EN
WIKA operating instructions model TR57-M
14222243.02 08/2022 EN/DE
17
Alternatively for North America
The connection can be made in line with “Class 2 Circuits” or “Class 2
Power Units” in accordance with CEC (Canadian Electrical Code) or
NEC (National Electrical Code).
Load diagram
The permissible load R
A
depends on the loop supply voltage.
R
A
≤ (U
B
- 10 V) / 23 mA with R
A
in Ω and U
B
in V
5.3 Behaviour of the electrical output signal
■
Internal instrument error
If an internal instrument error occurs, the error signalling drives
upscale to approx. 22 mA.
■
Medium temperature outside the span
If the medium temperature exceeds that configured within the
transmitter, the transmitter will operate in a linear fashion within the
following limits: 3.7 mA (MRS); 22 mA (MRE).
870
609
Load R
A
in
Ω
Voltage U
B
in V
0
10
24 30
5. Commissioning, operation