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THYRISTOR OR SCR LOADING
Solid state electronic control devices which
utilize thyristors or SCR firing circuits (such
as variable frequency induction motor
controls, precision motor speed controls, no-
break powered battery chargers, etc.) can
introduce high frequency harmonics which
adversely affect or destroy the normal
waveform of the generator. This creates
additional heat in the generator stator and
rotor, and can cause overheating. These
devices can and do present problems to non-
utility power generating equipment or any
limited power bus system. The problems that
can occur are not limited to the generator
itself, but can effect the solid state control
device, the equipment it controls, other
associated loads, monitoring devices or a
number of combinations over the entire
system.
MagnaMAX generators can supply power to
thyristor or SCR loads when properly applied.
The standard voltage regulator is PMG
powered and senses 3 phase RMS voltages for
maximum stability against severely distorted
waveforms. SCR type applications such as
cranes, shovels, etc., require special
consideration of the generator insulation
system due to greater dielectric stress and
severe environmental conditions. It is impor-
tant that the control manufacturer, the
generator manufacturer, and the systems
engineer work together to insure the proper
selection of all components. Please refer to
Marathon Electric for application assistance.
OPERATION
PRE-START INSPECTION
Before operating the generator for the first
time, the following checks are recommended.
1. A visual inspection should be made to check
for any loose parts, connections, or foreign
materials
2. Check for clearance in the generator and exciter
air gap. Be sure the generator set turns over freely.
Bar the generator over by hand at least 2
revolutions to be sure there is no interference.
DO NOT APPLY ANY FORCE TO THE
GENERATOR FAN FOR LIFITNG OR
FOR ROTATING THE GENERATOR
ROTOR. DISREGARDING THESE
INSTRUCTIONS MAY CAUSE
PERSONAL INJURY OR EQUIPMENT
3. Check all wiring against the proper connection
diagrams and make sure all connections are
properly insulated. Support and tie leads to keep
them from being damaged by rotating parts or by
chafing on sharp corners.
4. Be sure the equipment is properly grounded.
5. Inspect for any remaining packing materials and
remove any loose debris, building materials, rags,
etc. that could be drawn into the generator.
6. Check fasteners for tightness.
7. Check to be sure no tools or other hardware
have been left inside or near the machine.
8. Install and check to be sure all covers and
guards are in place and secure.
WARNING
RESIDUAL VOLTAGE IS PRESENT AT THE
GENERATOR LEADS AND AT THE
REULATOR PANEL CONNECTIONS EVEN
WITH THE REGULATOR FUSE REMOVED.
CAUTION MUST BE OBSERVED OR
SERIOUS PERSONAL INJURY OR DEATH
CAN RESULT.
21
WARNING
DAMAGE
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