lifting high, fast and safely
TRANSCRIPT
lifting high – fast and safely Reference Story
Safety and reliability are key issues in vertical access sys-
tems, especially when operating at great heights. RAXTAR
designs and manufactures high quality construction hoists
for passengers and materials, industrial lifts and transport
platforms. Vacon AC drives are needed for motor control.
RAXTAR − based near the city of Eindhoven in the south of
the Netherlands − manufactures vertical access solutions
that are based on decades of experience and meet the high-
est quality and safety standards. Compared to conventional
hoists, RAXTAR’s customers save signifi cantly on mainte-
nance costs thanks to the robustness of the hoists and their
fl exible design based on open standards.
RAXTAR’s passenger and material hoists operate at the heart
of the logistics on construction projects. RAXTAR construc-
tion hoists guarantee the supply of materials and personnel
around the clock, at the right time and in the right place (and
height).
Adjusting the speed according to the load of the hoist
RAXTAR’s hoists and lifts use Vacon AC drives for motor
control. “The choice of Vacon is based on the reliability and
quality of Vacon’s solutions. Reliability and quality are the key
values for our products and solutions,” says Pascal Matheeu-
wsen, CEO of RAXTAR.
The fi rst contact between Vacon and RAXTAR was at the end
of November 2007 when RAXTAR was urgently looking for a
new drives solution for their hoists. Vacon proposed a Vacon
NXS unit (205 A/110 kW) for testing. Dick Kant, Sales Sup-
port Engineer at Vacon Benelux, recalls: “RAXTAR asked us
to conduct joint tests with them to see if the performance of
the Vacon AC drives met their requirements for the passen-
ger hoists. The total weight load of the hoist is about 5,500 kg
(12,125 lbs), and it has a net load of 2,700 kg (5,952 lbs). The
hoist was lifted by two motors, a gearbox in open loop with a
total power of 76 kW and a Vacon NXS drive of 90 kW. After
some slight modifi cations we succeeded in running the hoist
without problems.”
However, RAXTAR had a challenge for Vacon: they wanted the
hoist to run always at the highest possible speed. “Our team
at Vacon Benelux designed a software application that deter-
mines the load of the hoist and adjusts the speed according to
the load, so the hoist runs at the highest possible speed when
needed,” Mr Kant continues.
Major projects from New York City to Milan
One of the biggest challenges and most successful coop-
eration projects between RAXTAR and Vacon is the recon-
struction of one of the world’s most famous buildings, the
One World Trade Center (formerly called Freedom Tower) at
ground zero in New York City, USA. The customer demanded
hoists that could carry 3,200 kg (7,055 lbs) up to 300 m (984 ft).
This required a hoist with three motors and a total power of
110 kW. A total of twelve RAXTAR construction hoists, travel-
ling at a maximum speed of 92 m (302 ft)/min, are equipped
with Vacon NXP drives of 132 kW and provide the logistics for
this remarkable project for 16 hours a day, six days a week.
The 132-kW Vacon NXP drives are provided with Open Loop
Control and an OPT-AF card*.
Vacon Group
Runsorintie 7
65380 Vaasa, Finland
Tel. +358 (0)201 2121
Fax. +358 (0)201 212 205
E-mail [email protected]
www.vacon.com RS
00
01
44
A
At the same time, RAXTAR is providing construction hoists
for one of the largest construction sites at the moment in Eu-
rope, the CityLife project covering an area of 255,000 square
metres (2,744,820 sq ft) in the centre of the former trade fair
area in Milan, Italy. Seven RAXTAR hoists with a payload of
2,700 kg (5,952 lbs) and a travelling speed of 72 m (236 ft)/
min guarantee safe access for people and material to differ-
ent buildings at the site. The customer’s choice of RAXTAR is
based on both the quality and fl exibility of the solutions.
In Mr Matheeuwsen’s view RAXTAR and Vacon have many
things in common: “As well as sharing a common vision on
quality, the relationship between Vacon and RAXTAR is based
on a cultural fi t. Day-to-day co-operation between Vacon and
RAXTAR personnel guarantees the highest level of service,
relating to both the reliability and fl exibility that we need to
provide for our customers globally.”
Hoists feeding energy back to the network
Today, RAXTAR and Vacon have an open partnership where
the expertise of both companies is used to develop new and
innovative world-class solutions for the construction and in-
dustrial markets.
RAXTAR and Vacon are now developing a hoist that will re-
duce energy consumption. When the hoist is going down, it
will supply energy back into the network instead of feeding
it into the brake resistors. For RAXTAR’s customers this will
bring energy savings. The fi rst two hoists were installed on
construction sites in The Netherlands in June 2011. BAM
Group and Dura Vermeer, two leading Dutch construction
companies, were the fi rst to work with this “green” solution.
Modular design of Vacon drives
Since modularity is important for RAXTAR, the top drive unit
can also run conventionally with brake resistors, so the hoist
can be used in every situation. Vacon’s modular design makes
it possible to replace the active front-end unit with brake re-
sistors, so the hoist can also be run on a generator supply.
Frank Kennis, Head of Technology & Innovation at RAXTAR,
says: “In order to competitively develop, design and manu-
facture the kind of solutions RAXTAR offers to the market, we
often need to let go of conventional thinking. RAXTAR mixes
and matches innovative technologies to create solutions that
answer to − or even exceed − our customers’ demands for
safe and reliable vertical access systems. Long-term rela-
tionships, in which each party clearly understands this re-
quirement, are crucial for achieving this goal.”
RAXTAR’s construction hoists at the One World Trade Center building project (formerly called Freedom Tower) in New York City. Each RAXTAR hoist cabin can lift 3,200 kg (7,055 lbs) and travels at a maximum speed of 92 m (302 ft)/min. All RAXTAR’s solutions are either CE marked and certifi ed according to European Norms and Regula-tions or comply with North American Standards. Photos courtesy of RAXTAR.
The Vacon NXP was the perfect fi t for the tower construc-tion project in New York City. The total weight of the hoist loaded is about 7,300 kg (16,094 lbs).
*Thanks to Vacon’s advanced lift software it is possible to control the hoist in Open Loop. The AF card was integrated to improve security and to reduce the number of components.