Multiquip SDW225SS - Manual (Page 15)

SDW-225SS WELDER/GENERATOR — OPERATION & PARTS MANUAL — REV. #2 (10/07/05) — PAGE 15
SDW-225SS — GENERAL INFORMATION
SDW-225SS FAMILIARIZATION
Generator
The MQ Power Model SGW-250SS welder/generator can
provide 200 amps of welding current when in the CV/DC
mode and 225 amps of welding current when in the CC/DC
mode. When used as a generator it can provide a maximum
of 6,000 watts of AC power.
Control Panel
The control panel is provided with the following:
z One GFCI 120 volt receptacle, 20 amp (single-phase)
z One 120 volt receptacle, 30 amp (single-phase)
z One 120/240 volt receptacle, 30 amp (single-phase)
z Main Circuit Breaker 240V @25 Amps
z Circuit Protector Breaker (GFCI) 120V @20 Amps
z Idle Control Switch
z Starter Switch
z Warning Lamp Unit
z Hour Meter
z Ground Terminal
z DC (Welding) Output Terminal
Engine Protection System
Engine protection fail safe features are provided in the event
of low oil pressure, high coolant temperature and failure of
the battery to charge. If any of the above conditions occur
while operating the generator it will cause a complete unit
shut down.
Battery Charge Alarm
This unit is equipped with a protective device that signals
an alarm and automatically stops the engine when the battery
cannot be charged by the alternator.
Water Temperature Alarm
This unit is equipped with an apparatus that signals an alarm
and automatically stops the engine when the cooling water
temperature becomes abnormally high. This apparatus will
not function properly if the machine is operated with less
than the proper amount of coolant.
Oil Pressure Warning Alarm
In the event of low oil pressure (engine), this welder/
generator is equipped with an engine protection fail safe
system. If low oil pressure is detected while operating the
welder/generator, the engine protection system will shut down
the engine.
If this condition (low oil pressure) should occur, please refer
to the engine troubleshooting table in this manual.
Welder Protection System
In the event of an overload, this welder/generator is equipped
with a welder protection system. If an overload is detected
while operating the welder/generator, the welder protection
system will shut down the engine.
Open Delta Excitation System
The SDW-225SS generator is equipped with the state of the
art "
Open-Delta" excitation system. The open delta system
consist of an electrically independent winding wound among
stationary windings of the AC output section.
There are four connections of the open delta A, B, C and D.
During steady state loads, the power from the voltage
regulator is supplied from the parallel connections of A to B,
A to D, and C to D. These three phases of the voltage input
to the voltage regulator are then rectified and are the
excitation current for the exciter section.
When a heavy load, such as a motor starting or a short
circuit occurs, the automatic voltage regulator (AVR)
switches the configuration of the open delta to the series
connection of B to C. This has the effect of adding the
voltages of each phase to provide higher excitation to the
exciter section and thus better voltage response during the
application of heavy loads.
The connections of the AVR to the AC output windings are
for sensing only. No power is required from these windings.
The open-delta design provides virtually unlimited excitation
current, offering maximum motor starting capabilities. The
excitation does not have a "
fixed ceiling" and responds
according the demands of the required load.
Engine
The SDW-225SS is powered by a 4-cycle KUBOTA diesel
engine. This engine is designed to meet every performance
requirement for generator. Refer to Table 1 for engine
specifications.
In keeping with Multiquip's policy of constantly improving
its products, the specifications quoted herein are subject to
change without prior notice.
Figures 2 and 3 show the basic controls and indicators for
the SDW-225SS welder/generator.