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View Full Version : 230v to 120v transformer dead, no idea why.


Sam__
01-31-08, 10:28 AM
Hey all.
First off I bought my pump off the classies a while ago and iv just got all the parts to put together a WCing system.
Sadly I completely forgot about the American plug and voltage difference (I was having a bad day alright,lol).
So I bought a transformer off ebay. Rated at 45W and the pump being 28W I though it should be perfectly fine.
So I got it in the post the other day and plugged it all in and it looked fine until after about an hour and the pump just shut off. So I flicked the switch a few times and nothing. :( not good. So I contacted the seller and they very kindly sent me another without me having to send the broken one back.:D
So I got the new one in the post yesterday and plugged it in and again it died after about an hour.
Both got very hot before they died. I was using one of those wind in extension cords but thats rated for over 1000W wound and unwound so im pretty sure its not that.

Any help would be mucho appreciated thanks.

Sam__
01-31-08, 12:11 PM
Could it have anything to do with the transformer not having a ground ?? the pump has the pin for ground but the transformer just has a plastic one.

JamesXP
01-31-08, 01:34 PM
Cheap and not capable of giving 28w?

Sam__
01-31-08, 01:38 PM
Cheap and not capable of giving 28w?

could well be...iv asked for a refund so I'll see if i can get a better quality one.

Sam__
02-02-08, 06:26 AM
Could it be anything to do with the transformer outputting at 50Hz and the pump needing 60Hz?? I think it is but I need to make sure.

Super Nade
02-02-08, 09:20 AM
Not a chance. The transformer has no control over the frequency. The ratio of turns controls the voltage ratio. It is a passive device.

What do you mean by "dead" ? Did it flame out?

Sam__
02-02-08, 12:20 PM
Not a chance. The transformer has no control over the frequency. The ratio of turns controls the voltage ratio. It is a passive device.

What do you mean by "dead" ? Did it flame out?

no flames they just stopped giving any power. The pump just shut off. Exactly the same amount of time for each transformer.

Super Nade
02-02-08, 12:51 PM
Is the transformer working? You can always hook it up to the mains and see if the step down has been accomplished by using a DMM (AC Voltage setting). Be very careful though, working with line voltage without proper insulation can be dangerous.

Sam__
02-02-08, 01:22 PM
Is the transformer working? You can always hook it up to the mains and see if the step down has been accomplished by using a DMM (AC Voltage setting). Be very careful though, working with line voltage without proper insulation can be dangerous.

im pretty sure neither of them are working cos the pump still worked after the first broke and im hoping the same thing happened to the second one so the pump is still working.

Super Nade
02-02-08, 04:56 PM
That does not answer the question about the transformer itself or why it failed. :)

Sam__
02-02-08, 05:31 PM
That does not answer the question about the transformer itself or why it failed. :)

I'll test it with a multimeter as soon as i can which should be 2moz.

Hipcrostino
02-03-08, 03:13 AM
the tranformers getting very hot before dieing dosn't sound good. They probably can't handle the load. What is the rated AMPage on them, and the pump?

Sam__
02-03-08, 03:53 AM
the tranformers getting very hot before dieing dosn't sound good. They probably can't handle the load. What is the rated AMPage on them, and the pump?

they are both rated at 45W and the pump is 28W, so thats 0.4A for the trans and 0.24A for the pump (running at 115V). Is there any way I could replace or upgrade any of the parts in them to make them work again? I might open one up this afternoon.

Sam__
02-03-08, 09:16 AM
I just opened one up and all that was inside was a coil....guess I cant repair that.

is this a posibility?
http://www.ocforums.com/showthread.php?t=546207

JCLW
02-06-08, 03:22 PM
http://www.maplin.co.uk/Search.aspx?criteria=VR05F&DOY=6m2

Sam__
02-06-08, 03:27 PM
http://www.maplin.co.uk/Search.aspx?criteria=VR05F&DOY=6m2

U seen the price tag on that baby.

JCLW
02-06-08, 07:42 PM
I'm sure you can find cheaper ones around at electronic surplus places.

All you need is a 2:1 transformer, I'd look for 100VA (~100W) or more. It sounds like the other ones are overloaded. If you have a clamp meter you could measure the current on both the high and low sides of the transformer and know for sure.

Do you have links for the pump and the transformer?

If it allows you to plug in a grounded appliance but only has a plastic ground pin itself then it is most certainly illegal, and potentially dangerous.