Stahl 9180, Operating Instruction

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Operating Instuctions English
20 Resistance Isolator Type 9180
7.3 Line fault detection and exceeding measurement range
A line fault is detected, if the resistance reaches the following values:
Type Application Fault signalisation at resistance of
9180/10-77-11
9180/20-77-11 Pt 100
R < 16,5 Ω or R > 393,5 Ω
9180/11-77-11
9180/21-77-11 Pt 1000
R < 165 Ω or R > 3935 Ω
The device indicates the fault by LED “LF”, contact and common line fault detection via
optional pac-bus.
In case that the line fault detection is deactivated and the measurement range is exceeded
as des
cribed above, the LED “LF” is flashing.
7.4 2-wire line balancing
When connecting resistance thermometers in a 2-wire circuit, balancing of the line
impedance must be performed before putting the device in operation:
1. Short-circuit the resistance thermometer directly at the sensor.
2. Use the front-facing DIP switch ADJ1 (channel 1) or ADJ2 (channel 2) to balance the
line impedance:
Within approx. 10 seconds, switch the DIP switch “ADJ” on and off as follows:
OFF - ON
–
OFF
–
ON
–
OFF
3. The green "PWR" LED blinks if the line balancing was successful