clock project, need help in motor replacement

[Walz]

Hello, I have been working on clocks all my adult life. Mostly the vintage ones from the early 1900's. I have a few electric clocks from the 1930's that I have restored.

On to my latest project, I have a clock manufactured by the Electric Time Company, and I'm wanting to replace the motor from a 24vac to a 110v. I need some help in where I can locate one. The reason for my motor switch is the system that the clock movement works with is a controller and acquiring the electronic controller is $900.00. If I can get a 110v motor it would not cost that much.

Motor information:
10 tooth gear
24vac 60Hz 150ma-2.5w
Saia-burgess made it

If I can find out who makes the movement that would give me some place to start.

Thanks for any help.

 

[harold bain]

hi, Walz, welcome to the message board. Try contacting Electric Time. I'm sure they could source you a motor:
http://www.electrictime.com/

 

[shutterbug]

More important than the motor is the RPM (and direction) requirement. Be sure to check that.

 

[Walz]

More important than the motor is the RPM (and direction) requirement. Be sure to check that.

That is what I need some help on.

 

[Walz]

hi, Walz, welcome to the message board. Try contacting Electric Time. I'm sure they could source you a motor:
http://www.electrictime.com/

Made contact with them first, they could not provide me with an answer.

 

[Walz]

Wow that's interesting, no one has any information on this, it must be something that's a mystery.

Well it's time to dust off my books and start to read up on movement & motors again. I was hoping to find another person that has done this before, no such luck. On to another parts unknown project, thanks anyway.

 

[Rogerstar1]

Walz- When you get iif figured out please consider posting an update here so the rest of us can become elucidated.

 

[eskmill]

A couple of days ago, Walz commented that he'd already contacted Electric Time about a replacement motor and that Electric Time "....... could not provide me with an answer."

Possibly Electric Time didn't understand your question. The company, I as far as I know (I have read their postings on this forum from Electric Time), assembles large electrically driven tower and street clocks. Their street clocks are seen in many US cities.

I think, after studying your photos, the simplest solution, since you aren't able to locate a 120 volt model of the clock motor is to install a small transformer to reduce 120 volts to the required 24 volts. The nameplate on your switch box implies that the current is 200 MA or two-tenths of an ampere. A very small transformer such as a residential door bell transformer should work just fine if indeed, the motor is a simple two-wire 24 volt 60 Hz AC synchronous motor and not a DC stepper motor.

Another source is the actual supplier of the motor as noted on its label or, Saia-Burgess a large US supplier of all kinds of electric motors.

Finally, I'm surprised that Electric Time could not assist. Try asking for Thomas Erb at Electric Time.

 

[Tinker Dwight]

I agree with Les.
A door bell transformer would work. They are available
at any hardware store.
Tinker Dwight

 

[Walz]

From what I have found out is the following, the clock runs on 24v the controller is 900.00 to make it run. The clock is a 24v impulse clock, so I would need to purchase a controller which is not a option, or find a motor that is geared to the movement. The manufacturer did help me, however the option is to much money. So I need a solution to this problem, a motor that is reduced to the speed I need to operate the clock would be the best option. I'm thinking on the principle of Telechron reduction gears.

 

[eskmill]

Walz and all. It is unfortunate that you are unable to obtain any useful information about the motor you need from Electric Time Inc.

The SAIA Burgess motor shown in your photo with the part number UDS1 UG4 D30 DNNA is no longer listed as obtainable from SAIA Burgess (Thompson). It's not in their catalog.

You have to wonder where Electric Time obtained the motor.

However, there is a 120 Volt AC 60Hz SAIA Burgess motor similar motor offered for sale at less than forty dollars on an auction site.

I suggest you Google for a motor with the following part number:
Saia-Burgess UDS1UJ1M50ANN2M

We have to wonder what clock you are working on. Electric Time Inc. is noted for producing clocks for outdoor and special use not clocks usually found in domestic settings.

What are trying to do with this 24 volt motor assembly that now needs a nine-hundred dollar controller?

 

[Tinker Dwight]

I still don't see why one can't use a 24V door bell transformer.
It came with an impulse supply but it is still a 60 Hz motor.
Why not give the transformer a try. Who knows, it just might
work.
Tinker Dwight

 

[davefr]

Try:
Herbach.com

They have a wide selection of synchronous motors in various RPM's and Torques.

