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What size Potentiometer?

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The toggle switch option is an excellent idea.

PSU size, depends upon the total maximum load. If on average 250 mA is drawn, look for a 24V 500mA supply.

Best is to build one yourself with a transformer, bridge rectifier , good size capacitor 10000uf 63 Volts and fused in- and outputs.

The slaves on this board are the ones with the alternating polarity inputs?

They may need connecting to P and N terminals as those clocks require +24V-0 , -24V-0, +24V-0, -24V-0 and so on.

BTW did you put a series resistor on your test led's ? ( about 2k2 or 2k7).

Regards, Raymond
 
The toggle switch option is an excellent idea.

PSU size, depends upon the total maximum load. If on average 250 mA is drawn, look for a 24V 500mA supply.

Best is to build one yourself with a transformer, bridge rectifier , good size capacitor 10000uf 63 Volts and fused in- and outputs.

The slaves on this board are the ones with the alternating polarity inputs?

They may need connecting to P and N terminals as those clocks require +24V-0 , -24V-0, +24V-0, -24V-0 and so on.

BTW did you put a series resistor on your test led's ? ( about 2k2 or 2k7).

Regards, Raymond

Hi Ray
Yes I did put a series resistor on the LED'S!!! all tested fine and I tested with the AC. slaves!!!

If you take a look at my vid on the panel you will see that each batch of 5 transistors have P.N.+.-.4 terminals x 5 for each set. P and N are for the slaves +and- obviously are for the 24vdc and the 4 is from the master. 4 actually is positive all the time but my master sends a neg. on each contact this shorts out that line causing the transistors to polarity change!!!

My question with the 24v and thinking it's not enough is because on the panel (very bottom) we have the same terminals P,N,+,-,4 so obviously these terminals power the transistor terminals!!!! but I'm also told this is where the +24v goes in and this is the main supply to the whole unit!! and for me it's not enough.

I need an educated mind on it!!

I know that each of the 5 trany circuits require 24v alone so should I times this by 5 at the main supply?????????????????

your slaves on their way!!!!!!!!!!!!!!!!!!!

Cheers
 
Normally for a 12 or 24 Volts system all the clocks are in parrallel.

Just checked a FAVAG slave which draws 7 mA at 24 V. A Bürk slave draws about 9 mA.
clock coil R measured about 3.5 k.ohms.

What is the actual resistance of one Gents clock coil ?

You only need one PSU, You need to measure the total load drawn by all clocks and relays with an ammeter on the dc range.
Then allow for an extra 50 % margin on top of that if you want to add more clocks in the future.

Regards

Raymond
 
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Hi Ray

I will check the resistance of all the 12 slaves, I suspect they are 4ohm each at max 250ma Then there's 25 transistors and all the other components..

U = ( 0.25) * R (48) =12 Volts ? That's just for the 12 slave within the panel.

What about the 5 transistor circuits each need 24v to run? see attachment for circuit 5 circuits liker this in the panel (no1)

Not forgetting all of these have one supply terminal at the very bottom of the panel.

See other dwg. for how these are wired in.

Total V's to supply the whole unti?



Cheers
 

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Interesting hadn't seen the second drawing in our prvious correspondence.

That indicates that the seconds slave clocks are in parrallel.

I doubt it that those clocks are 4 Ohms and 250 mA ( definitely not on 24Volts )

I will have a close look at those drawings, hope they print out to full A 4 size.
 
Hi Mark, can you please email me the second drawing on as big size as possible please, pref. A4

My eyes aren't what they used to be so I can work the connection drawing it out.

Cheers

Raymond
 
Interesting hadn't seen the second drawing in our prvious correspondence.

That indicates that the seconds slave clocks are in parrallel.

I doubt it that those clocks are 4 Ohms and 250 mA ( definitely not on 24Volts )

I will have a close look at those drawings, hope they print out to full A 4 size.

Hi Ray

Measure resistance and it is indeed 4ohms max 250ma,
 

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Circuit analysis

Hi Mark,

I did manage to get the drawing bigger in paint, and work out a possible option as far it appears logic to me.

From the transistorised polarity changer:

Terminal 4 appears to be a control terminal from the Gents GPO and receives 30 seconds or 1 second impulses ( upper or lower schema )

The negative is connected to the negative of the 24V accumulator, direct for the seconds clocks and via the GPO for the 30 seconds clocks.

The positive is connected to the positive of the 24V accu, direct for the seconds clocks and via GPO for the 30 seconds clocks.

The P and N terminals are for the 24V slave clock string respectively

With your multiple clock controller which can control 10 independant clock strings of many slave clocks each, it looks that you have to jumper the terminals.

From left to right

1.--e.g. from master to the 4's
2.--negatives
3.--positives
4.--not jumpered and control one or two slaves for testing
5.--not jumpered and control one or two slaves for testing

Basically you can use one or two drivers to test matters out but can expand up to 10.

Ensure that the bipolar clocks are 24 Volts or at least have a 1 to 2 k.ohm coil value. Not 4 ohms which would yield in 6 Amps at 24 volts and probably burn someting out.

Hope it help,

Raymond
 
Just lost what I wrote up.

watching your photo on the laptop as my daughter needed the other computer to play games.

I think that the pilot dial needs to go in series with the parrallel slave clock line, hence the 150 - 220 mA current.

Try this

From P in series through the pilot dial and connect the other end, lets call it Q to the 24 Volts slave clocks
The return wire from the slaves goes to the N terminal.

With not enough loading on the output the pilot dial will not operate properly so for testing use a 24 V slave clock on the 24V output and fit a dummy resistor of 150 to 180 ohms.
It will yield in a current of 160 mA, enough to operate the pilot dial reliabily.

Hope that works

Cheers

Raymond
 
Post # 31

I concur that the whole system runs off 24 Volts.

Bear in mind that the dummy resistor needs to be 5 watts and will get hot

It dissipates nearly 4 Watts!!

24 / 150=160 mA

0.16sqrd x 150 = 3.84W
 
Just lost what I wrote up.

watching your photo on the laptop as my daughter needed the other computer to play games.

I think that the pilot dial needs to go in series with the parallel slave clock line, hence the 150 - 220 mA current.

Try this

From P in series through the pilot dial and connect the other end, lets call it Q to the 24 Volts slave clocks
The return wire from the slaves goes to the N terminal.

With not enough loading on the output the pilot dial will not operate properly so for testing use a 24 V slave clock on the 24V output and fit a dummy resistor of 150 to 180 ohms.
It will yield in a current of 160 mA, enough to operate the pilot dial reliabily.

Hope that works

Cheers

Raymond


Hi Ray

Not tried anything yet,,, as had to do other tasks, I got in trouble from her indoors!!!

But are you saying that the pilot slave within the panel won't run without enough load on the external Parelle circuit???? As you will see on the VID. that the external (Aux) have a +/- terminals 12 of each... So are you saying connect a 150-180ohm R to each of those parallel outputs to draw more load????????

Brain freeze!!!

Mark
 
Hi Mark,

That is the way I look at the schematic, which indicates that the external slave clocks are run in parrallel on 24Volts.

There is nothing mentioned about the pilot dial, although it is current operated at between 150 and 220 mA.

What is the actual resistance of the pilot dials coil ?

The dummy R needs to be connected on the same terminals as where the slave clocks go. ( P and N )

Regards, Raymond
 
Hi Mark,

That is the way I look at the schematic, which indicates that the external slave clocks are run in parrallel on 24Volts.

There is nothing mentioned about the pilot dial, although it is current operated at between 150 and 220 mA.

What is the actual resistance of the pilot dials coil ?

The dummy R needs to be connected on the same terminals as where the slave clocks go. ( P and N )

Regards, Raymond

Hi Ray
Sat with laptop on knee and just got your reply..I think that Mother Nature will eventually have a PC. introduced into the Human body!!

I can see that the external slave are to be in Parallel!!! The very bottom terminals slave outputs although marked +/- will in fact come from P/N

I was disappointed about the detail on the Schematic and the fact no pilot dials were drawn in and this is why I was left confused...... Not hard!!!


The pilot coils It seems to me are series value coils at 4ohms usually Parallel are much bigger??????

I have to get some 5watt R's probs tomorrow then I will do the tests putting them.

Another point!! sorry!

You will also see another question on the vid. I had was about the pilot slaves about why the terminals has screw in washers that could be added thus bridgeing the terminals on each slave!! this now I think explains the reason..as these are in series with the external slaves removing one would render that supply line dead!! so the washer effectively bridged the contacts so the supply could flow...... am I right?????

Cheers!!
 
That makes sense with the washer now, your conclusion is correct there.

That is for bridging out the whole string on the circuit concerned.

If you connected the 4 ohms pilot coil in parallel on 24 Volts would yield in 6 Amps! and possible smoke.

The schema is confusing as the pilot dial should have been drawn in.
 
That makes sense with the washer now, your conclusion is correct there.

That is for bridging out the whole string on the circuit concerned.

If you connected the 4 ohms pilot coil in parallel on 24 Volts would yield in 6 Amps! and possible smoke.

The schema is confusing as the pilot dial should have been drawn in.

Hi Ray

So for a novice could you explain why by adding 'load' to the very bottom terminals (p/n) would allow the series pilot slaves to work!!! why wouldn't it work without load????

Sounds promising, will get the resistors tomoz!!

Cheers!!
 
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