Electricity + Control May 2016

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Aluminium three-phase 380V and 525V motors for industrial applications
The main benefit of the Bauer range of
aluminium electric motors is that it is far
more lightweight than its cast-iron equiva-
lents due to the aluminium casing and end
shield, Lewis Hiepner, product manager:
electric motors at BI, comments.
“This MS range of aluminium three-
phase 380 V and 525 V motors has been
supplied successfully to the South African
market for the past decade,” Hiepner points
out. A main feature is the multi-mount de-
sign, with the added benefit of being able to
change the feet on-site.This gives the cus-
tomer the option of having the terminal box
on the top or on the left or right hand side,
depending on the specific requirements. In
addition, Bauer motors can be fitted with
an external brake of either an ac or dc type.
The ac brake type is specifically for instant
stopping when the power is switched off.
Applications include bottling plants where
accuracy in the stopping position is critical.
Dc brakes, on the other hand, are slower
in reaction time. This is due to the brake’s
power going through a rectifier in order to
convert ac to dc, with a resultant delay.Typi-
cal applications include overhead cranes,
where stopping accuracy is not as critical.
All Bauer motors conform to the relevant
IEC standards, as well as being designed
for S1 duty.This means that the motors can
run continuously for 24 hours under normal
load conditions. Another feature is the Class
F insulation, with a ‘B’ temperature rise
(80°C plus a maximum ambient tempera-
ture of 40°C, giving a total of 120°C). The
manufacturing process use a vacuum pres-
sure impregnation system in the insulation.
The motors are also IP55 weather-proof,
meaning that they can withstand normal
weather conditions, provided that the cable
termination to the terminal box is carried
out correctly.The Bauer range is also water,
dust and even vermin proof.
Enquiries: Gugulethu Nkutha.
Tel. +27 (0) 11 899 0000 or email
ROUND UP DRIVES, MOTORS + SWITCHGEAR
Drives for Masama wellfields
Rockwell Automation recently supplied medium
voltage drives and soft starter motors for Masama
wellfields – located about 80 km northeast of
Gaborone in Botswana. The hardware was in-
stalled in February 2015 and commissioned in
June, with the wellfields commencing operation
in September 2015.The completion of theMasama
wellfieldsmeans an additional 20Ml/day will sup-
plement the existing 60 Ml/day supply of water
that is delivered through the North South Carrier 1
pipeline. It represents a significant milestone in the
country’s ability to attain long-termwater security.
The RockwellAutomation scope of the project was
mainly as product vendor, and related equipment
design and commissioning. The company sup-
plied two PowerFlex 6000MV ac drives (1 150 kW,
6,6 kV) that will automate the pump system that
transfers water from holding tanks to the North
South Carrier 1 pipeline. Ducting for the drives
was engineered-to-order tomaximise airflowover
the drives to deal effectively with the heat. Allen-
Bradley SMC Flex Soft Starterswere also supplied,
one for each of the 32 boreholes.The soft starters
will play an integral role both in providing motor
protection and in optimising the energy consump-
tion of the wellfields. Rockwell Automation has
been involved in previous phases of the 360-km
North South Carrier pipeline.The PowerFlex 6000
supplements the Rockwell Automation MV drive
range, providing a cost-effective, fit-for-purpose
drive for new and retrofit centrifugal fan and
pump applications rated
up to 10 kV.
Enquiries: Pieter Briel.
Tel. +27 (0) 14 533 4475
or email