Rewiring an Urmet door entryphone handset

Is this a single or multiple unit? If single, remove the door unit and check the colours there. I'd expect the tag strip to have matching numbers, etc, to identify the terminals. If a multiple installation, ask to look at a neighbours one?

As regards any internal wiring again looking at a second unit would be the easy way unless a circuit diagram can be found. Otherwise it's a question of working out the circuit of the device yourself. Which could be difficult.

However, a quick Google shows installation manuals are available in PDF format from Urmet's Italian site. But you'd need to know the model.

Doh. I never thought of that! It's a multiple one for a whole tenement. The simple answers are always the best!

Thanks,

Dave

Dave, one other thing if you don't mind - is it safe to work on these things while the whole system is still on? Am I in danger of electrocuting myself?

Cheers,

Dave

Try safelink.co.uk they are very helpful.

No. :-)

It's probably 5 wires, the wires are usually Common, Mic, Speaker, Buzzer, Lock. A button shorts Common and Lock to activate the door release downstairs. Common and Mic should usually be a twisted pair to reduce hum.

In a tenement you are quite likely to find Common, Mic, Speaker, Lock being the same colour (and in parallel across all handsets) but Buzzer may be a different colourn wire as it's the individual call wire to the flat.

On Urmet 1131 and 1132 phones, IIRC

CA is call (buzzer)

Owain

It's low voltage, but if you short something out you might blow the speech unit and knock out the whole system which will not endear you to your neighbours.

Owain

Thanks for the help Owain.

Cheers,

Dave