wiring of a French clock mechanism

[cornishben]

This is pretty far off topic but thought this would be the kind of thing you might like to exercise your cranial muscles on..

We bought an old railway station clock from a junk yard in France, circa 1960 or so (made by Lambert) and I'm just trying to work out how to wire it up to go on the wall!

It's 230v and has 4 wires and an earth so I'm trying to work out which to connect.  I've taken it apart and below is an image of innards and my sketch of the wiring.


It has two micro switches, I think there's one on the minute cog and one on the hour cog.  There is one indent on each cog so it seems the switches are 'on' continuously but released once per revolution. 

I'm wondering if these were maybe to send a signal to a digit display or to sound an hour dong or something, any ideas?

The switch function is to be normally closed in the top position and when pressed open this contact and close the lower contact.  It seems the clock will lose power once per revolution of each?

The obvious solution I guess is just to bypass the switches altogether, but I'm intrigued to their function.

[johnrae]

As shown, once the yellow wire switch is opened the "clock stops never to go again"  Now there's a line for a suitable song.

Are you sure the common on that switch is connected to the motor terminal.

It's more likely that the motor is permanently wired and the switches are used to provide pulse signals to some other device, such as a repeater clock.

[clockmanFR]

If it is mains then its a synchronous motor running on 50hz however sometimes the motor needs to be started to get into phase, and therefore rotate at the right speed for the gearing. Later the motor was designed to self start but then could run backwards. Any way they got it right in the mid 60's. 4 wires, does each give a reading on your meter in ohms? 2 wires could be for a capicator start winding?

[ericw]

At what times(s) do the switches operate?
They might be used to set the clock by switching supplies when a specific time is reached.
This method was used on pulse driven clocks to get them into sync.

[cornishben]

If it is mains then its a synchronous motor running on 50hz however sometimes the motor needs to be started to get into phase, and therefore rotate at the right speed for the gearing. Later the motor was designed to self start but then could run backwards. Any way they got it right in the mid 60's. 4 wires, does each give a reading on your meter in ohms? 2 wires could be for a capicator start winding?

I've just looked high and low for my multimeter but to no avail so can't get a resistance reading.
johnrae - it's definitely wired as shown in the pic, I just checked.  This is what seems odd as if it was providing pulse outputs then it wouldn't make sense to interrupt the power to the motor. Maybe as ericw says it is to provide synchronisation because there doesn't seem to be any way to adjust the time, it just starts running.   It's a bit hard to work out the time(s) that the switches operate but I 'think' one is once a hour and the other once a day.

Think I'll just have to wire the motor up directly and turn it on at exactly the time it happens to be set to :-)

[cornishben]

Hmmm. wired the motor up directly this morning and it goes kinda fast, I'm going to be up for retirement in a couple of years at the rate it's turning  so I assume there was so kind of external input that told it to 'tick' on one minute or similar..   might have to replace the mechanism I think :-(

[clockmanFR]

Okay, Seems to me you have a waiting train, (no not a train in a station) but a clock mechanism that awaits and gets into line with a master clock. Also the Hz frequency may be different now to then.

A waiting train allows the clock to run normally but slightly fast and every minute or hour the clock his stopped momentary to allow the master clock to send a pules to start the clock again.

Hence two windings in your motor, so you connect with one set of wires using your micro switch wired in to your motor so that the clock then stops at the micro switch. A master clock, (rare as rocking horse -hit) then sends a pulse to the other winding on your motor that starts your clock going again and as soon as it is past the micro switch the clock runs again and the pulse from the master clock is only sufficient just to get your motor running past the micro switch.

I am not aware of this French system but we in UK did use something similar for Railway time keeping.

 Because, A well know Port in Devon, railway inspector "how do you set your time for the clocks" station master, "i await the black ball/cone to drop down at the harbour", to the harbour master, "how do you set your time", I have this telescope and i watch the clockmakers regulator in the window of his shop in town", to the clockmaker, "how do you set your time", "i look to when the ball/cone drops at the harbour masters office".  Very funny but sadly very true.

And because of rail accidents universal time was an absolutely important in any country as it headed into industrialisation.