BA 3527161/02 EN
6
4
Electrical connection
4 Electrical connection
4.1 Connecting the microswitches
To connect the microswitches open the housing via the
four screws of the housingh cover (Fig. 1/2). Remove
the outer sheaths of the connecting cables to a length
of approx. 160 mm and then the insulation of the indi-
vidual conductors to a length of approx. 6 mm. Install
the cable glands provided loosely to the incoming
cables and housing.
Pay close attention to cable gland assembly and
ensure that the seal is properly fitted to avoid any water
ingress. Connect the incoming wiring to the terminal
strip (Appendix, chap. 8.7) in accordance with the con-
nection diagram (Appendix, chapter 8.2 - 8.6).
4.2 Analog output 4 - 20 mA current loop signal
(see also chapter 8.2 for installation examples)
This analogue output is an optional feature to the
MESSKO
®
BeTech Oil and Winding Temperature
Indicators. The output is linear and proportional to the
indicated temperature on the instrument dial, where
4 mA is provided at the lowest value on the dial and
20 mA at the highest value, for instance 4 mA at 0 °C
and 20 mA at 150 °C (see graph).
The output can be used for several purposes such
as connection to a computer, to a SCADA system or
for remote monitoring by Remote Analogue or Digital
Indicators. Because of the high load allowed, the same
output can be used for more than one purpose at the
same time.
Since the output is provided from the indication,
the same temperature is displayed both locally and
remotely - no differences because of settings etc as if
separate transmitters are used.
The electrical wiring is easily connected to the terminal
board inside the OTI or WTI (see appendix, chapter
8.2).
CAUTION
The terminals 61, 62 and 63 must be short-circuited
during insulation test. The test voltage must be rai-
sed gradually. Remove the clamps on the terminal
board once the tests are finished.
WARNING
Electrical voltages, danger to life!
All connecting wiring must be free of voltage before
opening the device.
CAUTION
When closing the housing tighten the srews with a
torque of max. 1 Nm.
Fig. 3