GE MS6001B, Maintenance Instructions Manual

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Inspection and Maintenance Procedures Inspection and Maintenance
IMP–2
Vibration Detectors
Monitor the vibration levels during operating. Insure each vibration detector is functional. Vibration lev-
els may be monitored directly on the turbine panel.
Physically check the mounting security of each vibration detector and detector leads.
Refer to the Control Specifications and Control Specifications — Control System Adjustments for com-
plete operational checks.
Liquid Level Indicators
When the tank is drained of liquid, check that the linkages are free from binding and the float is in good
condition. Make sure the high and low level switches are set within the limits specified on the Schematic
Piping Diagram.
Panel Meters
Unless a competent instrument mechanic is available, it is recommended that the instrument be returned
to the manufacturer, or a laboratory, for calibration and for repairs.
In general, instruments should be on “zero” when the unit is shutdown. Whenever possible, corrections
should be made with the “zero” adjustment. If a pointer cannot be zeroed, it is probably bent, or the
“zero” adjuster crank arm is out of the regular slot.
Inspect for sticking, or jerky pointers. The most common causes of erratic operation are dirt on the scale,
pointer touching glass, dirt in a gap of moving element or damping magnet, or damaged bearing. Correct
as necessary.
CONTROL DEVICES
Temperature Switches
Temperature switches are pretested, set, and locked in the factory. If trouble is experienced in the field,
new pretested and set switches should be ordered. Faulty switches should be returned to the GE Compa-
ny for evaluation. These switches should not be tested, adjusted, or reset in the field unless a special Fen-
wal Test Kit, Model 80001-0, is available since the settings require close tolerances. The arrow on the
head of the thermoswitch unit indicates the direction to turn the adjusting screw for increased tempera-
ture setting. One complete turn of the adjusting screw equals approximately 100
°
F (56
°
C).
Thermostats
To check the accuracy of the space heater thermostats in the turbine, accessory and control compart-
ments, compare the setting of the thermostat with the temperature shown on an accurate thermometer.
If there is a discrepancy of more the five degrees, the thermostat should be repaired,or replaced.
Pressure Regulating Valves (VPRs)
Pressure regulating valves are of two types — pressure reducing and backpressure regulated. Except in
a few instances, a line-mounted pressure gauge is available very close to the valve to check and/or set