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 vacon@vacon.com

www.vacon.com RS

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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.