You'll likely need to transfer the 10 tooth gear to the new motor.

 

[Walz]

This clock runs on a impulse driver, I've been researching the clock and I'm convinced that if I can find a 24V ac impulse driver for it, it will work.
When I first started with the clock I was under the impression that the clock was a setup like the telechron clock movement, and that is why I was looking for a 110v motor.
Now I'm focusing in on a 24V ac impulse driver to run the clock. I've tested the clock by powering up the clock with 24V ac power and it works great except the clock is not going to work on a constant stream of voltage accurate, it is a impulse movement and now I have to locate the correct impulse driver that is set on 24V ac and not 24v dc.

I thought that this clock movement was researched by another person and it would be easy to retrofit, and I was wrong, no one else has written about this movement, and it's simple to service, it's heavy duty, and the movement is well built. No matter what, I'm going to keep the movement and find a solution to the problem.

Electric Time really makes a great clock, like the best made, the craftsmanship is really good, the quality materials are great, it's nice to see a product made in the USA by craftsmen who are still building great clocks. I bought this for only $50.00 ($4,000.00 new) and it's going to be well worth investing time to find a impulse driver to make it run. I'm putting the clock in my garden room of the house, and yes it's a room that we have for plants, inside the home. The clock will fit right in with the decor. I'm not giving up on this excellent clock that is a well crafted piece of American art. A solution is somewhere and I'm going to find it, keeping the movement and motor the same.

If anyone knows where I can find a impulse driver 24V ac., I would really like to find one.

 

[harold bain]

It would not be difficult to build one using a 110 volt 1 RPM motor driving a cam that activates a microswitch once a minute, if that is the period required. Finding a 24 volt transformer for the pulses would also be relatively easy to find. I think it is doable. What does the actual clock look like?

 

[Tinker Dwight]

Unless you need a super accurate clock, why not just
leave it run on AC.
In the first pictures, there is a PC board. Is that the original impulse board?
If so, what is wrong with it?
Tinker Dwight

 

[Walz]

It would not be difficult to build one using a 110 volt 1 RPM motor driving a cam that activates a microswitch once a minute, if that is the period required. Finding a 24 volt transformer for the pulses would also be relatively easy to find. I think it is doable. What does the actual clock look like?

The clock needs a 24V ac pulse and that is the issue, not "dc" which I've found online.

 

[Walz]

Clock:

 

[praezis]

Hello,

it is no rocket-science to put company and type ("Style:") into a search engine. You will find that HMI stands for H-type Minute Impulse Movement. And that alternating 24-V pulses are needed.
So this thing is an ordinary 24V slave movement. Pulses are the European style alternating type.

Slave controllers are offered in the web for far below $900 ...


Regards,
Frank

 

[eskmill]

The clock needs a 24V ac pulse and that is the issue, not "dc" which I've found online.

I think some electrical definitions might help on this issue.

Alternating or AC pulses are sinusoidal....much like blood pressure. There are pulsations which rise to a peak then decrease to the lowest amount of pressure or voltage. The rise and fall rates are "sinusoidal" rising and according to the mathematical value of the sine of the average pressure or voltage . (24 volts in your application)

Slow alternating current impulses of 50 or 60 cycles per second are amenable to magnetic devices with small iron magnetic parts that can change from north-to-south without much reluctance. The iron parts of an AC motor or transformer have to be made of small iron pieces. Large pieces of iron are reluctant to change their polar magnetism.

Direct current impulses are usually either full-on or fully off. DC impulses are useful for certain applications but the very sharp or steep rise and fall from off to on and back to off is usually only good for incandescent filament lights or for circuits designed to handle the instant rise from zero volts to the peak voltage and back down to zero volts.

DC impulses, when connected to a magnetic device, like a motor or transformer, always causes an "echo" impulse in the circuit, generated from the collapsing magnetism that occurs in the circuit. The "echo" or harmonic can be both harmful or desired depending on the design of the circuit.

DC impulses are used in special electric motors that have their iron magnetic cores made of powdered iron bonded as a ceramic. They're generally called "stepper" motors and they don't work on common AC.

I hope my simple explanation is helpful.

 

[harold bain]

The clock needs a 24V ac pulse and that is the issue, not "dc" which I've found online.

