One for the electricians

[langy]

i want to put in a 12v power scource just to test stuff and been given this transformer, can some one tell me which connections to use, thanks

 

[rikrobson]

the L is live and the 4 Ns are to change the output. its set for 12V

the larger pair are the output as it states. They'll be 12V AC with a Max of 25A

 

[MrFluffy]

Not a electrician, but think you need to say if you want 12v dc or 12v ac, as that looks like a tapped transformer that will give you ac unless it also rectifies it after transforming it, which I doubt from looking at the labelling.

edit rik posted while I was typing but still posting as it makes clear the distinction between ac and dc output.

 

[richie00boy]

I'm guessing you want 12V DC. You will need a bridge rectifier and quite a large capacitor for that. Might be easier and cheaper to use an old PC power supply, that would be regulated as well.

 

[langy]

the L is live and the 4 Ns are to change the output. its set for 12V

the larger pair are the output as it states. They'll be 12V AC with a Max of 25A

Ah so it's 12v AC only

 

[langy]

I'm guessing you want 12V DC. You will need a bridge rectifier and quite a large capacitor for that. Might be easier and cheaper to use an old PC power supply, that would be regulated as well.

Yes mate 12v DC

 

[Robotstar5]

Have a look on the bay for a cheap CB power supply?.

 

[BrokenBiker]

It's wired correctly for 12v AC at the moment...either get a rectifier circuit on the thicker tails then tap off that or may be easier to just get a 12v DC supply

 

[MrFluffy]

If you find a upmarket cb psu, or a cheap lab psu, they will have a automatic crowbar, that is if you hang a load on them with a short or excessive draw, a protection circuit will kick in that wont require a manual reset once removed. Lab psu's let you adjust the limit the crowbar comes in, so say you expect a device to take 2amp and it takes 8 and starts smoking on a 10amp psu, you can set the current limit to come in at 2.5amp and note its drawing too much current often without creating enough heat to destroy it, also bump volts up to 13.8v if variable voltage to see how something responds to alternator charging voltage instead of 12v. Also see how it behaves with low voltage, Ive seen ecu's reset when under voltaged, and during cranking the system voltage in a car is reduced as you know.

Depends how much you will use it and what for and amps required if you can justify a cheaper lab psu though. This is the sort of thing I mean, but Ive seen them cheaper than this. http://www.ebay.co.uk/itm/NEW-DIGIT...00W-CV-CC-LAB-USE-HAM-CB-RADIO-/282176181180?

 

[Windy Miller]

I you don't mind a little faffing about, I can get you a power supply from a PC that makes a nice workshop power unit for testing stuff. What sort of curt would you be wanting to draw? FOC of course!

 

[Ton-up]

Can't you use a small 12v battery?

 

[langy]

I you don't mind a little faffing about, I can get you a power supply from a PC that makes a nice workshop power unit for testing stuff. What sort of curt would you be wanting to draw? FOC of course!

Thanks mate, it's only for testing things like wiring looms, wiper motors, fuel pumps, etc etc

 

[langy]

Can't you use a small 12v battery?

I don't really want a battery hanging around where I'm grinding and welding if you get my drift

 

[langy]

If you find a upmarket cb psu, or a cheap lab psu, they will have a automatic crowbar, that is if you hang a load on them with a short or excessive draw, a protection circuit will kick in that wont require a manual reset once removed. Lab psu's let you adjust the limit the crowbar comes in, so say you expect a device to take 2amp and it takes 8 and starts smoking on a 10amp psu, you can set the current limit to come in at 2.5amp and note its drawing too much current often without creating enough heat to destroy it, also bump volts up to 13.8v if variable voltage to see how something responds to alternator charging voltage instead of 12v. Also see how it behaves with low voltage, Ive seen ecu's reset when under voltaged, and during cranking the system voltage in a car is reduced as you know.

Depends how much you will use it and what for and amps required if you can justify a cheaper lab psu though. This is the sort of thing I mean, but Ive seen them cheaper than this. http://www.ebay.co.uk/itm/NEW-DIGIT...00W-CV-CC-LAB-USE-HAM-CB-RADIO-/282176181180?

Thanks fluff

 

[EddyP]

Depending how big a load you're planning to put on it. old computer PSUs are a cheap way to get a 12V supply, I have one that I've used for testing loads of things and it works perfectly, also cost me nothing as I took it out of an old PC before I scrapped it.

 

[Windy Miller]

Thanks mate, it's only for testing things like wiring looms, wiper motors, fuel pumps, etc etc

I'm not back in the office till Wednesday, but I'll see what I can do. I may be able to get you a server power supply - much higher current.

Watch this space!

 

[langy]

Depending how big a load you're planning to put on it. old computer PSUs are a cheap way to get a 12V supply, I have one that I've used for testing loads of things and it works perfectly, also cost me nothing as I took it out of an old PC before I scrapped it.

I tried a PSU but not enough power.

 

[langy]

I'm not back in the office till Wednesday, but I'll see what I can do. I may be able to get you a server power supply - much higher current.

Watch this space!

Thanks buddy, beer tokens waiting

 

[Windy Miller]

No beer tokens required Steve! Freebies!

 

[armalites]

Many battery chargers has a supply mode these days that you can use for such stuff.

I've got dozens of 12v 7ah sealed batteries which would be ideal but i doubt it would be worth the postage costs.