Sparks Electrical News August 2017

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SPARKS
ELECTRICAL NEWS AUGUST 2017
MOTOR CONTROL CENTRES AND MOTOR PROTECTION 15
SHAW CONTROLS, a Zest WEG Group company,
reports the successful completion of its contract to
supply a containerised electrical solution to a gold
mine in West Africa.
Kirk Moss, medium voltage manager at Shaw
Controls, says the containerised solution will supply
power to drive a mill on this new mine.
“Containerised electrical solutions are becoming
increasingly popular as these allow for speed of
installation and are a particularly cost effective
option for mine and plants operating in Africa,”
Moss says.
The custom engineered sub-station comprises a
medium voltage (MV) WEG Variable Speed Drive
(VSD) and a dry type phase shift transformer
driving a 2 000 kW, 6 pole, 6,6 kV squirrel cage
WEG electric motor. The VSD is housed in the
container while the oil cooled transformer is housed
outside of it to facilitate heat dissipation.
Moss says that ShawControls has an established
reputation for engineering and manufacturing
quality bespoke containerised solutions at its
Johannesburg facility. The extensive facility of over
12 000 m 2 is manned by a team of skilled technical
personnel and having the whole construction take
place in one facility makes it easier for customers
to do all quality and functional checks in one place.
This solution underwent testing at Shaw Controls
prior to being dispatched to site.
“What is particularly interesting about the
solution provided is that it has been specifically
engineered for this particular application and
utilises specialised software for frozen charge
protection,” says Moss.
The software, which interfaces with the VSD,
allows the objective detection of a frozen charge
condition by making use of torque measurements
already being monitored by the VSD.
“With the addition of an encoder fitted to the
electricmotor,we are now able tomonitor mill angle.
And with the torque and angle measurements it is
possible to detect if cascading has occurred within
the mill,” he explains.
Another innovative feature of this solution is
the supply of a human machine interface (HMI) in
the form of an interactive touch screen which has
been configured to allow different levels of access.
This has been done in a user-friendly manner to
ensure ease of use and also allow simple access
to relevant data.
Moss says that the ability to extract the most
relevant data and provide this in an intuitive
and simplified format allows both operational
and service personnel to monitor the requisite
parameters.
This project made use of a WEG MVW01 VSD
with 6,6 kV output. The input solution makes use of
a 36 pulse rectifier and corresponding phase shift
transformer. Moss explains that this combination
was selected as the best option to minimise
harmonics.
The WEG MVW01 VSD range is available in
3.3 kV and 6.6 kV versions. This is a neutral point
clamped (NPC) topology and makes use of 6,5 kV
IGBTs. These VSDs are engineered with few
components translating into high efficiencies and
optimal reliability.
Also available is the WEG MVW3000 which is
available in 3.3 kV and 6,6 kV, and more recently
in an 11 kV version. This is a cascaded H-bridge
(CHB) topology which makes use of low voltage
IGBTs. This has low voltage power cells with built-in
redundancy (optional) which allows a faulty power
cell to be automatically bypassed with a loss of
performance.
Shaw Controls’ product line includes MV
switchgear and LV withdrawable MCCs – locally
manufactured products that are independently
certified in accordance with the IEC 62271-200
and IEC 61439-1/2 standards. According to IEC
specifications, LV covers applications up to 690 V,
while the MV range is from 1 kV up to 52 kV. All
products carry ISO 9001 accreditation from
Bureau Veritas.
Enquiries: +27 (0)11 723 6000
SHAW CONTROLS DELIVERS CONTAINERISED SOLUTION TO DRIVE MILL
The custom engineered sub-station supplied by Shaw
Controls to a mine in Mali.
SPECTRA* SERIES
8000 LINE
DOUBLE DOOR ENCLOSURE RANGE WITH UPGRADED
PROTECTION DEGREE
MOTOR PROTECTIVE CIRCUIT BREAKERS
Motor control centres provide a conveni-
ent, centralised means of protecting and
controlling all of a facility’s motor loads. In
many facilities today, these motor loads often are
precision HVAC systems responsible for cooling
sensitive electronic equipment - servers, routers,
switches, PCs, etc. Any power outage or fault event
could damage this equipment and ultimately bring
all operations to a halt-resulting in financial losses.
Since 1940, GE Motor control centres have been
designed and manufactured with demanding appli-
cations in mind. Built using Six Sigma quality guide-
lines, GE MCCs offer application flexibility while
adhering to stringent industry standards.