Yes, and my solution would give you a 24 volt AC pulse once a minute, if that is what you require.

 

[Tinker Dwight]

I don't believe it is a 1 minute impulse clock. Clearly not what the
motor runs on.
Am I confused. It is a 60Hz motor. It seems the control circuit was
driving it at 60Hz or close to. It has an output rate of 2 RPM ( 30 s ).
That is with 60Hz, not 1Hz.
Even if the original clock was driven by a 60Hz DC pulse, I see no
reason It can't be run from a 24V AC door bell transformer.
That is, unless he has 50 Hz line.
What am I missing here.
I find it hard to believe that any engineer would try to do exact control
of a 60Hz synchronous motor by pulse 60Hz on and off.
Tinker Dwight

 

[harold bain]

Tinker, explain a "60 hertz DC pulse" please?

 

[Tinker Dwight]

Tinker, explain a "60 hertz DC pulse" please?

You use an H bridge output that change the polarity at 60 Hz. A typical way of driving
stepper motors but could be used to drive a synchronous motor with the proper snubbers.
Tinker Dwight

 

[Walz]

I don't believe it is a 1 minute impulse clock. Clearly not what the
motor runs on.
Am I confused. It is a 60Hz motor. It seems the control circuit was
driving it at 60Hz or close to. It has an output rate of 2 RPM ( 30 s ).
That is with 60Hz, not 1Hz.
Even if the original clock was driven by a 60Hz DC pulse, I see no
reason It can't be run from a 24V AC door bell transformer.
That is, unless he has 50 Hz line.
What am I missing here.
I find it hard to believe that any engineer would try to do exact control
of a 60Hz synchronous motor by pulse 60Hz on and off.
Tinker Dwight

When I put 24v ac to the clock the hour hand moves like a minute hand, clearly it's a impulse type, when I look at the specifications the controller sends signals to the movement to move the hands. Now that is where I screwed up thinking the movement motor was constant power and it had a reduction gear like the Tlechron (mispelled) but I was wrong. The only other way would be a impulse set up. I may be wrong again however this is a puzzle I'm enjoying to figure out. If I find a crystal, 60 second impulse 24V ac I think I can get this to work correctly for my home usage.

 

[praezis]

I don't believe it is a 1 minute impulse clock. Clearly not what the
motor runs on.

Tinker,

I must agree with you, the motor label clearly says 24V ac / 60 Hz.
Looking again on this document: can it be, the movement runs on a mix of 60Hz ac and 1-min pulses?
Some seconds AC just to make the 1 minute movement, then wait for the 1-min pulse that synchronizes the clock and serves as the real timebase...

Frank

 

[Tinker Dwight]

Tinker,

I must agree with you, the motor label clearly says 24V ac / 60 Hz.
Looking again on this document: can it be, the movement runs on a mix of 60Hz ac and 1-min pulses?
Some seconds AC just to make the 1 minute movement, then wait for the 1-min pulse that synchronizes the clock and serves as the real timebase...

Frank

It might but I only see the two wires for the motor. There would need to be
a solenoid on the movement to do the advance/retard with.
No matter what, using a 110volt motor of the otherwise same specification
will not run any different than the 24V motor on a door bell transformer.
From what I can see of the circuit board, I suspect it creates the 24V pulsed
DC at 60Hz to run the motor. It may use quartz or radio reference as a time standard
and is connected to a DC supply so that it will not loose time if the AC is
lost.
I could be wrong but maybe we haven't seen enough pictures of the parts.
I would like to see the circuit board to see what is there.
Tinker Dwight

 

[harold bain]

A picture of the movement from the back of the clock might help. Doesn't sound like anything I've heard of.

 

[eskmill]

I strongly suspect that Walz has led us down the "garden path" leading us to believe the apparatus he bought at auction was a part of a clock manufactured by Electric Time Inc. and indeed it may have been a part of one of their clock systems.

We have no way of knowing for certain that the simple gear motor shown in Walz's photos is the one originally assembled by Electric Time Inc. It may be a "marriage" of assembled clock parts. :cyclops:

With no help from the Electric Time company or wholesaler of electric components Saia-Burgess, we are collectively in my opinion simply guessing in the dark.

