MTL5511 - switch/Proximity detector interface

Digital Input modules
The Digital Input (DI) module range offers solid state or relay output switches in a safe area that respond to input switches located in a hazardous area. Single or multiple channel (2 or 4) options are available, as well as Line-Fault Detection (LFD).
Modules with LFD can recognise open or short circuit conditions on the input wires going to the field sensors, and some DI modules have the facility to reverse the effect of the input on the output i.e. phase reversal.
These options are chosen with switches located on the edge of the module on the hazardous area terminal side. In some applications it may be easier to set these switches before fitting the module to the DIN-rail.

MTL5511 - switch/Proximity detector interface
Single channel, with line-fault detection
The MTL5511 contains a changeover relay, which enables a safe-area load to be controlled by a
switch or proximity detector located in a hazardous-area.  When selected, the line-fault detect (LFD)
facility detects open or short circuit conditions in the field wiring and also indicates this on the top of
the module. Line-Fault Detect and Phase Reversal for the channel are selected by DIL switches
on the side of the module and output is provided by the changeover relay contacts.
See page 18 for LFD and PR switch details. Channel 1 only switch settings apply.
For switch sensor inputs, with LFD selected, make sure resistors (22kΩ and 680Ω) are fitted.
note: For reliable, long-term operation the load on the output switching relay should be not less
than 50mW, e.g. 10mA at 5V DC.