using a 16v supply to feed multiple needs

[pirouets]

I have not had much modelling mojo lately, but was pottering round the shed last night tidying up and looked at the number of transformers I have and started wondering

 

That transformer powers the controller. If the controller is not actually driving a train, can I also use the same 16v feed to supply the CDU as well? If the answer is yes, then I can get rid of some wires and a transformer, and stops me needing to buy a new transformer for my 2010 challenge layout.

 

The transformer is a gaugemaster M1.

[bertiedog]

I have not had much modelling mojo lately, but was pottering round the shed last night tidying up and looked at the number of transformers I have and started wondering

 

That transformer powers the controller. If the controller is not actually driving a train, can I also use the same 16v feed to supply the CDU as well? If the answer is yes, then I can get rid of some wires and a transformer, and stops me needing to buy a new transformer for my 2010 challenge layout.

 

The transformer is a gaugemaster M1.

 

If you are feeding a separate transformer to a 16 VAC controller it may not be a good idea to tap the 16 VAC for powering point motors.

 

Back EMF spikes occur when the power is removed from the point motor as it operates, and could interfere with the controller input even blowing the controller circuit, frankly unlikely, but possible.

 

 

Now, with a CDU this should not happen as most CDU designs suppress the spikes, but without checking a particular circuit it may best better to get another transformer, any 16 VAC will power a CDU, the maker should specify the current rating, but most would be OK with 1 to 1.5 amp or so, the CDU provides the current burst to operate the solenoids.

 

However......there is another very simple answer..... you could switch the power from the controller to the CDU, as if the points are operated when everything is stationary, the controller is not needed at that point. Use a double pole changeover switch and the problem disappears without a further purchase of a transformer.........

Hope this helps,

Stephen.