| Tweet |
Custom Search
|
|
|
||
 TM 9-2320-279-10-3
Principles of Operation (Cont)
1-55. PRESSURE GOVERNOR.
The pressure governor is designed to maintain a selected water pump
pressure or water pump engine speed setting. When the water pump engine
is powered up, the water pump engine will remain at idle until the MODE
switch is pressed to select the desired operating mode, RPM mode, or
Pressure mode.
When the pressure governor is in RPM mode, the message center will display
THROTTLE and the green RPM LED will be illuminated. Water pump
engine speed is controlled by the INCrease and DECrease switches, the
message center will display INCREASE or DECREASE as appropriate when
these switches are depressed. The water pump engine will maintain an RPM
appropriate for the throttle signal being sent. If, while operating in RPM
mode, the pressure increases more than 50 psi (345 kPa) from the pressure
logged at the last switch pressed, the pressure governor will limit the
pressure increase to no more than a 50 psi (345 kPa) difference. The pressure
governor may reduce water pump engine RPM to insure pressure difference.
PSI LIMIT will be displayed in the message center. The pressure governor
will not attempt to regulate pressure in this mode, only limit the pressure
difference to 50 psi (345 kPa) from the pressure present when the last switch
was pressed.
When the pressure governor is operating in the pressure mode, the message
center will display PRESSURE and the amber PRESSURE LED will
illuminate. Water pump pressure is set by using the INCrease and DECrease
switches. The pressure governor will attempt to maintain the last pressure
achieved with these switches. The message center will display INCREASE or
DECREASE as appropriate. The pressure governor maintains water pump
pressure by controlling water pump engine RPM in response to a signal from
the pressure transducers. When controlling in this manner, the message
center will display CTRL DEC or CTRL INC.
Pressing PRESET switch in either mode will control the water pump engine
to attain the preset RPM or water pump pressure programmed in the
pressure governor memory. If there is more than 10 psi (69 kPa) pressure on
the water pump, the RPM preset is disabled and the message center will
display DISABLED.
|
||
|
||
