8 Connection
8.4 Inputs
PIOX S72*
2022-05-15, UMPIOX_S72xV1-9EN
86
8.4.1
Current input
An active (self-powered) or a passive (external powered) current source can be connected to the current inputs of the
transmitter.
Connection of an active current source
For the connection of the input cable to the transmitter see section 8.2.1, Fig. 8.17 and Tab. 8.12.
If the polarity of the current source is inversed, only the sign of the measured current will change.
Connection of a passive current source
For the connection of the input cable to the transmitter see section 8.2.1, Fig. 8.17 and Tab. 8.13.
At full load (20 mA), a voltage of 22.9 V DC is available for the supply of the passive current source.
Important!
The terminals Txa and Txb must not be connected.
Tab. 8.12: Connection of an active current source
input
transmitter
external circuit
remark
internal circuit
connection
current input
max. permanent overcurrent:
100 mA
Important!
The terminals Txa and TxB must not be connected.
Important!
Observe the correct polarity in order to avoid damaging the current source. A permanent short circuit can lead to the
destruction of the current input.
Tab. 8.13: Connection of a passive current source
input
transmitter
external circuit
remark
internal circuit
connection
current input
max. permanent overcurrent:
100 mA
V
R
int
+
-
TxA
TxB
Txb (not connected)
+
-
-
+
V
R
int
+
-
TxA
TxB (not connected)
Txb
+
-
