Endress+Hauser RIA15 - Page 18

Wiring RIA15
18 Endress+Hauser
The HART
®
communication resistance of 230 Ω in the signal line is always necessary in
the case of a low-impedance power supply. It must be installed between the power
supply and the display unit.
Circuit diagram / Description
2-wire sensor with
process display unit and
loop power supply,
without backlighting
Y
I
R
s
DC
1
2
3
LED
- +
A0019567
1 Sensor
2 Power supply
3
HART
®
resistance
2-wire sensor with
process display unit and
loop power supply, with
backlighting
Y
I
R
s
DC
1
2
3
LED
- +
A0019568
1 Sensor
2 Power supply
3
HART
®
resistance
4-wire sensor with
process display unit and
loop power supply,
without backlighting
1
3
Y
I
2
4
LED
- +
A0019570
1
HART
®
resistance
2 Current meter (optional)
3 Sensor
4 Power supply 4-wire device