# Vintage Simplex clock is it a Slave or Master + how do I convert it to a 240 volt power surply



## lenny123 (Oct 18, 2011)

Hello again some help required from some of you experts again

I have a 1960s 70s Wired Simplex wall clock which came from a old bus depot in Coventry
Now Ive done some research and it seems this clock is part of a network of Synchronous clocks
The question I need answering is is this a master or slave clock and what voltage runs it
if I wired it to my UK 240v mains would it run it or blow it :-s or do I need some sort of adapter

I have 6 of these clocks and would like to test them to see if they work or not but Im not sure how to
set them up if you have any info about these clocks you could help me and others out by sharing it ;-)

Thanks for taking the time to read my Thread
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## rationaltime (May 1, 2008)

Hi Lenny,

I don't know about these Simplex clocks, but I will make some
guesses.

First, you are showing us a slave clock.

I am surprised by what you are showing us. I think a clock
with a second hand would typically have a motor inside to 
drive the gears. The clutch would typically be used to 
synchronize the clock to the master clock. In your photos
I see no motor, and I see no wire to power a motor.

My guess is once or twice a minute a signal is sent via the
red and white wires to energize the solenoid and advance
the minute hand. In other words I think power alone can
not drive the clock. Only the sync pulses from the master
clock can do that.

I don't know how things are done in Merrye Olde, but around
here by code in a commercial building power wires must be run
in a conduit. I guess the building planners may not plan where
to install clocks. So the control signals would be low voltage
to avoid commercial wiring hassles. In this case I guess the
control signals would be 24V.

I would *not* hook anything to 240V mains power.

[edit: I did a little search. The signal may be based on 24V DC.]
Go read here:
Synchronizing Dad's Antique Impulse Clocks using LabVIEW FPGA
and here:
Turn antique slave dials into functioning clocks 

My suggestion is to get some batteries. Hook the batteries in series
to get 20V to 28V. Connect the negative side of one battery to the
white wire. Then touch the red wire momentarily for a few seconds
to the positive side of the battery at the other end of the series.
With any luck when the wire is touched the solenoid will click in and
advance the minute hand, then release when the connection is
broken. If not try reversing the white and red connections.

Good luck, and let us know if any of these guesses work.

Thanks,
rationaltime


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