In a way it has been an interesting discussion and in another way a "fool's errand" to conjecture an acceptable solution.

I wish I was mistaken.

 

[Walz]

I strongly suspect that Walz has led us down the "garden path" leading us to believe the apparatus he bought at auction was a part of a clock manufactured by Electric Time Inc. and indeed it may have been a part of one of their clock systems.

We have no way of knowing for certain that the simple gear motor shown in Walz's photos is the one originally assembled by Electric Time Inc. It may be a "marriage" of assembled clock parts. :cyclops:

With no help from the Electric Time company or wholesaler of electric components Saia-Burgess, we are collectively in my opinion simply guessing in the dark.

In a way it has been an interesting discussion and in another way a "fool's errand" to conjecture an acceptable solution.

I wish I was mistaken.

This is 100% original electric time manufactured clock, no way was it or is a hodge podge clock. I think we are on to something here and I think that we can figure this out, more brain storming is required I think.

 

[Walz]

More photos of the circuit board sensor switch.:

 

[Walz]

More photos:

Sensor switch, motor plug

 

[Walz]

More photos:

The complete clock movement with the circuit board attached to it.

 

[Walz]

Hello,

it is no rocket-science to put company and type ("Style:") into a search engine. You will find that HMI stands for H-type Minute Impulse Movement. And that alternating 24-V pulses are needed.
So this thing is an ordinary 24V slave movement. Pulses are the European style alternating type.

Slave controllers are offered in the web for far below $900 ...


Regards,
Frank

Frank, I am confused between slave and pulses, I thought it was the same language.

 

[harold bain]

Seems like a lot of electronics just to move a pair of hands. What else does it do??

 

[Walz]

Well, when I read up on the controller it does everything like keeping time via satellite, or something like that. I guess it can do a lot of useless things that I don't need. It has a battery backup when the power is restored the hands will move automatically to the correct time, it has a computer hookup, and it can be wired for several clocks together, like a 4 face clock.

I'm really in need of a basic clock movement to keep time and this is complicated however I will figure it out with some help. I really thought this was a regular clock movement and was I surprised to see the circuit board attached to the movement. Boy howdy.

 

[Tinker Dwight]

It isn't going to run with that driver board unless it has the
rest of the master clock.
I think if he'd like it to work, he's going to have to try to use
a transformer as we originally suggested. If it doesn't keep
accurate time that way, it would involve more than a simple fix.
A possible wheel ratio change might be possible but might still
be beyond what he is looking for.
Tinker Dwight

 

[Walz]

It isn't going to run with that driver board unless it has the
rest of the master clock.
I think if he'd like it to work, he's going to have to try to use
a transformer as we originally suggested. If it doesn't keep
accurate time that way, it would involve more than a simple fix.
A possible wheel ratio change might be possible but might still
be beyond what he is looking for.
Tinker Dwight

A ratio change would do the trick, would the motor assembly need changing? I'm up for any possible solutions to the problem. Any information is greatly appreciated by everyone just give some input and let see what's available.

 

[praezis]

Is there a circuit diagram of HMI-C8A available from electric time?
Would be very helpful.

I still suppose, this is a slave clock that moves by means of this ac motor instead of the usual stepper motor. Controlled by the photo sensor we can see on the photos. Needs 24V ac and 1-min pulse.

Frank

 

[Tinker Dwight]

Hi Frank
It seems you are right, although I don't think the board
uses a 24V AC pulse in. I think it uses a low voltage 1 minute pulse
and has a separate 24V AC continuous supply.
If you look at the board, you can see that it has a couple of solid state
relays on it to switch the 24V AC to the motor.
Tinker Dwight

 

[Tinker Dwight]

A ratio change would do the trick, would the motor assembly need changing? I'm up for any possible solutions to the problem. Any information is greatly appreciated by everyone just give some input and let see what's available.

It might work but we'd need to know the ratios it has now. If it worked out to an number
that matched motor that was available, it could be done.
Tinker Dwight

 

[flynwill]

There is someone who works at Electric Time who regularly posts to the tower-clock forum. Perhaps identifying him and sending him a PM might be in order.

