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Cobalt point motors - wiring for DC - further queries


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  • RMweb Gold

I would be very grateful if someone could direct me to a simple and easy-to-understand guide on how to wire up a single Cobalt point motor for conventional, DC control, incorporating 'frog' polarity switching.

 

I've looked at the PDF that you can download from Cobalt, and to be honest, I even find the bit on page 7 covering DC operation confusing.

 

Many thanks.

 

Edited by Captain Kernow
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  • RMweb Gold

I would be very grateful if someone could direct me to a simple and easy-to-understand guide on how to wire up a single Cobalt point motor for conventional, DC control, incorporating 'frog' polarity switching.

 

I've looked at the PDF that you can download from Cobalt, and to be honest, I even find the bit on page 7 covering DC operation confusing.

 

Many thanks.

 

Look at your Cobalt from the operating lever side.

Wires from your switch attach to the two outside contacts on the Cobalt contact switch.

Three addidional wires are needed if you wish to control frog polarity, and these connect to the second, third and fourth contacts from the left. The second contact goes to one outside rail of your point, the third goes to the other outside rail and the fourth goes to the point frog.

 

Will you be using a DPDT switch or a pair of momentary contact switches to operate your point?

Edited by Mick Bonwick
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  • RMweb Gold

Will you be using a DPDT switch or a pair of momentary contact switches to operate your point?

Thanks, Mick.

 

Not sure, to be honest. I thought they worked the same as Tortoises?

 

What would you recommend?

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The current CobaltClassic ( Omega ) , has

Pin1 ( next to the voltage select switch ) Motor ,

Pin2 :Motor

 Pin 3: Feedback ,

PIn4:Switch-L,

Pin5: Switch -R

Pin6: Switch Common 

Pin7: Switch Common 

Pin8: Switch-L

Pin9: Switch-R

 

I agree the "manual " is the greatest heap of rubbish Ive seen in a long time , to actually work out what the Feedback Pin is , I dismantled one and traced the circuit

 

Why they call the switches 2, 3 , what happened to switch 1 ???

 

Far too much wordy text with confusing explanations , pure junk 

Edited by Junctionmad
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  • RMweb Gold

Thanks, Mick.

 

Not sure, to be honest. I thought they worked the same as Tortoises?

 

What would you recommend?

 

I have used Tortoises on two layouts to date and never had a problem with any of them. One layout used DC and DPDT switches and the other uses Hare decoders, Digitrax control system and JMRI.

 

I have installed Cobalt on two layouts and had to return 2 of the 9 used as faulty. They were replaced without question. On both layouts they were controlled with DCC, but if DC had been chosen then my choice for operating them would be DPDT switches. A personal choice dictated by experience and simplicity of installation in conventional control (mimic) panels. It was all a matter of decisions based upon experience, cost and ease of installation and use.

 

Not everybody would have the same requirements or experiences, so there will be many solutions to your 'problem'. :scratchhead:

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There is possibly confusion because you don't say which type of Cobalt motor you have. The original "Cobalt Analog", as I remember, was wired the same as the Circuitron Tortoise. This has the motor connections at terminals 1 and 8, as described by Mick above. If yours are like this, the wiring diagram on the Circuitron website shoud be helpful.

The current "Cobalt Classic Omega" has a different wiring layout as shown in the DCC Concepts PDF. I think they mislabelled two of the terminals in the PDF as Switch 2 Left and Switch 2 Right when they should have been Switch 3 Left and Right respectively.

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There is possibly confusion because you don't say which type of Cobalt motor you have. The original "Cobalt Analog", as I remember, was wired the same as the Circuitron Tortoise. This has the motor connections at terminals 1 and 8, as described by Mick above. If yours are like this, the wiring diagram on the Circuitron website shoud be helpful.

The current "Cobalt Classic Omega" has a different wiring layout as shown in the DCC Concepts PDF. I think they mislabelled two of the terminals in the PDF as Switch 2 Left and Switch 2 Right when they should have been Switch 3 Left and Right respectively.

 

no. They are labelled correctly , if rather bizarrely 

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  • RMweb Premium

There is possibly confusion because you don't say which type of Cobalt motor you have. The original "Cobalt Analog", as I remember, was wired the same as the Circuitron Tortoise. This has the motor connections at terminals 1 and 8, as described by Mick above. If yours are like this, the wiring diagram on the Circuitron website shoud be helpful.

The current "Cobalt Classic Omega" has a different wiring layout as shown in the DCC Concepts PDF. I think they mislabelled two of the terminals in the PDF as Switch 2 Left and Switch 2 Right when they should have been Switch 3 Left and Right respectively.

 

The original Cobalt had 8 terminals and was similar in connection to a Tortoise (power feed on the two outer terminals)

 

The Cobalt Digital has the power in terminals at one end - again an 8 way terminal block.

 

The Cobalt Omega and Analog IP a have identical connections on a 9 way block - power in at one end.

 

The Cobalt Digital IP - power in at one end and also 9 terminals.

 

All Cobalts apart from the original one have the connections marked on the rear of the circuit board behind the terminal block.

 

Cheers,

Mick

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  • 3 weeks later...
  • RMweb Gold

My thanks to everyone who has helped with this, especially Mick for his off-line advice.

 

I now find that I need to find a '12v regulated DC supply' to power the Cobalts that I have.

 

Gaugemaster don't seem to do anything, unless the 12v is controlled by a knob on a traditional controller. Their sealed transformer units only appear to have 16v AC as an output.

 

Can I actually power these point motors from a traditional 12v DC controller, or do I need something that puts out a constant 12v supply?

 

Thanks.

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  • RMweb Premium

Some DC controllers have "dodgy" waveforms. 

 

Best option is a plug in wall supply. Key word is regulated.

I always used to point people in the direction of Maplins......

 

BTW, a Cobalt will quite happily work on 9v - all it does is run a bit slower.

 

 

 

Cheers,

MIck

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  • RMweb Gold

Best option is a plug in wall supply. Key word is regulated.

I always used to point people in the direction of Maplins......

 

 

 

Plenty of online place to try these days e.g.

 

https://www.rapidonline.com/catalogue/search?Query=12v%20power%20supply

 

Most interesting chaps, thanks.

 

So would a mobile phone charger work, one that also plugs into the wall?

 

Mick - you say 'used to'. Don't Maplins exist any more then?

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  • RMweb Premium

Most interesting chaps, thanks.

 

So would a mobile phone charger work, one that also plugs into the wall?

 

Mick - you say 'used to'. Don't Maplins exist any more then?

Maybe/probably? I have several 12V Regulated charger types but the ampage varies. I would suggest you only need 1 or 1.5 A and you can get them online for about £6. You can have one of my spare ones for £10 :triniti:  :angel:

Incredibly these particular pieces of trickert have actually worked when I fitted them!!!!!

If the plug is useless then just cut it off (leaving about 30mm of wire in case you need to use it elsewhere)  and lo you have two wires (brilliant for DCC of course) just right for DC.

Phil

Edited by Mallard60022
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  • RMweb Premium

Most interesting chaps, thanks.

 

So would a mobile phone charger work, one that also plugs into the wall?

 

Mick - you say 'used to'. Don't Maplins exist any more then?

 

Maplin went bust earlier this year.

Phone charger/plug in type is good.

 

How many motors are you going to use?

1A will power a lot of them

 

Plenty of power supplies out there for £5-£7 Amazon/ebay/Rapidonline for example.

 

Cheers,

Mick

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My thanks to everyone who has helped with this, especially Mick for his off-line advice.

 

I now find that I need to find a '12v regulated DC supply' to power the Cobalts that I have.

 

Gaugemaster don't seem to do anything, unless the 12v is controlled by a knob on a traditional controller. Their sealed transformer units only appear to have 16v AC as an output.

 

Can I actually power these point motors from a traditional 12v DC controller, or do I need something that puts out a constant 12v supply?

 

Thanks.

 

 

You may find 12V is a little too much juice for your Cobalts.  They seem to prefer something less - around 9V.

 

Old laptop power supplies have been suggested as a possible source.  

 

I picked up my "wall warts" from DCC Concepts as well, and - obviously - they are fine.

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  • RMweb Gold

Maplin went bust earlier this year.

Phone charger/plug in type is good.

 

How many motors are you going to use?

1A will power a lot of them

 

Plenty of power supplies out there for £5-£7 Amazon/ebay/Rapidonline for example.

 

Cheers,

Mick

Hi Mick,

 

I have a total of 6 on the layout but only plan to operate them one at a time (unless I link the two operating a run-round crossover).

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  • RMweb Premium

Hi Mick,

 

I have a total of 6 on the layout but only plan to operate them one at a time (unless I link the two operating a run-round crossover).

 

A 0.5A supply will be more than sufficient for 6 motors.

 

Cheers,

Mick

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  • RMweb Premium

Let's see if I have learnt something and then Mick and Co can give me a gold star or a big red cross.

I believe that a bit more ampage won't be a problem as the points only draw the power they require. Volts are important though. Therefore I think a 12 V regulated @ 1A would be OK and then you migh drive some other stuff from it?

Please sir is that about right?

Tom Brown.

Edited by Mallard60022
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  • RMweb Premium

Thanks Mick.

 

One other question, though - if I end up with a supply of greater than 0.5A (eg. 1.0A), would that harm the point motors?

 

What the Duck said...….

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  • RMweb Gold

Plenty of online place to try these days e.g.

 

https://www.rapidonline.com/catalogue/search?Query=12v%20power%20supply

So thinking about it, would this one be suitable, then, please? - https://www.rapidonline.com/powerpax-uk-sw3090-vi-15w-miniplug-top-psu-12v-dc-1-2amp-85-2902

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I extensively tested some cobalts , and dismantled and traced the circuit. Refer to the classic omega version only . Internally the voltage is clamped at arround 6.5V. so voltages over about 7.5 voltages in effect do nothing and just result in increased dissipation when stalled , at 12 V the stall current is close to 60mA which rapidly adds up where you have lots of motors in stall. It’s a very poor design from that point of view. Our current layout has 50 , and as a result we consume 2.5A doing in effect nothing

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