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14063434.02 10/2019 EN/DE
WIKA operating instructions transmitter, models GDT-20, GDHT-20
EN
6. Commissioning, operation
Bit
Description
0
Pressure signal below the lower limit value (< 0 bar)
1
Pressure signal above the upper limit value (< 16 bar)
2
Pressure sensor failure
3
Temperature signal below the lower limit value (< -40 °C)
4
Temperature signal above the upper limit value (< 80 °C)
5
Communication error pressure/ temperature sensor
6
Pressure density below the lower limit value (liquefaction of SF
6
gas)
7
Gas density above the upper limit value (> 80 g/l)
8
Failure of the humidity sensor (only model GDHT-20)
9
Communication error of humidity sensor (only model GDHT-20)
10
Re-occurring Modbus
®
communication error
Example: 0x0082
Bit 1 and 7 are set. The upper limit values for pressure and gas density are exceeded.
Software reset
Writing 0x0001 in register 202 causes a software reset. After this process all changed
parameters take effect (e.g. change of address).
Reset to factory settings
Writing 0x0001 in register 203 causes the transmitter to be reset to its factory settings and
a software reset is carried out. After this process, all writable registers are reset to the initial
setting.
Start heating process (only model GDHT-20)
Writing 0x0001 in register 204 causes the humidity sensor to manually bake out. Model
GDHT-20 automatically heats in the interval of 30 minutes after completion of the last heating
process. For shorter intervals, the register has to be written manually, the shortest possible
interval is 10 minutes.
Heating frequency
