4.6ELECTRICAL CONNECTIONS

All field wiring connections are accessible by removing the lower lid, which is secured by two screws. Note that it is the responsibility of the installer to observe all local regulations and approval requirements, and to use cable to suit the environmental requirements of the particular application. Obtain and check any hazardous area work permits required before applying power to the MSM400.

The diagram below shows the layout of external connection terminals: all terminal blocks are suitable for wires 0.5mm2 to 2.5mm2 (26-12 AWG). Insulation should be stripped back 7mm.

Ensure wiring is suitable for the load current and the insulation is suitable for the voltage, temperature and environment of the installation.

Note that in intrinsically safe systems, apparatus connected to the MSM400 must not be supplied from a voltage greater than 250V rms or 250V DC.

FUSE 200mA

K7941

Figure 9: Connection Terminal Layout

Note that not all of the labelled terminals are functional in this version of the MSM400. The functions available are listed below :

CONNECTION DESCRIPTIONS :

Terminal

Label

Function

 

 

1

RX

A

Sensor Cable

 

 

2

RX

B

Sensor Cable

 

 

3

RX

SCN

Screen for 1+2

 

 

4

TX

SCN

Screen for 5+6

 

 

5

TX

A

Sensor Cable

 

 

6

TX

B

Sensor Cable

 

 

7

TRIGGER 0V

Ground ref for Trigger inputs

 

8

TRIGGER D1

Digital input No 1

 

 

10

TRIGGER 5V

5 V output

 

 

16

I out Io

Current output (4-20mA)

 

17

I out 0V

Current output zero ref terminal

 

18

I out 24V

Current output 24 V DC loop power : refer to Fig. 10

19-21

RELAY 1

NC-C-NO Relay output

terminals for Relay 1

 

22-24

RELAY 2

NC-C-NO Relay output

terminals for Relay 2

 

25

DC out 24V

Output of 24 VDC for powering external devices.

26

DC out 0V

Ref for DC output

 

 

27

DC in 24V

Positive supply at 24VDC to the MSM400--ie DC power input

28

DC in 0V

Ref terminal for DC supply input

 

29

Mains L

AC power input 115/230V, Live terminal

NB: SELECT 115 or 230V

30

Mains N

AC power input 115/230V, Neural terminal

ON SWITCH ABOVE

31

Mains E

Protective Earth (PE)

 

THESE TERMINALS

NOTE 1 The sensors are symmetrical, so either of the two cable pairs can be chosen as "Tx" or "Rx

IP258

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Image 13
Emerson MSM400 manual Terminal Label Function