Magnetic Instrumentation 942B, Инструкция по эксплуатации

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Negative Bias Circuit
The secondary of T2 feeds the power supply for the negative bias circuit. T2’s secondary
is rectified by bridge rectifier D2 and filtered by capacitors C5 and C7. The positive of the
bias supply is referenced to the negative side of the gate drive power supply. Resistor R6
limits the bias current to approximately 0.04 amps. Diode D14 is forward bias by the
negative bias supply limiting the voltage to approximately 0.7 volts in the opposite
polarity to that of the gate drive circuit. This insures that C11 discharges at the end of the
gate drive output signal.
VI. SERVICE AND MAINTENANCE
Service and maintenance of this equipment requires trained personnel.
Care is required for safety of service personnel. High Voltage is exposed
with panels removed. This unit should be operated with the panels
removed ONLY if absolutely required for repair.
A. General Instructions
The Model 942B Magnetizer is a combination of electrical and electronic components.
Procedures consistent with safety and standard practices for each area should be used.
Regular service should be performed to insure proper connection of all terminals.
If water is used for cooling, all water connections should be inspected regularly for leaks
or obstructions. A regular inspection of the drain will prevent component failure due to
overheating.
B. Test Equipment
Portions of the circuitry in this machine are isolated from earth ground. Trouble-shooting
and repair must be carried out by qualified personal using properly rated test equipment.
Failure to do so may result in damage to the Magnetizer and/or test equipment.