WIKA intelliTHERM TGT70, Operating Instructions Manual

Page: 9 / 60

WIKA operating instructions model TGT70 9
EN
14047194.03 03/2022 EN/DE/FR/ES
3.1 Output signal and permissible load
Voltage output (3-wire): R
A
> 5 kΩ
Current output (2-wire) 4 ... 20 mA:
R
A
≤ (U
SIG
- 10 V) / 0.02 A with R
A
in Ω and U
SIG
in DC V
3.2 Electrical connection
Lateral terminal box, connector M12 or cable outlet
Pin assignment
Output signal U
B+
U
B-
Signal
2-wire (current output) 1 2 -
3-wire (voltage output) 1 2 3
Wire colour (for cable outlet)
U
B+
U
B-
Signal
red black orange
Operate the instrument with shielded cable, and ground the shield on at least one end
of the lead, if the lines are longer than 30 m or laid outside of buildings.
This is an instrument for operation with extra-low voltages, which are separated from the
mains or for voltages higher than AC 50 V or DC 120 V. A connection to SELV circuits
or alternatively to circuits with a protective measure according to IEC 60364-4-41 is
recommended.
For further specifications see WIKA data sheet TV 18.01 and the order documentation.
4. Design and function
4.1 Description
The closed measuring system with liquid filling consists of a temperature sensor, a
capillary and a Bourdon tube. The volume change as a consequence of the heat applied
to the temperature sensor, and thus the pressure change in the closed system, is
transmitted through the capillary to the Bourdon tube and then indicated on the dial by
an angular deflection of the pointer shaft.
Through the combination of a mechanical measuring system and electronic signal
processing, the process temperature can be read securely, even if the power supply is lost.
U
SIG
Permissible range
4 ... 20 mA, 2-wire
3. Specifications / 4. Design and function