KROHNE ACM 500 EN - Manual (Page 6)

ACM 500 02/2013 6
2 Electrical connection
Terminals 1(+) and 2(-) are used for supplying a DC voltage of 18...36V. Terminal 2 is connected
to the housing via a protective diode. The maximum power consumption is 180 mA. This value
should be taken into account for the recommended fuse. An active 4...20 mA current output,
galvanically isolated from the supply voltage, is available at each of terminals 3 and 4, and 5 and
6. Terminal pair 3/4 supplies the conductivity signal, terminal pair 5/6 the temperature value. The
negative terminals of current outputs 4 and 6 are connected to each other internally. 24-V control
signals (pnp) can be connected to terminals 7 (R2) and 8 (R1) for external selection of one of the
four adjustable measuring ranges. The ground reference is connected to terminal 2; an open
terminal signifies 0 V.
Meas. Range
R2 R1
1 0 V 0 V
2 0 V 24 V
3 24 V 0 V
4 24 V 24 V
Please note currently valid installation regulations.