Val Controls I 24-AF Series - Communication; Control Loop - AI0 and Transmitter Loop - AO0 (HART)

DHW-UM-004
Val Controls A/S • Sallingsundvej 5 • DK-6715 Esbjerg N • Tel. +45 7547 0600
vc@valcontrols.com • www.valcontrols.com
Revision: 4
4/20
2 Communication
Several communication types are available as options.
2.1 Control loop – AI0 and Transmitter loop – AO0 (HART)
Passive 4-20mA input and passive 4-20mA output. On some models HART is available on either
AO0 or AO0.
Active 4-20mA output
2
Control loop – AI0
1
+
-
+
-
Active 4-20mA input
4
Transmitter loop – AO0
3
A
+
-
+ -
2.1.1 Terminals
AI0
1 (+)
2 (-)
AO0
3 (+)
4 (-)
2.1.2 Electrical specifications
Control loop – AI0
Impedance
< 470 Ohm at 20mA and 9.4VDC
Linearity
< 0.1%
Temperature coefficient
0.025% / 1°C (Warm-up: 10 min)
HART (optional)
FSK, 1200Hz / 2200Hz 400-800mVpp
Galvanic isolated
Transmitter loop – AO0
Impedance
< 470 Ohm at 20mA and 9.4VDC
Linearity
< 0.1%
Temperature coefficient
0.015% / 1°C (Warm-up: 10 min)
HART (optional)
FSK, 1200Hz / 2200Hz 400-800mVpp
Galvanic isolated