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I suspect this switch isn’t functioning correctly and would like to replace it but can’t find one similar. What sort of switch is it?
The front is a push with two states (in/out) and has a bulb to indicate on/off (though that’s not currently working). It’s probably from early 90s or late 80s.
This is a similar switch that I got a better photo of, though it has extra wires out. The switch of interest is in the background.
The diagram on the side is pretty clear -- the top terminals are for a bulb, the "middle" (one up from the bottom) terminals are a NC contact, and the bottom terminals are a NO contact. It's almost, but not quite, a SPDT switch -- it's more like a DPDT switch that's missing some terminals.
BUT looking at the picture, it's running current from the contacts through the bulb. It may be that the burnt-out bulb is an essential part of the circuit (possibly for safety reasons, to never energize a circuit unless there's an indicator light).
Dig through the rs-online site; this should be pretty obvious.
If all you need is a replacement, and looks don't matter, then by the diagram and the wiring, only the NC section (and possibly the bulb) is being used -- so you just need a normally-closed (or closed-when-out) SPST push-push switch with a bulb.
It’s either a momentary or toggle push-push latching switch . What makes you think it is not Functional?
They do make cheaper ones too. https://uk.rs-online.com/web/p/push-button-switches/0319449/
