Paullampit Paull
Hiya 

I have the ad-8fx connected to  2 pairs of cobalts configured as one ip analogue and one classic in each pair - they work fine on a scissor crossing

i have connected another single original classic and when I throw the point there is a significant delay and then it moves slowly- it’s as though there is barely enough power to move the point 

today there is no movement at all

checked with 9v power supply attached directly to the cobalt and it works fine

 reattached the supply to a different output on the decoder - re addressed it and there is again no movement

i am operating NCE power pro and train controller I have 48 original cobalts and they all seem to work ok but through ls150 - I have seen ref to changing voltage range but there is no option that I can see to do this on the original cobalts

any ideas

cheers
Paull
n gauge British transition gwr
Quote 0 0
AHJAY
HI

OK, so the motor is fine but power is not getting to it.

If some work well but not others added later, its usually am atter of power delivery - either wire is too light or there is a suspect joint somewhere.

You should therefore suspect the power delivery to the AD decoder or between decoder and cobalt. How long are the wires? / What weight are the wires?

regards, Ahjay
Quote 0 0
Paullampit Paull
Hi Ahjay
have done the following
changed wire to 0.5mm sq multi strand - much thicker than the existing which drives the linked pairs succesfully - length of wire 80cms which is shorter than the ones that work successfully 
with a multimeter I have 15.3 v ac at the track
l also have 15.3 v ac input to the decoder
on the working points at the decoder I have 7.3 v dc output to the points from the decoder on switching 
on the single cobalt that won’t work it is also showing 7.3 v dc at the decoder and at the ends of the wires that go into the decoder 
no movement at the cobalt

took the output wires and put into a spare classic cobalt off layout works ok
put a mains supply with 12v dc directly to the non working cobalt - works fine
the only conclusion  I can draw is that this particular classic cobalt requires more than 7.3 v dc to drive it as it works fine at 12 v dc

this will mean swopping  it out for a replacement which is a real pain as Murphy law dictates that it is the most inaccessible point on the layout

unless you have any other suggestions

cheers 
Paull
n gauge British transition gwr
Quote 0 0
Paullampit Paull
Sorry should read the single cobalt that won’t work it is also showing 7.3 v dc at the decoder and at the ends of the wires that go into the cobalt
Paull
n gauge British transition gwr
Quote 0 0
AHJAY
OK, possibly.... but it will not be electronics that needs the higher boltage - it must be stiff for some reason.

I wonder - if that motor has not been used for a very long time the lubricant may have hardened. Try changing it a few times with a bit more voltage and it may free up. With a little caution, you could also spray into the slot with some form of aerosol lubricant which may also loosen things up.

regards, Ahjay
Quote 0 0
Paullampit Paull
Eureka!!!!- well done Ahjay - amazing what a squirt of wd40 will do - I know people don’t like wd40 near layouts but it was the only spray lubricant I had - thanks for your advice and I will keep an eye on the other 48 I have which were first installed nearly 9 years ago 

the reason I appear to be taking up so much of your time is that we moved house which meant dismantling chunks of the layout and then when I was re constituting I couldn’t remember a lot of the wiring issues I learnt originally - my advice to anyone is document everything you do especially the technicalities and even the basics like which colour wires you used for which application 

anyway this forum and the tech support on the tel has been fantastic in getting me back up running and in itself means I will look to you first when purchasing - good customer service needs to be rewarded nowadays

regards 
Paull
n gauge British transition gwr
Quote 1 0
AHJAY
That is great...

You are very welcome Paull... Nothing makes us all happier than a good result.

kind regards, Ahjay
Quote 0 0