What are these components from a Class 313?

[antharro]

Recently picked this up with some 313 bits. I have no idea what it is. Can anyone advise please?





[For folks who can't see the pics - it's an opaque rectangular item marked "eao Article 72-01058.1 Date of Production: 01/2016". There are various electrical specs on the ear. It has sealed connectors on both end which have four wires connected.]

 

[Prime586]

EAO (the name that's moulded into the encapsulation are a Swiss-based manufacturer of Human-Machine Interface components (i.e. pushbuttons, switches, panel indicators/LEDs and joysticks). they are very active in the transportation sector (here is a brochure of some of their rail-oriented products).

The production date of 2016 puts it into the timeframe of the Class 313 DDA refurbishments for Southern, which included new door opening buttons and door release sounders, so I expect it was fitted as part of that upgrade (the new door buttons fitted in the upgrade look like EAO Series 56 types).

As to what it is, the specs on the back imply the 4 wires are 3 signals and a ground, and it has an input votage of 170VDC and low input current limits. My guess is that it's a 3-channel opto-isolator used to provide low-voltage input signals into whatever EAO kit was installed in the refurb from the high voltage signals available from the train's existing systems.