2
1.1.3 Pump sensor errors
When the pump sensor signal exceeds the normal range (±1.0 MPa), P. SENSOR
ERROR will appear on the display.
Possible causes:
(1) Pump pressure is too high (1.0 MPa or higher).
This may occur for example when fluid is being pumped by a pump in the
high-pressure gradient system.
(2) Time variation in the pressure sensor.
(3) Malfunction in the pressure sensor or pressure sensor signal circuit.
What to do:
After opening the purge valve, turn the power off and then again. If the error
does not reoccur, the error was probably a result of the pump power being
turned on while the pump was pressurized. If the error reoccurs, time variation
in the pressure sensor or a malfunction in a sensor or signal circuit is the most
likely cause.
If an error arises due to time variation in the pressure sensor, zero the sensor
using the zero adjustment trimmer, then turn the power on again (See Section
3.2). If the problem continues, a malfunction has occurred in the pressure
sensor or pressure sensor signal circuit. If this happens, contact your local
JASCO distributor.
1.2 Errors during operation
Table 1 lists the problems that can be detected by the PU-1580 during operation.
When a problem is detected, a message will appear on the LCD. Press [CLEAR] to
return to the monitor screen.
Table 1.1 Error Messages During Operation
Error Message
Meaning
TROUBLE OVER PRESS!!
TROUBLE UNDER PRESS!!
TROUBLE EXT. STOP IN!!
Operating pressure is too high
Operating pressure is too low
Pump has stopped due to an error
(stop) signal from an external
device
Note: When the setting time of the pump-off timer has elapsed, the PUMP STOP!!
TIMER OFF message will appear and solvent delivery will be terminated.