Adaptor query.

Thanos

I need to get a new (or at least working) power adaptor. the spec in the instructions says
Adaptor Input: 230V - 50Hz 100mA
Adaptor Output: 4.5V DC 100mA 0.45VA

I have looked on ebay but can only see multi adaptors that say 4.5V but are 300mA

Can these be used or do you need exactly what it says (100mA)?

And if anybody knows where to get one that would be even better.
Thanks.

DublinDilbert

There is no issue using an adapter with a higher current rating than the device so from that point I'd view your grand.

The other thing you must look out for is if the output of the adapter is "regulated", ie does it always supply 4.5v or does this vary with the loading. Some equipment won't mind a variation in this, but other equipment will. So if you can get an adapter with a regulated output.

meercat

powercitys your man
think this should do the trick
http://www.powercity.ie/?par=25-90-A103WH

Peter Sweeney

Most electronic stores will sell adaptors suitable, maplins had a good selection

Bruthal

As dublindilbert said, the 300mA output of the ones you looked at will make no difference, once the voltage matches.

Some adaptors , especially 12v ones put out a higher no load voltage which comes down to 12v when they are loaded to their rated load, which is to do with what he suggested about regulated adaptors or power supplies, but a 4.5v adaptor with 300mA output rating should work fine for your 100mA item, or the item your 100mA adaptor powered.

Thanos

Thanks all for the replys, will pick up one of the 4.5V 300mA ones so....

Thanos

So i went out and bought one but now I do have one further question.
There are a number of different size pins to choose from, I am guessing I just select the one that best fits. However it then says you can set the polarity, how do i know which way to set it, positive or negitive???

Bruthal

Thanos wrote: »

So i went out and bought one but now I do have one further question.
There are a number of different size pins to choose from, I am guessing I just select the one that best fits. However it then says you can set the polarity, how do i know which way to set it, positive or negitive???

The old adaptor should have a marking on it showing polarity. It will show a sort of 3 quarter circle, and a centre pin inside that, and the polarity of each.

Most items are centre positive. The easiest way to tell is if you have a multimeter anyway. What is the adaptor powering?

Any link to the new adaptor you got?

Thanos

robbie7730 wrote: »

The old adaptor should have a marking on it showing polarity. It will show a sort of 3 quarter circle, and a centre pin inside that, and the polarity of each.

Most items are centre positive. The easiest way to tell is if you have a multimeter anyway. What is the adaptor powering?

Any link to the new adaptor you got?

The one i got was
http://www.powercity.ie/?par=25-90-A103WH

It is for an Electro Vita Circulation Massager

Thanks

DublinDilbert

Thanos wrote: »

The one i got was
http://www.powercity.ie/?par=25-90-A103WH

It is for an Electro Vita Circulation Massager

Thanks

Model : A103WH
Specifications
300ma Unregulated Power Supply
With 6 Interchangeable Tips
Gives 300ma From 3v-12v
Suitable For Personal Stereos
Radios
Portable Gaming Devices
& Toys


That's an unregulated adapter, which may or may not be an issue, depending on what its powering....

Bruthal

For a 4.5v item that had a 100mA adaptor, a 4.5v 300mA one should be ok though. Its voltage should be stable enough with 3 times the capacity of the original adaptor.