HB Products HBLT-A1 Liquid Level Transmitters
Publication 9-86
Section 9
Page 10 of 10
Issue 1 : 10/22
7.
Maintenance
No routine maintenance is required other than periodically checking that
the level indicated corresponds to the liquid level within the vessel.
If the system uses R717 (ammonia) refrigerant, oil may tend to collect at
the bottom of the level column. The HBLT-A1 is less susceptible to oil
logging than other designs of level transmitter, however, if it is suspected
that oil accumulation might be interfering with the correct operation of the
transmitter, drain off the oil using the apparatus and method illustrated
and described in Pumping Down, Recovering Ammonia Refrigerant
Charge in publication 5-20 in Section 5.
8.
Faults and Remedies
Some of the more common fault conditions are given in Table 3.
Fault
Probable Cause
Remedy
No function, green LED not lit.
No power supply or power supply incorrect, faulty
wiring/plug.
Check power supply is available, supply polarity and
voltage is correct. Check wiring continuity and plug
connections.
Level transmitter electronic defective.
Replace electronics.
No 4 to 20 mA output signal, green LED flashes
rapidly.
Faulty wiring/plug
Check supply polarity. Check wiring continuity and
plug connections.
4 to 20 mA output signal does not correspond to the
actual liquid level
Wrong refrigerant selected.
Select correct refrigerant; refer to 6.1.
Level transmitter not calibrated or incorrect
calibration.
Calibrate level transmitter; refer to 6.3. If calibration
has been carried out incorrectly, restore factory
default settings before recalibrating.
4 to 20 mA output signal is low or erratic
Oil accumulation in the standpipe.
Drain off the oil; refer to 7. Maintenance.
After supplying power to the level transmitter, there is
a long delay before the 4 to 20 mA output signal is
recognised and updated
Minimum/maximum calibration has been carried
out many times.
When power is applied to the level transmitter the
LED will flash rapidly as many times as the
transmitter has been calibrated during its lifetime.
The 4 to 20 mA output signal is recognised and
updated as soon as the flashing changes from rapid
to slow flashing.
Table 3 Faults and Remedies
9.
Spare Parts
Obtain spare parts from the address below:
J & E Hall International Telephone: +44 (0) 1332-253400
Hansard Gate,
Fax: +44 (0) 1332-371061
West Meadows,
Email: [email protected]
Derby,
Website: www.jehall.com
DE21 6JN
England
When ordering always quote the J & E Hall International contract number
and the component serial number (if available).
10. Safe Disposal, End-of-life (EOL)
At the end of the level transmitter's working life, it should not be classed
as domestic waste but be disposed of separately by a registered
recycling company according to local and currently valid legislation.
