Class1 107490 - UNI-Governor 107396 107269 software v 6 00 User Manual

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C:\manuals\Uni-Gov-V6-107490

Governor overshoots the PRESET PSI and then oscillates with increasingly wider swings

This can be caused by GAIN being set too high or SENSitivity set too low. In a few cases, the PRESET

is just set too high. PRESET is intended to allow very fast initial response to get up and pumping and a

normal setting would be around 125 PSI. Once the apparatus is pumping water, the pressure setpoint

should be manually invoked with the INC or DEC switches. A two stage pump in pressure mode and a

PRESET PSI of 150 PSI or greater could easily result in oscillations.

Check the GAIN and SENS settings. A lower GAIN will have the biggest impact on this condition.

Do not compensate for operating procedures that can create problems by substituting less than opti-

mum governor operation.

Governor does not respond fast enough to a discharge opening or closing (sluggish)

This is normally the result of the GAIN being set too low. Check the GAIN setting and if less than 4,

change it to a 4 and reevaluate operation. In a rare case, it could be caused by the SENS being set to

7 or greater. Check this and bring it back to a 6 or 7 if necessary. Potentially, this could be caused by

torque loading of the engine being excessive and the apparatus does not have enough “muscle” to

adequately control the pump. If after setting the governor parameters to the best values for response, try

a different pump loading scenario to evaluate power-train efficiency.

RPM PRESET, PSI PRESET or both not working

The governor must have 12 VDC on pin 2 to operate in RPM mode and THROTTLE MODE must be

selected.

If the RPM PRESET doesn’t work, then verify that there is an RPM PRESET. Enter the Password:

INC IDLE IDLE INC IDLE INC IDLE INC

This will place the governor in it’s view settings

mode. The parameter settings will be shown RAMP GAIN SENS is the sequence displayed as X

X X.

This will be followed by the Idle CNTS and then the Pressure Preset PXXX and this is followed by the

RPM preset as a CNT value.

The RPM Preset CNT should be higher than the Idle CNT value by at least 15.

The CNT value is the number of steps on the digital potentiometer used by the governor.

low CNTS=low output and high CNTS=high output. Operational CNTS can be viewed using the

Password

INC IDLE IDLE INC IDLE INC IDLE IDLE

The values seen can be used to identify how many counts relate to engine RPM values.

If the governor works in THROTTLE mode, then the RPM PRESET should work. It is most likely that

the RPM PRESET is not set.

To set PRESET values, enter the following Password:

INC IDLE IDLE INC IDLE INC INC IDLE

The Message Center should display PRESET, select a mode with the MODE switch. You must view

the RPM/PRESSURE LED’s to know which mode you are operating in. Use the INC/DEC switches

to attain the RPM or Pressure you want as a PRESET and then press the PRESET switch to store

the value. Select the other MODE if desired, adjust the setpoint and then store that value with the

PRESET switch. You must then press the IDLE switch to save these settings to memory and exit the

PRESET mode.

If the PSI PRESET does not work, it will be most likely because the transducer signal is not changing.

Operate the apparatus with the pump engaged and water available. Enter one of the following two

passwords dependent on which is easier for you to correlate to operating conditions.

INC IDLE IDLE IDLE IDLE IDLE INC IDLE places you in the transducer voltmeter mode. The

voltage should increase with pressure.

INC IDLE IDLE INC IDLE IDLE INC INC places you in the PSI display mode. The pressure dis-

played should be reasonably close to the master discharge Gauge reading. (+- 25 PSI)

If the values appear not to change with pressure then you will have to diagnose the transducer system.
see

Section Three (3)