Orpington Astronomical Society

Astronomy => Technical => Topic started by: JonH on Oct 11, 2012, 22:35:59

Title: Power supply issues!
Post by: JonH on Oct 11, 2012, 22:35:59
After spending pretty much all of this evening turning a PC power supply into a power simply for my mount, dew heaters etc I plugged it into the mount for a test and turned it all on.
Sure enough it worked except the power light on my NEQ6 was flashing which apparently means it's not getting enough juice.
This is despite the power supply being 500w and according to the label can give me 18A on the 12v lines!
Needless to say I'm less than impressed!  :!

Anyone got any ideas?
Title: Re: Power supply issues!
Post by: Mike on Oct 11, 2012, 22:38:22
I would ignore it. Mine does this sometimes with a 6A supply and it works fine.
Title: Re: Power supply issues!
Post by: JonH on Oct 11, 2012, 22:46:20
But it doesn't make any sense, at 18A it should have everything it needs and then some!
Title: Re: Power supply issues!
Post by: Rocket Pooch on Oct 11, 2012, 22:57:51
Jon,

I used to have this till I upgraded the cable to the mount to a thicker cable, then its been fine ever since.

Chris


P.S. Still used to work ok with it flashing.
Title: Re: Power supply issues!
Post by: JonH on Oct 11, 2012, 23:05:25
That might explain it then, the wires to the mount are pretty hefty but the wires on the power supply are VERY thin! So much so I almost decided to use a 350w one I have kicking about simply because I wondered if they were up to the job. I guess this might just answer that question.
Title: Re: Power supply issues!
Post by: The Thing on Oct 12, 2012, 07:54:11
I found the fit of the mount power jack made all the difference. Also on the power supply, bunch the output cables and connect them all to all your twelve volt feeds to get round the thin write issue. Same with the grounds, equal bunches of each for each voltage.
Title: Re: Power supply issues!
Post by: JonH on Oct 12, 2012, 10:10:07
Doubling up the wires might be a way forward untill I can come up with a perminant solution as there are a few spare anyway. That or opening up the power supply and soldering the mount cable directly onto the 12v output!
Title: Re: Power supply issues!
Post by: The Thing on Oct 12, 2012, 10:37:57
I have all the twelve volt wires bunched and the same number of grounds to provide the twelve volt feed to my distribution block (old mini mains unit for hifis etc). Also you were going to use phono plugs, they are designed for milliamps in hifi systems, I did voice my reservations at the C&H on Tuesday...
Title: Re: Power supply issues!
Post by: JonH on Oct 12, 2012, 11:11:27
I didn't use the phono sockets in the end after thinking about it, plus they were not very good quality and proved more hassle than it was worth to solder.
Title: Re: Power supply issues!
Post by: JonH on Oct 12, 2012, 11:47:23
Right that's it, that pc power supply is going in the bin! I don't care if it's 500w!!
Just opened it up to see how hard it would be to solder everything into it direct, turns out although it has 5 12v outputs they are all split off one wire inside the power supply which is only 18awg!!!!  :o
Plus it looks like the bored inside it hasn't been screwed down properly is bent and has a crack half way threw the middle!