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[aaronjb]

I bought a gizmo the other day that arrived with a European two-pin power supply.. Ok, ok, I bought a toy for the kittens that came with a two-pin Euro PSU :oops:

It's driving a little water pump (it's one of those cat fountain things) and it's a 12V DC ~0.4A transformer (too big & heavy to be a switched mode PSU so I think it's just a transformer in a case), anyway the supplied UK adapter is about as useful as a chocolate teapot so it's currently rammed straight in the UK socket. Fine for me but I'd rather nobody else tried unplugging it and gave themselves a belt on the exposed metal as it comes out

Anyway.. given the driven load is a small motor (I'm guessing) is a switched mode PSU OK? I can pick one of those up with a 12V 0.5A output easily enough (e.g. http://www.maplin.co.uk/12vdc-0.5a-power-supply-with-2.1mm-tip-513515) - or does the nature of a switched mode PSU mean they can't drive motors for some reason..


Yes, the more time I spend writing this question the more it starts to sound like a stupid question... 

[Kevin Wood]

Can't see why a switched mode PSU wouldn't work, except that if the motor takes quite a big surge on switch-on the supply might go into current limiting or even shut itself down. Worth getting one a bit oversized for that reason, perhaps? Or get a good old-fashioned linear one, as it's hardly a critical application.

[Field Marshal Dr. Opti]

I bought a gizmo the other day that arrived with a European two-pin power supply.. Ok, ok, I bought a toy for the kittens that came with a two-pin Euro PSU :oops:

It's driving a little water pump (it's one of those cat fountain things) and it's a 12V DC ~0.4A transformer (too big & heavy to be a switched mode PSU so I think it's just a transformer in a case), anyway the supplied UK adapter is about as useful as a chocolate teapot so it's currently rammed straight in the UK socket. Fine for me but I'd rather nobody else tried unplugging it and gave themselves a belt on the exposed metal as it comes out

Anyway.. given the driven load is a small motor (I'm guessing) is a switched mode PSU OK? I can pick one of those up with a 12V 0.5A output easily enough (e.g. http://www.maplin.co.uk/12vdc-0.5a-power-supply-with-2.1mm-tip-513515) - or does the nature of a switched mode PSU mean they can't drive motors for some reason..


Yes, the more time I spend writing this question the more it starts to sound like a stupid question... 

Ah.....You're a big softy at heart, Aaron. 

I hope that Tiddles and co appreciate what you've done for them.

[Kevin Wood]

Ah.....You're a big softy at heart, Aaron. 

I hope that Tiddles and co appreciate what you've done for them.

They'll probably appreciate it as much as ours did the scratching post that is now completely ignored. "But.. thanks for getting me into this scratching malarkey. It's fun! and.... yep.. Works just as well on the sofas you've just spent a fortune having re-covered, too."

[Entwood]

cut the euro 2-pin plug off the cable and replace with UK 3 pin seems simple to me .... 

[Andy B]

Nige. The 2 pin 'plug' is molded into the back of the transformer- like your phone charger. That's how I understand!

[tigers_gonads]

Iphone / pods and various other bits and pieces come with a adapter that clips on.
Google and you might be lucky.

I have a old extension bank with a uk spec plug on the end of it which I keep for things like this 

Might be able to pull one ebay if you look around.
Better then pishing around with power supplies imo 

[sdwall]

Both Kev and TG are spot on. Make sure the switched mode PSU will have enough overhead to cope with surge to start or just get a european schuco type extension and fit UK plug on the end.

[tigers_gonads]

One of these 

http://www.ebay.com/itm/New-Universal-US-AU-EU-to-UK-3-Pin-Travel-Power-Converter-Adapter-Plug-/281138249265?pt=Travel_Adapters_Converters&hash=item4175253e31

[Entwood]

Nige. The 2 pin 'plug' is molded into the back of the transformer- like your phone charger. That's how I understand!

Makes sense now you say that ..

Easier ... and in £'s .. 

http://www.ebay.co.uk/itm/Schuko-Plug-Convertor-Euro-2-Pin-to-UK-3-Pin-Adapter-Ideal-Travel-Plug-Adaptor-/290690261204?pt=UK_Sound_Vision_Other&hash=item43ae7d60d4

[tigers_gonads]

Nige. The 2 pin 'plug' is molded into the back of the transformer- like your phone charger. That's how I understand!

Makes sense now you say that ..

Easier ... and in £'s .. 

http://www.ebay.co.uk/itm/Schuko-Plug-Convertor-Euro-2-Pin-to-UK-3-Pin-Adapter-Ideal-Travel-Plug-Adaptor-/290690261204?pt=UK_Sound_Vision_Other&hash=item43ae7d60d4

 

[aaronjb]

Or get a good old-fashioned linear one, as it's hardly a critical application.

They seem harder to find these days than switched mode supplies - although enough digging on the Maplin website did throw one up that doesn't say it's switched mode, so there is hope!   Ta though - I have a bunch of PSUs lying around from various things now defunct (like monitors) and one of those will probably fit the bill for free so it's worth a stab 

Ah.....You're a big softy at heart, Aaron. 

I hope that Tiddles and co appreciate what you've done for them.

I'll do anything for furballs They gained a whole bunch of new stuff yesterday - a ball constrained to a 'track' that flashes when they knock it around, a kind of face massage post thing, scratching post with beds, water fountain .. double sealed litter bin so the kitchen doesn't smell like cat crap anymore

Although they are still corralled into a makeshift 'room' we've built for them overnight - then again, we keep making the 'walls' higher and every morning they've either grown enough to jump over, or figured out what they need to push toward the wall to get a high enough vantage point to make it out Oddly enough they only start doing that when we get up - overnight they're happy to be contained with their beds, food, etc etc.

Easier ... and in £'s .. 

http://www.ebay.co.uk/itm/Schuko-Plug-Convertor-Euro-2-Pin-to-UK-3-Pin-Adapter-Ideal-Travel-Plug-Adaptor-/290690261204?pt=UK_Sound_Vision_Other&hash=item43ae7d60d4

That's basically what it was supplied with Only it's so appallingly badly manufactured that it only makes a good connection if you stand there holding it

Annoyingly my folks used to have a whole bunch of old German extension leads with UK plugs on the end from our time stationed in Germany .. right up until they moved house on Tuesday and threw all that kind of stuff out 

[Marks DTM Calib]

Its very dependent on the switchmode supply design.

Assuming the device being driven is a DC motor then at standstill the supply will see nothing other than the DC resistance of the stator and rotor. Its only when the thing starts to rotate and a back EMF is produced does the current drop and hence the start current can be very high and to the supply will appear as a very low ohmic load.

Many switchmodes wont like this high start current (some have crowbar current limit on the output), others will simply limit the current and be ok.

If going switchmode look to over rate it by a factor of 2 and all should be ok, I would actualy aim for one nearer to 1 amp.

Argos do one for about 13 quid:

http://www.argos.co.uk/static/Product/partNumber/9829701.htm

[aaronjb]

Cheers Mark - I'll pick something up at the weekend if I don't have something that'll work knocking about the garage somewhere 

Failing that it'll continue to work with the aid of a screwdriver in the earth pin and the German plug rammed into the other two  At least more reliably than using the cheap adapter they supplied with it!

[Marks DTM Calib]

No need to leave the screwdriver inserted in the earth pin (not that I have ever done that), its only needed to clear the shutters from the live plus neutral