Operating a relay

There are a few 24VAC relays on Ebay. Would they work on 85 volts (add resistor to bring that down) 25 cycles

I suppose the ring signal can be about 85 volts, but is normally about

If you want to use the phone line with the relay connected, you may need to add a series capacitor so it will not draw DC current when you go off-hook. Or you can sense the off-hook condition and disconnect the relay circuit when the voltage drops or the line draws DC current.

Paul

try a larger capacitor in parallel with the relay.

do you need the relay? could you use a NE2 (neon indicator) + photo-transistor optopcoupler instead?

A typical ringing voltage.

Graham

Thanks Guys for the input I got it I used a very small relay connected to a bridge rectifier with a cap in series on the AC side Works good Thanks

This article says 90 VAC at 20 Hz:

Here is more detailed information, that indicates 90 VAC into 5 REN:

It also says that it is 75 VAC in Europe.

Paul

:Is there any way to operate a small 12 volt relay with the ringing :voltage on a phone line. I have tried to use a bridge rectifier with :a capacitor but the relay chaters. Any ideas :Rick

I have done this many times using a 48V DC relay, bridge rectifier and 100uF electrolytic capacitor. The relay (I have a few hundred) is a Meisei M4-48H which has a 7,800 ohm coil. It works perfectly.

:On Wed, 14 Jan 2009 08:07:12 -0800 (PST), trickyrick wrote: : ::Is there any way to operate a small 12 volt relay with the ringing ::voltage on a phone line. I have tried to use a bridge rectifier with ::a capacitor but the relay chaters. Any ideas ::Rick : :I have done this many times using a 48V DC relay, bridge rectifier and 100uF :electrolytic capacitor. The relay (I have a few hundred) is a Meisei M4-48H :which has a 7,800 ohm coil. It works perfectly.

I forgot to say that the input to the bridge rectifier is DC isolated using a