USER HANDBOOK 1.2 | ECC DIO / ECC AIO
Berghof Automation GmbH | Harretstrasse 1 | 72800 Eningen | www.berghof.com
250000600_ECC-DIO-AIO_Anwenderhandbuch_EN.docx
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Temperature measurement AI (T)
Fig. 19: Example connection: temperature measurement
Item
Description
1
PT 100 or PT 1000 with 2-wire connection
2
PT 100 or PT 1000 with 3-wire connection
Only use the corresponding AGND for each power input.
Do not connect AGNDs from different channels.
Only use one channel per function: either AI (U) or AI (I).
Do not connect to the common GND. The required connections can already be found on the circuit
board.
Cables to the PT100(0) sensors should be connected as directly as possible (avoid the use of terminals
and terminal blocks).
Only connect PT100(0) sensors to AI (U/T) channels. Each 14-pin plug-in connector has 2 AI (U/T)
channels.
2-wire measurement
Resistance can result in a measurement error, which in the case of long cables with a small cross-section can
be up to 10°. If the temperature of the sensor is known, this deviation can be subtracted by the software
automatically and compensated (alternatively, use 3-wire measurement).
3-wire measurement
The nearest AI (U) connection is used to compensate the resistance in the cable. It can only be used directly
in conjunction with the following AI (U/T) channel.