Off topic, anyone good at electronics?

Hello Peeps,

Two questions for the knowledgeable amongst you:

1. If I combine all the 12v outputs from a 450 watt ATX psu what sort of amps can I expect? Need to power a load of wiper motors and not sure how many I can squeeze out of each psu.

2. In order to get a full 12v from said ATX psu I need to also load the 5v output, an american web site says to use a 10 watt 10 ohm wire wound "sandbar" load resistor, can anyone confirm if H10R on this link is the right one?

http://www.maplin.co.uk/module.aspx?moduleno=2181

Thanks,

Ben

pretty sure you will need something beefier than a pc psu to power wiper motors (as they have massive torque)

Motor draw under load is about 8 amps at 12v (rising to about 14 if stalled), just a question of what proportion of the 450w is 12v.

Questionable maths, but I'd say in theory you could drive 3 motors off 35ish amps available. That's in theory. That's also alot of juice. You've not mentioned starting current, if they're all starting at once that might pop your psu.

Fuck it, give it a go. H10R looks fine for the 5V load.

Many thanks.

Reckon I might stick at two per psu thus hopefully giving myself a cushion.

450 watts....

so having 12v you should have 37. 5 amps ???

EDIT: using P = IV

atx psu power ratings are notoriously overspecced - 450w is probably closer to 300w real world and along with the fact that you have multiple voltage rails the actual output on the 12v rail is prob around 10A - so possibly doable but I would be inclined not to if as you say there is any chance the motor will stall - but bear in mind IANAEE

but bear in mind IANAEE

Excuse my dumb, but what does that mean? I ordered 13 x 450W today, I'll see how they run, I can always go one per psu if needed.

i am not an electrical engineer :)

Multigrooves has a E.E degree I think

Hmmmmmm

Buggerdoubledoo.

So I've converted a psu as per here:

http://web2.murraystate.edu/andy.batts/ps/powersupply.htm

It will run a wiper motor set up as I'll need it, however if I try to have two starting at the saem time they both stall. Stagger the start up and both will run (although the 2nd is just sitting on the bench with no mechanism attached so minimal load), guess I'm on one per motor.

Sigh.

1. Is this something I could connect a phone to, ie a BT line thingie?
   

2. Is this the thing I'd be connecting a sky box to?

yes and yes. But they look old, replace them when you sign up to a new phone/tinternet they should do it anyway free. unless it's BT who charge.

I'm moving everything so it's probably not going to be free. :S
BT is fucking shit.. when is google running fibre straight to my door so I can fuck these fools off?

I haven't got a bad word to say about Virgin TV, Phone and internet, really responsive and reliable and free fitting with everything you need to from the get go.

All those gubbins up there ^ was fitted at my place for free by one of their engineers, and pleasant fella he was too.

£25 a month. Can't complain.

Is that damp/scum/next weeks breakfast growing in the corners, did you have a full and proper survey done on the flat?

No, I decided to try something different and grout the walls with self-saucing chocolate pudding.