point issues/cdu

[Scoobydoo]

Hi never had so many problems as getting points to work, well now have one working but I need to find a power supply for cdu, spoken to chap bought from as good as a paper bag on a wet day. I am lost with this as have no electrical idea, telling me to get 25-50va transformers, sounds easy, but needs 2a rating and needs to have vac 16-24, when you place this in to any search engine you get one of the answers not all three you need to know if item is correct, can any one advice on what I can but /purchase , name or product number, and will the run frm being plugged in to mains

 

cheers

[ianLMS]

He was probably referring to one of these mains powered transformers. Not sure what point motors you are trying to drive with the CDU but these should work fine for the Peco solenoid type. They are only 1a but should be sufficient and are recommended for point motor CDU's as well..

 

https://www.gaugemasterretail.com/magento/gaugemaster-gmc-m1-eu.html

 

or one of these if you are going to hide it within a panel;

https://www.buffersmodelrailways.com/gaugemaster-t1-open-transformer-output-2-x-16v-ac-1a

 

The other question is what controller are you using? Many of the analogue controllers had separate 16v AC outputs for accessories and this could be used for CDU's as well.

 

Ian

Edited May 20, 2020 by ianLMS

[crompton 33]

Phone this guy up . he will tell you what you need . Plus a lot cheaper then gaugemaster.  https://www.railwayscenics.com/electrical-and-electronics-c-20.html     

[Oldddudders]

A 2a transformer with a 24v output would be 48 va - or watts, as I believe they used to be called?

[Scoobydoo]

below is what im after, but its only a 1.25 amp, im needing 2amp, I keep buying all these things supposed to run that don't have what`s need to actually run them, to be honest im shocked of the shelf stuff is poor for what it is.

 

thanks for all your help

 

https://www.gaugemasterretail.com/magento/gaugemaster-gmc-m1-eu.html

 

or one of these if you are going to hide it within a panel;

https://www.buffersmodelrailways.com/gaugemaster-t1-open-transformer-output-2-x-16v-ac-1a

 

[Guest Half-full]

This chappie will sort you out....

 

https://connectec.uk/electrical/power-supplies-psu/desktop-power-supplies/haydon-24v-ac-ac-power-supply-transformer?variant_id=10837&gclid=CjwKCAjwqpP2BRBTEiwAfpiD-7kMMRYX5sF0xrpmcUVnF6v-o9QrXMej5NgFeaYjbxSro49Mk0hSjhoCKhcQAvD_BwE

 

[John ks]

A simple (I hope) explanation of VA (Volt Amps)

Power is calculate using P=I*V

Where P = power in Watts, I = Current in Amps & V = Volts

The A in VA refers to amps or current so I = A

If you substitute A for I in P=I*V you get P=A*V

Which looks as if Power = VA

In a DC circuit P does = VA but Power (in Watts) not VA is the term(usually) used in DC circuits

In an AC circuit Power only equals VA when the PF (Power Factor) equals 1

PF will equal 1 when the load is resistive

With an inductive or capacitive load, the PF will no longer be 1

The VA will no longer equal the power (in Watts) (after this it gets more complex & there so many formulas I’ve forgotten)

 

When selecting a power supply for model railways you need to know 5 things

1 is it safe. Approved for use in your country

2 is the primary voltage correct for your country

3 is the output AC or DC

4 what is the secondary voltage you need

5 what is the maximum current you are likely to draw

 

Scoobydoo was given 3 bits of information

1 A VA rating                     (not really needed as it can be calculated from VA=V*A)

2 a voltage i.e. 16-24VAC

3 a current of 2A                     (16V at 2A = 32VA & 24V at 2A = 48VA)

When you go searching you should only need the output voltage & current

 

Another consideration is do you want a transformer or a power supply

The difference is a transformer is one of the components in a power supply

John

 

Ps in your  2nd post the transformer is the second link can kill you if it is not installed properly

[Scoobydoo]

right have point working, moves for 5/6 times. then point will not move, 2 weeks and not got one point to work 100%

[Guest Half-full]

2 hours ago, Scoobydoo said:

right have point working, moves for 5/6 times. then point will not move, 2 weeks and not got one point to work 100%

Are you changing the point rapidly?  The CDU will quickly run out of charge if the motor is rapidly moved, and will need time to build that charge up again

[Oldddudders]

What sort of switch are you using to trigger the point motor? It must only be momentary, then off. 

[Scoobydoo]

right it can not be this hard 3rd week and still have no points working, 

peco solenoid points

powered up,

works one way only, using cdu, cdu make no difference, any one close to wgc to assist

points move freely by hand, pointe level, im frustraited some thing simple can or does not work

 

[Guest Half-full]

58 minutes ago, Scoobydoo said:

right it can not be this hard 3rd week and still have no points working, 

peco solenoid points

powered up,

works one way only, using cdu, cdu make no difference, any one close to wgc to assist

points move freely by hand, pointe level, im frustraited some thing simple can or does not work

 

If its moving in one direction but not the other the it seems the point motor isn't at a square 90 degrees to the point, even with a low amp supply the solenoid should work in the other direction. 

On 22/05/2020 at 13:46, Oldddudders said:

What sort of switch are you using to trigger the point motor? It must only be momentary, then off. 

As asked above, what type of switch are you using?  We would need that question answered to rule that out of the equation.  

 

[Suzie]

A few questions to try and isolate the problem:-

 

1. What power supply are you using for your CDU?
2. What size wiring are you using for the point motors and switches and from the CDU?
3. Which Peco motors do you have and how are they fitted?
4. Which switches are you using?

There is a lot you can get wrong with solenoids.

 

Suzie x

[doilum]

A cautionary tale from the previous century. Back in the day, one esteemed club member would build his own CDU. Coupled to the old school H&M solenoid point motors with ,16 volts they had a kick like a mule watered with Tequila. Life expectancy of a frequently used  Peco  OO point was a handful of shows........