Looking at the data sheet and instructions for their controller, I believe that what Walz has is a Minute Impulse movement, meaning it normally runs on a once-per-minute burst of 24V 60Hz. The datasheet for the movement says "8 - sec per minute" implying the movement expects a 8 second burst of 60 Hz. How accurate that 8-second burst has to be is hard to tell without testing. The controller is capable of fast-setting the clocks by running them at 6x normal speed. The wiring diagram clearly indicates three wires to the clocks "L1 L2 & C". So I would speculate that one of the "L" lines is to fast-run the clock or possibly there is "wait at the hour" mechanism of some sort. The black sensor in Watz's very first picture is a photo-interrupter sensor of some flavor, so I would speculate that is part of the electronic mechanism that advances the clock exactly one minute with each pulse.

I don't think any of the available hobbyist style slave clock drivers can provide this sort of one-per-minute AC pulse, but I could be wrong. I imagine that the Electric Time unit is beyond Watz's budget for this project. If I were doing it I'd probably use a small micro-computer (like the Raspberry Pi or Arduino), and small Audio amp capable of producing 24 VAC.

Watz's original plan of just replacing the motor for a slower one isn't out of the question. The motor looks to be like a pretty standard format. You would probably have to carefully count the gears in the gear train to know for sure what motor is needed. The motor he has is labeled "30 sec" which I would assume means 2 RPM. (Also means those 8-second minute advance pulses only move the motor a 1/4 turn more or less) So we can guess that the replacement would have to be more like 3-5 minutes per rotation. Whether such a motor is available or not I don't know. I did poke at the Saia-Burgess website, which re-directed me to Johnson Electric, but they asked that I "register" to get a datasheet so I stopped there.

 

[Walz]

There is someone who works at Electric Time who regularly posts to the tower-clock forum. Perhaps identifying him and sending him a PM might be in order.

Looking at the data sheet and instructions for their controller, I believe that what Walz has is a Minute Impulse movement, meaning it normally runs on a once-per-minute burst of 24V 60Hz. The datasheet for the movement says "8 - sec per minute" implying the movement expects a 8 second burst of 60 Hz. How accurate that 8-second burst has to be is hard to tell without testing. The controller is capable of fast-setting the clocks by running them at 6x normal speed. The wiring diagram clearly indicates three wires to the clocks "L1 L2 & C". So I would speculate that one of the "L" lines is to fast-run the clock or possibly there is "wait at the hour" mechanism of some sort. The black sensor in Watz's very first picture is a photo-interrupter sensor of some flavor, so I would speculate that is part of the electronic mechanism that advances the clock exactly one minute with each pulse.

I don't think any of the available hobbyist style slave clock drivers can provide this sort of one-per-minute AC pulse, but I could be wrong. I imagine that the Electric Time unit is beyond Walz's budget for this project. If I were doing it I'd probably use a small micro-computer (like the Raspberry Pi or Arduino), and small Audio amp capable of producing 24 VAC.

A $900.00 controller is way out of my budget for this project clock, I just want to hang it on the wall in my house and let it run. I don't need a clock that has all the fancy bells and whistles just set it and go.

If we can put something together that is functioning correctly and it's reliable that would be great. My concern is that I what to keep it as original as possible without changing the hands and movement. If someone else wants to be able to use it it would not be difficult to restore the movement back into a controller.

A Glo Dial clock is basic and easy, so why can't I have the same thing?

 

[Tinker Dwight]

Looking at the driver board and the number of connectors,
I suspect the driver board gets a continuous 24V AC. It uses
a separate logic signals to both advance the minute and
the fast run ( note the two solid state relays that can run
on a lower voltage than 24V ). I suspect that the optical
sensor is used to keep the motor from over running and that
the pulse width from the master is not all that critical.
Even if it does require 24V AC to drive it, a simple relay
added to the inexpensive master pulsers is not out of the question.
I believe it could easily be made to work fine for less then
$50.
Tinker Dwight

 

[flynwill]

You may well be right or possibly one of the "L" lines is continuous 24VAC and the other is the once/minute pulse. Back my suggestion of seeking help from the forum member who works for Electric Time and see if we can find out what sort of signal the clock wants.

Or go find a $20 battery/quartz movement that will fit the case and hands...

 

[Walz]

A $900.00 controller is way out of my budget for this project clock, I just want to hang it on the wall in my house and let it run. I don't need a clock that has all the fancy bells and whistles just set it and go.

