Extractot fan dead, centre light working, DC voltage shows 0

[sparkless42]

I have an ageing extractor fan above a shower that goes into the loft. It has a two pin centre bulb which only comes on when the extractor is switched on. That continues to work. I thought I'd use a multimeter to check the DC power output in the transformer in the loft and can't work out why it always shows 0v. The meter is working - it measure the main voltage (as 330V which I understand to be correct) and I can test AA batteries with it ok. I plan on just changing the unit anyway but though I'd ask a) what am I doing wrong or b) could the transformer be at fault? Thanks

 

[DetlefSchmitz]

Are you sure it's dc?

 

[EFLImpudence]

it measure the main voltage (as 330V which I understand to be correct)

 

[CBW]

Make and model of components?

 

[sparkless42]

It might be related to this thread which has just shown up as a similar thread.

Measuring transformer voltage

Hi, I am having some problems with low voltage downlights and am trying to check if transformers are working. I have a digital multimeter that is recording 240v input but between 0-2v output, but should this be 12v. I have measured transformers that i know are working and i still get this...

www.diynot.com

Photo of the transformer attached - looks DC to me

 

[CBW]

It might be related to this thread which has just shown up as a similar thread.

Measuring transformer voltage

Hi, I am having some problems with low voltage downlights and am trying to check if transformers are working. I have a digital multimeter that is recording 240v input but between 0-2v output, but should this be 12v. I have measured transformers that i know are working and i still get this...

www.diynot.com

Photo of the transformer attached - looks DC to me

Looks like mains 230vac imo with 12v step down transformer for the lighting. No mention of 330v anywhere.

 

[DetlefSchmitz]

Photo of the transformer attached - looks DC to me

Doesn't say dc anywhere. Try to measure as ac. I suspect if it were dc it would also be marked + and -.

 

[flameport]

Photo of the transformer attached - looks DC to me

It's either busted, or it doesn't output anything until a suitable load is connected.
Given it's age, busted is most likely.

Either way, it's years past the time to sling that and the halogen lamp away and fit an LED instead.

If you want to keep the existing fitting, then a LED lamp and suitable LED driver will be required.

 

[sparkless42]

Thanks everybody. It's definitely AC then. I\m looking at this replacement:

HiB Turbo Cool White LED Illuminated Inline Chrome Ceiling Fan

HiB Turbo Cool White LED Illuminated Inline Chrome Ceiling Fan. Stylish Extractor Fan with Adjustable Timer & 2 Year Guarantee. Free Delivery Over £500*

www.drench.co.uk

It seems to be high quality. I just need the unit though and not the fixing kit. And it doesn't say what the power supply is. Chatting to their support but they are unable to help! I think it's 240V so I need to check the circuit is on the RCD