HB Products HBLT-A1 Liquid Level Transmitters
Section 9
Publication 9-86
Issue 1 : 10/22
Page 7 of 10
6.1.
Selecting the Refrigerant
The liquid level transmitter is supplied factory set for use with R717
(ammonia) refrigerant. If this refrigerant is used there is no need to
change this setting. For other refrigerants, or if the transmitter housing
electronics have been replaced, proceeds as follows:
(a) Arrange to measure the 4 to 20 mA output signal.
(b) Disconnect the power supply by unplugging the DIN plug from the
transmitter housing.
(c)
Press the calibration pushbutton and keep it pressed while
restoring the power supply (reinstate the DIN plug). Release the
pushbutton.
NOTE: If the power supply is restored before the
calibration pushbutton is pressed, the signal damping
will be changed; refer to 6.2.
(d) Observe the green LED flashing, at the same time measure the
4 to 20 mA output signal; refer to Table 2.
Green LED Number of Flashes
4 to 20 mA Output Signal
1
Refrigerant
1 flash
5 mA
R717 (ammonia) (factory setting)
2 flashes
6 mA
R22 and R507A
3 flashes
7 mA
R404A
4 flashes
8 mA
R134a
5 flashes
9 mA
R744 (CO
2
)
1
For refrigerants not listed, contact J & E Hall International.
Table 2 Refrigerant Settings
(e) Press and release the pushbutton to step down through the list
until the number of LED flashes and the output signal correspond
to the required refrigerant.
When the output current corresponds to the required
refrigerant, wait 10 seconds until the green LED is constantly
lit (not flashing). This indicates that the required refrigerant
has been selected.
(f)
Leave change of refrigerant mode by disconnecting the power
supply to the transmitter (unplug the DIN plug from the transmitter
housing).
(g) Reinstate the power supply.
6.2.
Signal Damping
The signal damping setting range is 1 to 120 seconds, factory setting 15
seconds. To change the signal damping proceed as follows:
(a) Disconnect the power supply by unplugging the DIN plug from the
transmitter housing. Restore the power supply (reinstate the DIN
plug).
(b) Press and release the calibration pushbutton. Each press and
release increases the signal damping by 1 second from 1 second
up to a maximum of 120 seconds.
For example, to set signal damping to 37 seconds, press
and release the pushbutton 37 times.
(c)
10 seconds after the last press and release, the damping value is
saved to memory and the green LED will start flashing.
If the damping is set too high, repeat the procedure from
step (a).