These rugged steel-enclosed motor control cen-
tres can be outfitted with an incredible number of
electrical devices - including all of the following:
• Solid state reduced voltage starters
• AC adjustable speed drives
• Meters
• PLCs
• Control relays
• TVSS devices
• Lighting panelboards
• Distribution panelboards
• Distribution transformers
• GE power management control systems
• Equipment ground fault protection
• Spectra RMS circuit breakers
Enquiries:
UDP wall mounted enclosures in fibre-glass reinforced polyester are an affordable
alternative to stainless steel cabinets for installations in challenging conditions.
Eldon has replaced its entire UDP range of double door enclosures with
upgraded units offering an increased protection degree. Every upgrade
developed aims to help customers stay ahead in a dynamic industrial market.
While the previous UDP double door wall mounted enclosure complied with
IP54, the new version complies with IP65, enabling users to install the cabinets
in even more demanding conditions.
Designed for environments such as public utilities, oil refineries, the marine
industry, photovoltaic energy, and the petrochemical industry, UDP double
door polyester enclosures provide customers with an accessible and efficient
alternative to stainless steel enclosures.
UDP wall mounted enclosures have double insulation to offer users
maximum safety. Different modular enclosures can be combined to achieve
larger configurations.
Customer advantages:
• Increased protection degree, now IP65.
• Suitable for demanding environments.
• Accessible and efficient alternative to stainless steel enclosures.
• Double insulation for maximum user safety.
Please note that there is also a change in the part code. The N has been
removed, thus UDP125100N becomes UDP125100.
Enquiries: +27 (0)11 383 8300
PKE motor-protective circuit-breakers
with electronic wide-range overload
protection offer an interesting alternative
to the bimetal solution for motor currents
up to 65 A. PKE motor-protective circuit-
breakers complement the PKZ device
family.
Features:
• Wide adjustment ranges
• Low heat losses
• Tripping classes greater than Class 10
• Precise and extremely long-time sta-
ble tripping characteristic curves
The benefits of the PKE can be imple-
mented in the motor-protective circuit-
breaker even more efficiently by the
modular design.
The PKE has versatile, approved
accessories available from the PKZM0
system for safe and rational control
panel construction. An interface to
SmartWire-DT also incorporates the
option for integration into the world of
automation.
• Reduction of the number of variants
with its wide adjustment ranges:
simplifies product selection, reduces
inventory and transport-related costs.
• Short-circuit proof up to 100 kA
(400 V) up to 32 A 50 kA (400 V) to
65 A: short-circuit calculations and
prefusing are unnecessary.
• Plug-in trip blocks up to 65 A:
enhance service-friendliness.
• Accessories from PKZM0: minimise
design engineering requirements and
provides flexibility.
• Incorporation into the system
SmartWire-DT: increases the levels of
system availability by the transfer of
process-relevant data.
SmartWire-DT
Using the system SmartWire-DT, the
measurement and status data of the
PKE can be sent directly to the control for
further processing, or directly to an HMI for
visualisation of the motor output circuit data.
The integration of the PKE into the system
SmartWire-DT can be undertaken both for
the individual PKE as well as for the PKE
motor starter combinations MSC-DEA.
Enquiries:
JB Switchgear Solutions was recently awarded a contract by DRA
Global for the design, manufacture and supply of containerised
motor control centres destined for an upgrade project at Rosh
Pinah Zinc in Namibia.
The multi-million Rand contract includes JB Switchgear’s
specially-developed and compact ‘Eagle’ series container panel
which allows two rows of motor control on opposite sides of the
container whilst still maintaining the minimum measurement of
1.2 m (as specified in the Mines Health and Safety Act) between
the opposing fronts of the motor control centres. The design’s
advantages include space saving, cost savings, and the benefit
of full functional testing before the container substation is
dispatched to site. Busbars are easily accessible for installation,
maintenance and subsequent additions and/or modifications.
JB Switchgear’s ‘Eagle’ series carries a comprehensive type
test certification and has proven to be reliable, robust and user-
friendly. More than 31 000 tiers of this design have been installed
in various countries around the globe. The mining sector into
Africa has proven to be a very successful deployment focus for
containerised substations and is expected to grow even further
in the future. In this particular case, there are a large number of
direct-on-line starters and variable speed drives ranging from
0.1 kW to 90 kW.
Enquiries: +27 (0)11 027 5804
SWITCHGEAR
FOR ROSH PINAH