Gents Gents C7 Pulsynetic master clock internal circuitry

[dennishoy]

Good evening folks.

I've just acquired a Gents C7 master clock from an 'electrical engineer'.
Unfortunately despite talking a lot about his years of experience of fixing just about everything, I would be surprised if he could change the batteries in a torch and get them the right way round.

The clock 'was working' according to him but when I went round to collect it, not surprisingly it had stopped. We took it off the wall, and amazingly, it was fixed with a single screw into a hollow plasterboard cavity wall. I got the clock home, but thought I should check it out before connecting anything.

This C7 is a late one numbered 13507 with the black numbers in a circle on the white, square dial.

The contact gap was hopelessly wide so I adjusted it and closed it up so I could check the coil resistance.
I have a problem in that when the contacts are closed by hand, the resistance across the supply drops to zero, i.e. the supply will feed into a short circuit. The rheostat that is supposed to adjust the current has no effect. I have checked the coils and they are not short circuit.
I have concluded that somebody has messed around with the wiring.

I have the manual, but that only shows how to connect slave clocks and put a system together.
I really need an internal wiring diagram for the clock in order to check for the correct wiring, but this is not shown in the manual.
There are several terminal block where wires could be interchanged, but without the diagram, this is hard to determine.

Please can anyone help with an internal wiring diagram?
Thanks in advance.

 

[dennishoy]

I've attached some pictures...... does the supply go between '1' (-) and '2' (+) ?
If so, then why does the label say 'No.2 Terminal for Transistor Relay only?
This is a bit confusing.

Thanks in advance for any help.

 

[Hans Vrolijk]

Here a C7 diagram, be it with extra connections for "recorders", registrating the activities of engines like looms etc.

 

[dennishoy]

Many thanks Hans and greetings from the UK.
This is exactly what I was looking for.

I'm going to remove the mechanism and check the wiring point-to-point and I'm sure it's been altered.
As far as I can see, the only item missing is the 2uF capacitor across the contacts, but this would not stop it working.
I will let you know what I find but THANK YOU again Hans for your help.

 

[mr.ridout]

How do you adjust the internal rheostat in a Gents C7 Pulsynetic? Does it turn and lock down, or just slide or maybe lift and slide? I cannot get it to move and I am afraid of breaking it by turning it too hard.

 

[Edwardo]

Hi and welcome
Loosen the screw on the black knob and it should slide up and down
Hope this helps

 

[mr.ridout]

Thanks, I will give it a try. The oblong knob looks like it should be turnable. Glad I didn't try too hard. Mick

 

[mr.ridout]

My Gent pulsynetic will not keep running. I just got it about three weeks ago and I have adjusted the resistor and tried different batteries. The latest battery was a 12 car battery that I know is hot. I set the resistor at 17 ohms so that amperage is .22A (no slaves other than the one in the transmitter. The gravity lever goes down every 30 seconds and when the contacts touch it pops back up. It will function like this for about two minutes and forty-five seconds and then there is not enough movement in the pendulum for the catch pawl to catch the next ratchet tooth. Then the pendulum slows and stops. While running, if I pull down on the advancing string so it impulses three times, it pushes the pendulum enough to continue running for another couple of minutes.

Hopefully there is someone out there who is really familiar with these clocks to advise me. I was thinking of adjusting the nuts at the tip of the pendulum suspension to move the pendulum a little more to the right so the roller will make longer contact with the pallet.

Any other ideas?

Mick

 

[Edwardo]

This clock will happily run on 6v


1/ Is the the lever resetting in a snappy fashion?

2/ Is the clock plumb?

3/ With the pendulum stopped does it line up with the center of the scale at the bottom of the cabinet?

4/ Is the case leaning forward or backward?

// There are brass screws in-bedded in the cabinet under the door frame and on the left
// These are for plumbing the clock

5/ Check the roller that impulses the pendulum

6/ Check all moving parts for smooth operation

7/ Have you tried to adjust anything mechanical, if so what?

 

[mr.ridout]

Thanks for getting back to me.

It does snap back, but I am not sure how much is enough. I will say that I had heard that it is quite noisy, but it doesn't seem that noisy to me. So maybe it isn't snapping hard enough.

I did plumb it and the pointer is at exact center.

I did not plumb the wall. I will have to check and make sure that it is.

The roller spins freely. I took off the pendulum crutch and cleaned and oiled it. I did the same for the ratchet, just oiling the pivots. (it spins freely)
Everything seems to operate smoothly.

