Saab TankRadar PRO - Connecting HART devices

Saab TankRadar
®
Pro Electrical Installation
3-7
Edition 2. Ref. No: 306010E
X1
Junction Box
EEx e
1
2
3
4
5
100-240 VAC
or
24-48 VDC
123
456
78
9
250 Ω
V
s
X1
Junction Box
EEx e
1
2
3
4
5
100-240 VAC
or
24-48 VDC
123
456
78
9
Voltage compli-
ance 7-30 V
Input impedance
<300 Ohm
Connecting HART devices
Active output (internal loop supply)
Passive output (external loop supply)
A hand-held terminal or
a HART modem should
not be connected di-
rectly across an external
power supply. Instead,
it should be connected
across a load resistor of
about 250 Ω.
For Pro gauges with active
output a hand-held terminal or
a HART modem can be con-
nected as follows: