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Antique Clocks/Simplex Clocks


Hello Wayne,
 First, I want to commend you for volunteering your time to participate in this forum to help people learn about clocks. By doing so, you truly uphold the spirit of what some of the creators of the Internet wanted it to be used for - sharing information & knowledge - and I thank you!

I've got a few questions about some "Simplex" brand clocks I have acquired. I've got 5 or 6 large round ones and two large square ones.  None of them are equipped with standard power cords; although they are all equipped with ample wiring to attach to whatever they're designed for.  As well, the manufacturer thoughtfully adhered an electrical schematic on the back.  My question is this, Wayne:  can I attach standard power cords to these clocks and then plug them into a standard American wall outlet to make them work?  I'll provide the info below that is on the back of them regarding model numbers, voltage, etc.  I'm thinking that these clocks may have been an integral part of some sort of system, so I'm not sure if it would even be appropriate to attach power cords.  My hope is that you may know this.  Here's the info on the clocks:

On the back of the round one, the schematic label bears the diagram as well as this information:  Model 6310-9239.    In the top right corner there's a number framed by a box; I'm thinking it could perhaps be a drawing number? The number is: 804-053 H.   It also has other numbers on it:  
LR 5047  Listed Time Indicating Recording Equipment 5958.
At the bottom it says:  Simplex Time Recorder Co., Gardner, MA
The schematic indicates a Synchronous Motor, a Clutch Magnet, a Buzzer, and these electrical parameters:

115 Volts  4.6 V.A  60 Hertz
24 Volts  4.6 V.A. 60 Hertz
115 Volts  3.0  V.A.  60 Hertz
24  Volts  3.0  V.A.  60 Hertz
115 Volts 4.
V.A.  60 Hertz
 I just now noticed that there is a round large black dot to the right of "24 Volts, 4.6 V.A., 60 Hertz" for the motor, and to the right of the 24 volt, etc. for the clutch - perhaps, as if to indicate that the clock is set up for the 24 volts?  I can email you the photographs I took of the schematics if you want.
On the back of the square clock,  at the top of the schematic appears an identifying number - it says "Modified Type" and then the numbers 8145 have been stamped there.  At the top right-hand corner of this label appears numbers inside a box; they are:  804-007.  At the bottom it bears the manufacturer's information which is:  Simplex Time Recorder Co., Gardner, MASS, USA.  In the schematic, it refers to: "Syn Clock Motor", "Clutch Magnet", and leads, etc.  It identifies what appears to be an electrical plug that comes out at 115 Volts.  This clock does not have anything else about voltage on it, but it does have a chart with numbers in a column under the heading "FREQ".

Anyway, if you can tell from that info if I can attach a power cord and plug them in to see if they work; and if they are indeed part of a system, I'd appreciate it. Thank you, Wayne.

First of all, the numbers on the motor and clutch do not mean much as I have no books to tell me anything about the clocks.  That said, I think you may have some clocks that were in a school or factory.  If they are what I think they are, they were all connected together and the time was set daily by a master clock.  I have seen some of these in for repair but there is really nothing you can do if you do not have the master clock.  They have to work as a system.
Most of the time they were plugged in to 115V that ran the motor but once a day they were adjusted by the master clock through the 24V clutch system so they all showed the same time.
I am going to guess that the coil that drives the main clock motor is 115VAC and can be plugged into the wall plug.  This is only a guess.  The only way to be sure is to find someone with a variable power supply and start out at 24VAC.  See if the second hand moves.  If it does not increase the voltage until it will run.  I think you will find that it is around 100VAC.  This way you do not run the risk of burning anything out.

Before doing all of this, I would contact Simplex as they are still in business making time clocks and they may be able to help you.  Please let me know what you find out from them.

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I will answer any clock repair questions to the best of my ability but not appraisal questions.


I have been repairing mechanical and electric clocks for over 25 years.

I am a current expert in the small appliance catagory.

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