If we can put something together that is functioning correctly and it's reliable that would be great. My concern is that I what to keep it as original as possible without changing the hands and movement. If someone else wants to be able to use it it would not be difficult to restore the movement back into a controller.

A Glo Dial clock is basic and easy, so why can't I have the same thing?

You may well be right or possibly one of the "L" lines is continuous 24VAC and the other is the once/minute pulse. Back my suggestion of seeking help from the forum member who works for Electric Time and see if we can find out what sort of signal the clock wants.

Or go find a $20 battery/quartz movement that will fit the case and hands...

As I said before, I want it as much original as I can, I'm willing to invest in this clock to run with the movement that it has, besides the hands are real heavy and a quartz movement would not budge the hands, even if you somehow attached the compression fitting on them. The size of the hour and minute hand are as big as pencils inside.

 

[Walz]

Looking at the driver board and the number of connectors,
I suspect the driver board gets a continuous 24V AC. It uses
a separate logic signals to both advance the minute and
the fast run ( note the two solid state relays that can run
on a lower voltage than 24V ). I suspect that the optical
sensor is used to keep the motor from over running and that
the pulse width from the master is not all that critical.
Even if it does require 24V AC to drive it, a simple relay
added to the inexpensive master pulsers is not out of the question.
I believe it could easily be made to work fine for less then
$50.
Tinker Dwight

How do I go about sourcing this item

 

[flynwill]

How do I go about sourcing this item

I would start by trying a PM to the forum user "Electrictime" and see if he can share any info about the signals needed to run the clock.

If you google "Slave clock driver" or "Slave clock impulser" will turn up some hits. I found one listed on EBay and Brian Mumford (www.bmumford.com) makes one. I would do some inquiries before purchase however as if the clock indeed needs a full 8 seconds of 24VAC that is quite a bit longer than the typical 1-2 second impulse. Brian Mumford's unit says the impulse duration on his unit can be set to any value between 0.1 & 1 second. But it's possible he could be persuaded to make a change to his microcode for a longer impulse.

To control the AC current from the impulser you would need a relay or solid-state relay. Something suitable can probably be found and most any of the online electronics suppliers: digikey, mouser, jameco, newark, etc.

 

[ElectricTime]

We do make a 115VAC friction set version of the same tower clock movement . The 24VAC movement is direct drive minute impulse - so if you run the motor continuously - it will run too fast - and if you get as lower speed direct drive motor - you wouldn't be able to set it. The movement runs on a alternating phase 24VAC signal. To run this on a cam - you would need a double throw micro-switch - mounted on a 1/2 RPM Synchronous 50/50 split cam. You can also generate this signal electronically - maybe with a timer or a PLC. There are two inputs to the movement - L1 and L2 - and a common - the signals are 24VAC - to run this electronically - you alternate every minute between L1 and L2. I would even think some European master clocks might provide this signal - my understanding the original design (though DC) -was to prevent a clock from advancing an additional minute due to contact bounce.

BTW - the computer running the board is really really slow - I feel like I'm on a dial up line.

 

[flynwill]

Oh that's way too simple ... So I would guess the "odd/even" switch I see on the board reverses the sense of L1 & L2, so that you can get clock in the correct phase of even vs odd minutes for the installation?

How long does each impulse need to be -- 8 seconds as we were guessing from the label?

Do bad things happen if the bursts are too long (or overlap)?

Watz -- If I were doing it I'd go the micro-controller route, but the cam on a motor route works too. I'm guessing from Thomas's comments about setting that these clocks do not have a slip clutch between the drive and the hands and so have to be set electrically.

I would suggest contacting Brian Mumford and see if he either has or can provide you with a version of his slave driver that instead of the typical 1 second on 59 seconds off output can do 1 minute on, 1 minute off, and the "fast set" mode set to do 10 seconds on and 10 seconds off. With that you could drive a double pole relay with the output and use that to switch the 24 VAC between L1 & L2.

If that fails there is such a thing as a "latching relay" were one pulse turns the relay on and another turns it off. But it may take some searching to find the correct thing (and you may still have the problem of the fast set mode being too fast for the mechanism.)

By the way, do you have the mate for the green connector "J1"? That looks like a "Pheonix Connector" the mate will have screw terminals to fit the wires into. If you don't have it they are readily available from electronics supply houses.