BENSHAW M2L 3000, User Manual

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Glossary
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voltage transients on the incoming Medium Voltage power by shunting those transi-
ents to ground.
Thermal Switch Isolation
Receiver Board
A Thermal Switch Isolation Receiver Board is a circuit board with four fiber optic re-
ceivers and four relay outputs. The Converter has a Thermal Switch Isolation Re-
ceiver Board in its Low Voltage Box. The Thermal Switch Isolation Receiver Board is
connected by fiber optic cables to Thermal Switch Isolation Transmitter Boards. The
fiber optic cables between the boards isolate the thermal switches on the Medium
Voltage components from the controls used to monitor them.
Thermal Switch Isolation
Transmitter Board
A Thermal Switch Isolation Transmitter Board is a circuit board that monitors two
thermal switches, and transmits their state over two fiber optic cables to a Thermal
Switch Isolation Receiver Board. The Converter has a Thermal Switch Isolation
Transmitter Board in its Rectifier Section and another in its Transformer Section.
The fiber optic cables between the boards isolate the thermal switches on the Me-
dium Voltage components from the controls used to monitor them.
Concepts
Arm
In an Error! Reference source not found. , Multiple Power Cells are connected in
series with a Pole Filter in the middle to create a phase. One end is connected to the
positive side of the DC bus, the other end is connected to the negative side of the
DC bus, and the middle connection point of the Pole Filter is connected to the
Error!
Reference source not found. ’s output. The cells between the positive side of the
DC bus and the Pole Filter are the Positive Arm of the phase. The cells between the
negative side of the DC bus and the Pole Filter are the Negative Arm of the phase.
ATL
Across-The-Line is when a motor is connected directly to the line. It is not being con-
trolled by the drive.
Control Power
Control Power is used within the drive to power its controls and auxiliary equipment.
It does not provide power to the motor controlled by the drive.
Front End
The Front End portion of a drive converts the incoming AC Line voltage into a DC
voltage, which is then converted back into an AC voltage by the Inverter.
A conventional Front End uses diode bridges to convert AC to DC. It may use a
transformer with multiple phase-shifted outputs, and multiple diode bridges to reduce
the ripple on the generated DC voltage and to reduce the harmonics on the input.
An Active Front End uses power semiconductor switches instead of diode bridges,
doesn’t require a transformer, and can transfer power from the inverter back onto
the line.
Ground Fault
A Ground Fault is an unintended contact between energized conductors is ground. It
results in current flow through the grounding system, equipment, or personnel that
provides a path to ground.