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INM MTL SUM5 Rev 1
5
INSTALLATION – MODULES
5.1 Terminals – pre-installation
The module base must be chosen to match the status of the field wiring; intrinsically safe
(IS) – blue module base, or general purpose (GP) – grey, see table below. The principle
distinction between the two is that the MTL4-BSIS and MTL4-BSISR terminal bases
contain the necessary diode and resistive components to provide the intrinsic safety
protection for the hazardous-area field wiring.
After that, the only choice to be made is whether the module base requires a relay for a
switched contact DO output.
Terminal bases – by application
Channel operation
I.S. field wiring
(Zone 0, IIC, T4-6 hazardous
area if suitably certified)
General purpose field wiring
(Zone 2, IIC, T4-6 hazardous
area if suitably certified)
AI
MTL4-BSIS
MTL4-BSGP
AO
MTL4-BSIS
MTL4-BSGP
DI
MTL4-BSIS
MTL4-BSGP
DO
MTL4-BSIS
MTL4-BSGP
DO - with switched contacts
MTL4-BSISR
MTL4-BSGPR
WARNING!
Do not install IS and general-purpose terminal bases on the same carrier!