THROTTLES AND PRESSURE CONTROL Flashcards
Pages 31-33
Pressure Governor
The pressure governor consists of only two major parts:
the control box (located on the pump panel) and pressure sensor (installed within the discharge manifold).
Pressure Governor
When the pump is engaged the cab throttle controls (accelerator pedal and high idle switch) are _____.
disabled
Types of Governors and Mode of Operation
JFRD utilizes two types of pressure governors:
- Pump Boss 100
* Pump Boss 200
Types of Governors and Modes of Operation
Each pressure governor has two modes of operation:
PSI and RPM
PSI Mode
Any changes to the discharge pressure will be compensated by the governor through a change in:
RPM
PSI Mode
What affects discharge pressure once the PDP is set?
The most common disruption to PDP is the opening and closing of nozzles.
PSI Mode
The engineer must select PSI mode for the following fireground operations:
- Pumping handlines
- Pumping ladder pipes or ground monitors
- Supplying a sprinkler or standpipe systemp
RPM Mode
Engineers must select RPM mode for the following fireground operations:
- Drafting
- Relay pumping
- Charging 5” hose
- PSI mode malfunction
- pumping operations that exceed 300 PSI
RPM Mode
During a drafting operation, the pump may initially be empty. When there is no water in the pump the ____ ____ will not allow the governor to operate in ____ ____.
In ______ the pressure sensor is disabled, allowing the engineer to increase _____ in order to draft.
Once a draft is established you may choose to change to ______.
Pressure sensor
PSI MODE
RPM MODE
RPM
PSI MODE
Governor Operation
With each governor type the following steps must be accomplished in the order listed to ensure proper operation.
- Engage the pump
- Open the TANK TO PUMP valve
- Open the appropriate discharge valve
- Operate the governor
RPM Mode
When relay pumping only the attack engine needs to operate in _____.
PSI MODE
RPM Mode
When opening the LDH discharge valve the PDP may drop suddenly. The pressure sensor will detect this pressure drop and signal the motor to increase ____.
This may result in a pressure spike on other hose lines, possibly to unsafe levels.
Change to ______ before charging 5” hose when using other lines.
RPM
RPM MODE
To operate the Pump Boss Governor:
Once the pump is engaged the Pump Boss governor is on and defaults to ________. It is ready to pump.
The digital readout will indicate the ____.
Changing modes is accomplished by pressing and holding the ______ button or ___ / ___ button for __ ______. The indicator will display the mode selected.
- PSI MODE
- PDP
- MODE
- PSI/RPM
- 3 seconds
Presets
Each pressure governor has a PRESET button and both an RPM and PSI preset are programmed by ____.
The engine PSI preset is -
____ PSI and tanker PSI preset is ____ PSI. The RPM preset for both engines and tankers is _____ .Using the PRESET button is optional.
- TSF
- 110 PSI
- 50 PSI
- 1100 RPM
Tips for Pressure Governor Operation
• Operate two-stage pumps routinely with the transfer valve in _______.
This will result in more efficient operation of the pressure governor and is not harmful to the pump or motor. The discharge pressure at idle will be ___-___ PSI
- VOLUME
* 30-40 PSI
Tips for Pressure Governor Operation
If your water supply runs low the governor will attempt to maintain ____ by increasing ____.
If the pump cannot maintain at least ___ ___ ___, the governor will return the ____ to idle. This is a safeguard to prevent ______.
- PDP
- RPM
- 30 PSI PDP
- RPM
- cavitation
Tips for Pressure Governor Operation
• Flow from the booster tank is limited to ____ - ____ GPM on all JFRD engines.
If you attempt to exceed this amount the digital readout may indicate LO ______ or LO ______ and the governor will return ____ to idle.
If you need to supply the deck gun from the booster tank, use the fog nozzle at ____ GPM or a _____” or _____” tip.
- 700-800 GPM
- SUPPLY or PRESSURE
- RPM
- 500 GPM
- 1–1/4” or 1-3/8”
Tips for Pressure Governor Operation
• When residual pressure gets low (____ __ ___), the governor may sense a supply problem and return RPM to idle. If additional volume is not available and you can safely operate at this residual pressure, change to RPM MODE and continue pumping.
• Below 10 PSI
PSI Mode
Pumping operations that exceed ____ PSI will require the engineer to change to ___ mode. The pressure sensor is disabled above ____ PSI
300 PSI
RPM
300 PSI
RPM Mode
Selecting the ___ ___ disables the pressure sensor, and the governor will maintain the set RPM only
RPM MODE
Presets
The pressure governor can also serve as a high idle control in ____ ____ with the pump _____.
RPM MODE
disengaged
Tips for Pressure Governor Operation
No water hammer can occur from a ___ change
MODE
