Old (wall)telephone ring motor sucking too much current?

Using Arduino Motors, Mechanics, Power and CNC
#1

Hi all,

We are modifying an old telephone, the ones which we're mounted on a wall.
The thing is that we want to use the ringer (you know the old trrrrrringggg soundmaker).

I've connected it to a relay and powered it externally. My adapter has a led on it, whenever the ring goes off the led on my power supply will turn off. This makes me think that my power supply isn't powerful enough!? I'ts like the ringer is sucking all the power.

I also connected a diode on the ringer so that's ruled out.

I connected my relay like this: http://faculty.purchase.edu/joseph.mckay/hacking_everyday_2012/images/arduino_relay.jpg
and as I mentioned I also have a diode on the + and gnd of the ringmotor.

questions:
1.Is this happening because the thing is old (inefficient made stuff)?
2.How can I solve this issue? power it with a power supply with higher current(A)?

Current power supply for just the motor: 5v 500ma (should be enough to just ring the thing a few times ?

#2

The bell was 50V IIRC.

#3

meaning?

Is there any way I can use it ?

#4

Meaning the phone line voltage is 50V and that's what the ringer wants.

Whatever would we do without google?

#5

thanks man,

Is replacing the motor inside the bell with a new motor fastest/easiest way ?
something like a little stepper motor which will turn around and hitting the bell ?

#6

How old is "old" ? 1980's old ? 1950's old ?

Old phone stuff works off 45 V DC IIRC

#7

But the ring was AC.

#8

Is replacing the motor inside the bell with a new motor fastest/easiest way ?

There is no motor in a bell in a telephone. At least not the ones I have seen.

You need to supply the phone with a much higher voltage, get a new power supply.

#9

You need a relay off the Arduino to switch 50 Volts AC to the ringer solenoid. By the way, the bell ringer is a solenoid. Something like a relay, only with a hammer in place of contacts. The AC current makes it vibrate the hammer. May be able to get away with a bit less voltage. Maybe a 24 to 48 Volt AC wall wart 'Adapter'.

#10

steinie44:
You need a relay off the Arduino to switch 50 Volts AC to the ringer solenoid.

No.
The thing is that telephone bells do not work at the same AC frequency as the mains.
See this:-
http://www.epanorama.net/circuits/telephone_ringer.html

#11

michinyon:
How old is "old" ? 1980's old ? 1950's old ?

Old phone stuff works off 45 V DC IIRC

48vdc nominal when on-hook (hung up), around 6 vdc when off-hook (handset picked up) @ 600 ohm nominal load impedance. Ringing voltage is 90vac @ 20 Hz (riding on the 48 vdc offset voltage) and I don't recall the ringing current capacity but I'm sure it can be found out.

#12

Per Grumpy Mike's link

United States is 20 HZ and in Europe is typically 25 Hz, it can be any frequency between 15 and 68 Hz. Most of the world uses frequencies between 20 and 40 Hz. The voltage at the subscribers end depends upon loop length and number of ringers attached to the line; it could be between 40 and 150 Volts.

#13

michinyon:
How old is "old" ? 1980's old ? 1950's old ?

Old phone stuff works off 45 V DC IIRC

the phone looks like this one: http://www.payphone.com/images/T/GTE-1000B-Traditional-Wooden-Wall-Phone_300x300.jpg

so it's this old..

steinie44:
You need a relay off the Arduino to switch 50 Volts AC to the ringer solenoid. By the way, the bell ringer is a solenoid. Something like a relay, only with a hammer in place of contacts. The AC current makes it vibrate the hammer. May be able to get away with a bit less voltage. Maybe a 24 to 48 Volt AC wall wart 'Adapter'.

yes I opened it up and indeed it's a solenoid with a 'hammer'.

The ringer works on all voltage, but I don't know what voltage is good. even on 3volt it rings. But as I mentioned, it sucks all the power from the adapter.

#14

An AC solenoid fed with DC is going to pull a (much?) higher current, since with AC
the inductive reactance is the current-limiting factor, not the winding resistance.

#15