Custom-Engineered Electrical Equipment
INTEGRATED VARIABLE-FREQUENCY DRIVES (VFDs)
For Underground-Potash and Other Harsh Mine-Duty Applications
Description
Variable-frequency drives have been used in a variety of
industries for years to start motors, optimize load control, and
achieve energy savings. Unfortunately, the mining industry has
not been able to fully realize these benefits as the combination
of the electronics used in VFD’s and the dirty or harsh
environments found in underground and open-pit mining tends
to decrease the drive’s reliability and expected life.
Littelfuse has solved this problem by designing a
low-maintenance modular system that keeps the critical
components of the VFD isolated from the harsh mining conditions,
yet meets the thermal cooling requirements of the VFD.
One of the benefits of the modular design is the ease in which
the unit can be transported, installed, or replaced. Once the unit
is moved to the operational area of the mine, it can be quickly
connected to the load using cable couplers, programmed, and
put into service, minimizing commissioning and/or downtime.
Patent Pending
The Littelfuse Custom Products engineering team will assist
with your design. All designs are viewed by engineers prior
to quoting.
Low Maintenance, Plug and Play Design
Variable-Frequency Drive
This Littelfuse-designed package has been engineered to
minimize the need for regular maintenance. As a result of the
convenient filter-less design, maintenance is limited to the
simple periodic clearing of dust or debris from the heat sink on
the back section.
Littelfuse modular VFD units incorporate a third-party, high-quality
three-phase variable-frequency drive, selected to give maximum
performance in harsh mining conditions. Cooling is provided
through the use of a flange-mounted heat sink. This is desirable as
it allows the drive’s electronics to be sealed away from the dusty
or harsh environments.
Mine-Duty Enclosure
Enclosures are rugged, mine-duty, and are built to NEMA 4
or NEMA 12 standards. The modular VFD package is designed
for portability with a runner-style or flat-bottom tub and optional
forklift pockets. Trailer-mount units are also available.
Typical construction consists of the following:
Main frame 4” x 2” x 1/4” rectangular tubing
A36 hot-rolled, mild-steel plate, sized as follows:
1/2” flat base plate, 1/4” removable top covers (as applicable),
3/16” outer skin and internal partitions, 10 ga doors
Plated or stainless-steel hinges, latches, and hardware
Sandblasted and covered with a heavy-duty powder coating
Features include:
For use on 600 V loads, up to 350 HP
Wide input supply voltage range
ack-channel VFD cooling removes up to 90% of heat losses
B
from the electrical compartment, which improves reliability
and prolongs life by dramatically reducing temperature rise and
contamination of the electronic components.
Standard white interior and exterior; other colours available
DC fan eliminates the need for the heat sink fan transformer
Quick-connect couplers for incoming and outgoing cables as
per customer specification
IP 54 sealed electronics
Low-voltage compartment doors feature heavy-duty freezer-style
latches. Key-interlocked systems and provisions for padlocking are
provided as required. Doors are formed, gasketed, and hinged.
Where applicable, doors can have wired-glass viewing windows.
Polycarbonate viewing windows are optional.
© 2016 Littelfuse Custom-Engineered Electrical Equipment
Littelfuse.com/CustomProducts
All serviceable parts removable from the front of the drive
Output Filter
Rev: 1-C-051016
Custom-Engineered Electrical Equipment
INTEGRATED VARIABLE-FREQUENCY DRIVES (VFDs)
For Underground-Potash and Other Harsh Mine-Duty Applications
Options
HMI screen provides a graphical interface for control of the
VFD. Additional graphics can be added to display heating
and flow status.Trending screens, drawings, manuals and
maintenance videos are also available with the HMI option.
R
egenerative VFD option returns energy to the grid. When an
electric motor is driven by a VFD, electric power delivered to
the motor is regenerated while the motor decelerates.
Reduced harmonic drives available.
Single Motor Applications (Ventilation,
Pumping, Crushers, Conveyors, etc.)
Built-in variable-frequency drive controls allow programming to
optimize performance and control for variable-speed requirements
such as flow control for pumping and ventilation.
Multiple-Motor Applications (Conveyors,
Pumping, Ventilation, etc.)
For multiple motor applications, such as on conveyors, multiple
units (one master and multiple slaves) can be linked together
for load sharing, load shedding, and speed control.
Wiring
All wiring and buswork is copper. High-voltage wiring is secured
to withstand both thermal and mechanical stress. Wiring to
components is terminated with compression lugs. Wires are
bundled for neatness, reliability, and ease of duct or bundle
maintenance. Control wiring is labeled with heat shrink permanent
markers. A continuous copper grounding bus extends the length
of the enclosure and it is fitted with hardware for customer
connections.
Documentation
Complete documentation is included with each power centre.
Documentation includes three sets of prints and three sets
of manuals containing schematics, layouts, wiring diagrams,
bill of material, recommended spare-parts list, and technical
information on any purchased equipment. The drawings are
available in AutoCAD format.
Testing and Warranty
Littelfuse custom equipment must pass an extensive qualityassurance inspection. Control operation is verified and all
functions are tested. Dielectric and high-voltage tests comply
with applicable standards.
Warranty is 24 months from the date of shipping.
Codes, Standards, & Regulations
Portable modular VFD systems are designed and
manufactured to meet or exceed CSA standards, including
CSA M421 when required.
Ordering Information
3714 Kinnear Place
Saskatoon, SK S7P 0A6
Canada
Tel: +1 306 373 5505
Email: Customproducts@littelfuse.com
Nameplates
Doors, receptacles, assemblies, and major components are labeled
with Lamicoid nameplates. Customer equipment numbers are
added to the exterior of the unit if desired. All compartments are
labeled with appropriate warning labels.
© 2016 Littelfuse Custom-Engineered Electrical Equipment
Littelfuse.com/CustomProducts
Rev: 1-C-051016