BA 3527161/02 EN
9
4.5 Analog output Pt100 Ohm resistance signal
(see also chapter 8.5 for installation examples)
This analogue output is an optional feature to the
MESSKO
®
BeTech Oil and Winding Temperature
Indicators. The simulated Pt100 Ohm resistance output
is linear and proportional to the indicated temperature
on the instrument dial. For typical resistance values -
please see graph and table.
The output can be used for several purposes such as
connection to a computer, to a SCADA system or for
remote monitoring. This output is provided with a 3-wire
connection as standard, to facilitate compensation for
wire resistance etc. Often the output is connected to the
Signal Transducer Pt-MU for transmission over longer
distances.
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
8.5).
A separate shielded cable is recommended for the
wiring to this analogue output. This includes all the
terminals 61, 62 and 63. No other signals should be
wired through the same cable and make sure the shield
is connected to ground on one side only.
Temperature [° C]
Resistance Value [Ohm]
0
100.00
25
109.73
50
119.40
100
138.50
150
157.31
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.