PARALLELING
There are no provisions on the CV
DIODE OPTION (Factory installed only)
The CV
METER OPTION
Factory installed Ammeter and Voltmeter
Machine & Circuit Protection (Thermal Protection Light)
The power source is thermostatically protected with proximity thermostats against overload or insufficient cooling. One thermostat is located on the nose of the center bottom primary coil and a second thermostat is attached to the lead connecting the secondaries. Both thermostats are connected in a series with the 2- 4 circuit. If the machine is overloaded, the primary thermostat will open, the output will be zero, and the thermal protection light will be on; the fan will continue to run. The secondary thermostat will open either with an excessive overload or insufficient cooling. The out- put will be zero and the protection light will be on; the fan will continue to run. When the thermostats reset the protection light will be off.
The power source is also protected against overloads on the SCR bridge assembly through an electronic protection circuit. This circuit senses an overload on the power source and limits the output to 550 amps by phasing back the SCR’s.
Protection is provided to protect the circuitry from accidental grounds. If the customer accidentally “grounds” 75, 76, or 77 to the positive output lead, the output will be reduced to a low value, thus preventing any damage to the machine. If the ground occurs between 75, 76, 77 and the negative output lead, one of the PC board
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