Analogue Input Modules; Mtl5541/Mtl5541S/Mtl5541S-T - Repeater Power Supply - Eaton MTL5501-SR Instruction Manual

6 .4

Analogue Input modules

The analogue input (AI) modules support 2-wire or 3-wire 4/20mA or HART transmitters located
in a hazardous area; repeating the current in other circuits to drive safe-area loads.
6 .4 .1 MTL5541/MTL5541S (-T) - Repeater Power Supply
Single channel, for 4/20mA HART® for 2- or 3-wire transmitters
The MTL5541 provides a fully-floating dc supply for energising a conventional 2- or 3-wire
4/20mA transmitter which is located in a hazardous area, and repeats the current in another
floating circuit to drive a safe-area load. For HART 2-wire transmitters, the unit allows bi-
directional communications signals superimposed on the 4/20mA loop current. Alternatively,
the MTL5541S (-T) acts as a current sink for a safe-area connection rather than driving a
current into the load. Separately powered current sources, such as 4-wire transmitters, can be
connected but will not support HART communication.
Hazardous area
MTL5541
PWR
S
Figure 6 .20:
Top labels
for MTL5541
& MTL5541S
INM 5500 Rev 10
Safe area
6
5
4
Com
3
Tx+
2
Input
1
4/20mA
Terminal Function
1 Current input
2 Transmitter supply +ve
3 Common
10 Output +ve via 220Ω for HART apps.
11 Output –ve (+ve current sink)
12 Output +ve (–ve current sink)
13 Supply –ve
14 Supply +ve
7
8
9
MTL5541 MTL5541S
I
10
+
–
11
I
4/20mA
12
–
+
Load Load
Vs–
13
Vs+
14
20 to 35V dc
+
–
41