I did notice that the roller hits the top of the pawl before running down the face. And the pawl seems to touch the roller before the gravity arm snaps back up. I thought that might be slowing it some.

The only mechanical adjustment I made was to bend the ratchet stopping lever wire a little to move the ratchet teeth a hair so the arm would make it past each tooth. I did this after much testing with different voltages and resistances.

 

[Edwardo]

I did notice that the roller hits the top of the pawl before running down the face. And the pawl seems to touch the roller before the gravity arm snaps back up. I thought that might be slowing it some.

That could be your problem

The roller should ride just above the pawl and make no contact with anything until the arm drops

The roller should land just before the pawl and then roll down

You can adjust the latch by loosening the two screw at the top with an angled screwdriver

Warning

If you move the latch up to high the arm will not rest


If you bent the click to allow it to pass the teeth then either the clock has been messed with or the pendulum is not swinging strongly enough

You should be aiming for between 3 and 4 on the pendulum scale


Note

Most of these clocks that I have serviced are badly adjusted

The felt pad above the arm wares out and people tinker with the settings to make the clock run

In most cases this works, but it makes the clock very noisy

A well adjusted pul-syn-etic movement is relatively quiet

 

[Rick Hunter]

Good Evening All,
I am new to this forum & here as I have just purchased a C7 from a dealer in Perth.

The clock has the serial number on the case of 2477 which , I think, dates it to about December 1925.

It has the name ENNIS & SONS on the face who were a Perth firm.

Any other historical info would be gratefully received.

I have adjusted it according to Derek Bird's instructions and it is running quite nicely.

Rick

 

[Edwardo]

Hi and welcome

The Ennis Family ran a jewellery business and, among other things did public clock conversions

I think Paul Ennis still maintains the Perth town hall clock so you could try contacting him

Try calling the town hall

Back in the day Gent supplied their clocks to anyone and were happy to re-badge them

Let us know how you get on

 

[mr.ridout]

Edwardo, It has been a couple of months since I was on. Just got time to work with the Pulsynetic and I watched it very closely. I think it is NOT resetting in a snappy fashion. I think it is lagging and then it is pushed back up a bit by the pawl on the pendulum crutch before it snaps away. I do not know how to adjust that. Mick

 

[mr.ridout]

On the back swing the roller actually lands on top of the pawl, rolls backwards just a little and then rolls forward and down the inclined part of the pawl. Then on the fore swing, it rolls just a little up the incline and then the arm snaps up.

 

[mr.ridout]

I have been watching and playing with it more. It will run for about 2-1/2 to three minutes and then stop. If I pull down on the advance cord and let it cycle about five times, when the pendulum has reduced arc, then it builds back up and will run some more. If I pull down the cord at half of the 30 second cycle, it will continue to run indefinitely. So it seems as though it is something other than adequate snap back. Since the impulse is gravity and should be constant, then perhaps something is dragging on the train. Thoughts?

 

[Edwardo]

Hi
Sounds like a switch adjustment is needed
without a video I cant be sure
The roller should roll at least half way down the "inclined part" before the contacts meet
Adjusting this switch is a tricky operation and the back stops will needed to be tweaked as well
If done wrong the clock becomes erratic and noisy.
If you can find a way of videoing it it will speed up the diagnoses

 

[mr.ridout]

The Pulsynetic ran all through Christmas and for about two weeks and then just stopped. I started it again and it ran for about 15 minutes. Then I started it again and it ran and ran. ran about a week and stopped again. Sounds like maybe dirty somewhere, but I have cleaned and oiled every place that I can find. I am also suspicious that my 6v batteries might not have sufficient amps to run it. Or maybe it is using them up really quickly.

BTW, Edwardo..... I recently got a Synchronome plate with most of the hardware on it. Do you know much about them?

 

[Edwardo]

Hi

I am assuming the case is plumb both side to side and back to front

There are brass screws in the case inside the door top and bottom also on the left

These are for plumbing

If it is plumb it sounds like it could be an electrical problem

This could be caused by atmospheric conditions eg sudden change in temp or humidity

or simply a poor power supply / connections or contacts

When the clock is running what is the reading on the scale at the bottom of the case

Please give me the number on the left and on the right of the scale that the pendulum reaches

They should be the same

EG “3” or “3.5”



Re synchronome there is a lot of info out there

Is there something in particular you need to know?

Cheers

 

[bruce linde]

check the sticky thread on gents master clocks at the top of this forum... within that thread you will find documentation on how to make sure they're set up correctly.