Pierce Pumper, Руководство по эксплуатации и техническому обслуживанию

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OPERATION
3-34 / Pierce Pumper
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7. Adjust discharge relief pilot valve.
The discharge relief pilot valve controls the pressure relief setting.
Turn the pilot knob counterclockwise to the left until the amber OPEN indicator light is ON and there is a slight
drop in discharge pressure. Then turn the pilot knob clockwise to the right slowly to the point where the amber
OPEN light is OFF and the green CLOSED light is ON.
If the amber light is ON, the relief valve is open and flow is being bypassed. If more pressure is desired, the relief
valve must be adjusted upward. If the current pressure setting is adequate, reduce the engine speed until the
green light is ON.
3-14.4 Pump Pressure Control With Pressure Governor (Pumping)
In an apparatus equipped with a pressure governor, the governor will regulate the engine speed automatically
to maintain the desired pump pressure. When placed in the PRESSURE CONTROL mode, the system will
monitor pressure, increasing or decreasing the engine speed to maintain the set pressure.
NOTE: For additional information concerning the operation of specific pressure governors, refer to the
following:
• PV-P-TM350, Pierce Pressure Governor Operator’s Guide on CD-ROM and Group 2825-P-
001, Pierce Pressure Governor System (in Service Manual)
• Group 2825-P-003, Pierce Hydraulic Water Pump Pressure Controller (in Service Manual)
• Group 2825-V-001, Class 1 Pressure Governor (in Service Manual)
• Group 2825-V-002, Detroit Diesel Electronic Fire Commander (in Service Manual)
1. Select pressure control mode.
Place pressure governor in the PRESSURE CONTROL mode. Switching methods will vary depending on the
manufacturer of the pressure governor.
2. Adjust desired pressure.
Use the INCREASE or DECREASE controls to change the desired pressure setting.
Pressure hazard. May result in personal injury. Always reduce pressure with engine throttle to ensure
the relief valve is closed before turning the valve OFF.
Apparatus equipped with pressure governors normally do not have pressure relief valves. The
pressure governor performs the function of the relief valve.
Always pump in pressure control mode.
Pumping in throttle (RPM) control mode can cause high pressure and/or pressure spikes. Pressure
spikes can injure or kill.