WIKA TR33 - Handbuch (Seite 20)

GB
14073818.01 01/2014 GB/D
20 WIKA operating instructions model TR33
Do not exceed the following values:
■ Version with 4 ... 20 mA output signal
Power supply and current loop circuit (connections)
Voltage U
i
DC 30 V
Current I
i
120 mA
Effective internal capacitance C
i
6.2 nF
Effective internal inductance L
i
110 µH
Sensor current loop
Power P
o
37.5 mW
Ambient temperature -40 ... +85 °C (-40 ... +185 °F)
The maximum self-heating at the sensor tip is 4 K
■ Version with Pt100 and Pt1000 output signal
Sensor current loop
Voltage U
i
DC 30 V
Current I
i
550 mA
Effective internal capacitance negligibly small
Effective internal inductance negligibly small
Ambient temperature -40 ... +85 °C (-40 ... +185 °F)
6.3 Behaviour of the electrical output signal
■ Sensor break and short-circuit
Sensor break or short-circuit are signalled after positive detection
(after approx. 1 second). If this fault condition has been caused by
a malfunction, then a relevant measurement signal must exist for
approx. 1 second in order to return to measuring mode. From the time
of the error detection up to the fault signal, the last relevant measured
value will be delivered on the current loop.
Therefore, in the event of a “true” sensor break or short-circuit, this
is also signalled permanently. In the event of a “false” sensor break
or short-circuit, the transmitter has the possibility of reverting to
measuring mode.
6. Commissioning, operation