12
LEVELtrol-II Installation & Operating Instructions
4.3 Wiring In Hazardous Areas:
Examples using Barrier (MTL4755ac for RTD)
1
2
3
4
4-20
Q/
∆
P
+
–
2 1
3 4
28V
Diode
24V Out
4-20mA In
Common
4-20mA
Transmitter
Hazardous Area
Safe Area
Flow Input
Level Input
Hazardous Area
Safe Area
Temperature/Density Input (4-20mA Transmitter)
4-20
T/D
–
+
1 2
4 3
28V
Diode
1
4
8
24V Out
4-20mA
Temp. or Dens.
Transmitter
4-20mA In
Common
Temperature or
Density Input
(4-20mA Transmitter)
Hazardous Area
Safe Area
Temperature Input (RTD)
Temperature Input
(RTD)
4
5
6
7
8
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Common
RTD Excite (+)
RTD Sense (+)
RTD Sense (–)
3-Wire RTD
