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Old 08-01-2018, 04:13 PM   #11
Flashbang
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Just to try and help you further John....
What wire are you using from the CDU to switches or levers and out to the motors and back as the return? 16/0.2mm is the minimum.

What switches or levers are being used? These MUST be passing contact levers or sprung to centre Off type of switches (On)-Off-(On) type. If you used any switch that allows the power to remain On the CDU can't recharge and you run a risk when operating on straight AC or DC power (No CDU) of quickly burning out the motors coils! Solenoid point motor MUST only ever have a momentary pulse of power applied to their coils - around 0.5 seconds is more than enough!

Wire insulation colours vary make to make. e.g. Peco and Gaugemaster PM20 use Red and Black as the operation pair and Green as the return, while Hornby use Red and Green, as the two feeds and Black as the return. You need to ensure you have the correct wiring or they wont work correctly.

Finally, when a CDU is used, do allow a second or two between each lever or switch operation for the CDU to fully recharge. Operating a lever over and back quickly wont allow the CDU to recharge fully, so best is to move a point then wait 2 seconds before operating any other lever or returning the same one.
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Old 09-01-2018, 09:17 AM   #12
John Disdle
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Thank you all for your replies.
Motors are Peco PL11. They work ok when not connected to the point. Alignment is no problem, and there is no friction.
The CDU output voltage is 8.8 volts, which seems a bit low, and it is takes a few seconds to re charge. The earth return wire, is 10Amp mains cable, the point motor wire is from Track Shack, and thicker than the wire from the motors.
I am changing the CDU on Thursday for something better, and I have one O/C point motor to change as well.
The switches are center off, but I am changing to a stud and wand system, which will look neater.
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Old 09-01-2018, 11:59 AM   #13
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Hi
Wondering whether you incorrectly measured the CDUs output by using AC voltage range? It will be outputting DC. Even though the input might be AC.
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Old 09-01-2018, 01:23 PM   #14
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Hi Flashbang.

Measured as DC at the o/p of the CDU.
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Old 09-01-2018, 01:47 PM   #15
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Quote:
Originally Posted by John Disdle View Post
Hi Flashbang.
Measured as DC at the o/p of the CDU.
8.8 volts DC is far to low. I would roughly expect to see 1.4 times the input AC volts. e.g. 16v AC measured at the input expect to see 22 ish volts DC at the output when the output is open circuit.
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Old 09-01-2018, 02:26 PM   #16
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Thanks Flashbang.
That has to be the problem, so I will get that sorted Thursday.
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Old 09-01-2018, 08:25 PM   #17
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Thanks Hound Dog. It wan`t as difficult as I thought, but a screw terminal is still better.

The uncouplers do not work, they may have been secondhand. I have taken one apart, and bent the spring, but still no joy. So probably a bad idea.

The point motor actuators move freely by hand, work when activated unconnected to the point, but when connected, do not move the point. I have tried disconnecting the CDU, and using 12 volt DC which works, but still does not move the point. The motors were secondhand. Any ideas anyone please. I am getting disillusioned with things that should work, but don`t.
As suggested by others use 16v ac rather than 12 v dc .......although recommended by Peco in their CDU instructions I found my point motors unreliable with dc but work perfectly every time with ac supply.
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Old 10-01-2018, 09:07 AM   #18
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Thanks Hound Dog.

I have a 16 volt transformer somewhere, but so far not able to locate it. Probably in a safe place, if only I could remember....
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Old 13-01-2018, 09:11 PM   #19
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The transformer seems to have gone the way of the Dodo. Shame, because the Gaugemaster CDU needs AC only. So now awaiting a delivery.
The O/C point motor was changed for a new one, and I have spent some time fitting a mains switch, and wiring up. Trains should be running tomorrow….
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