301/303/305/306/307 Flowmeters and Controllers Instruction Manual
EAR99 Technology Subject to Restrictions Contained on the Cover Page
Page 22 of 32
3. Maintenance
This section contains service and calibration information. Some portions of the instrument are delicate,
so please use extreme care when servicing the flow controller.
NOTICE:
It may prove more prudent in the long run to delegate the maintenance of Hastings
flow instruments to Hastings personnel who have the appropriate equipment and training.
Improper adjustments to the flow instruments can result in inaccurate data, poor instrument
function, and may lead to sending the unit back for repair.
CAUTION:
Some parts of the instrument are delicate and other parts are heavy enough to
cause an injury if dropped. Use extreme care when servicing the instrument.
With proper care in installation and use, the flow controller will require little or no maintenance. If
maintenance does become necessary, most of the instrument can be cleaned or repaired in the field.
Some procedures may require recalibration. Do not attempt these procedures unless facilities are
available. Entry into the sensor or tampering with the printed circuit board will void the warranty. Do not
perform repairs on these assemblies while unit is still under warranty.
Troubleshooting
This section includes some of the more common issues that may arise when using a Hastings flow meter
or controller. Symptoms, causes, and recommended actions are grouped with each problem.
Symptom:
Output reads strong indication of flow with no flow present. Zero pot has no effect.
Cause:
Power shorted out.
Action:
Turn power supply off for a few seconds, and then turn it on again. If this is
ineffective, disconnect the power supply from the unit. Check that the power supply
voltages are correct. Incorrect voltages most likely signify a faulty regulator chip
inside the supply. If using a Hastings power supply and the display returns to zero after
the instrument has been disconnected, there may be a short from the unit to ground.
Symptom:
Hastings 300 output continues to indicate flow with no flow present or indicates
±14 volts. Power supply inputs are correct and zero pot has no effect.
Cause:
Faulty IC chip(s) on the main PC board.
Action:
Replace main PC board. (See 3.4)