichever is the shorter.”

Questions?