If I do it again ... forget the AMP and Volt Meters!

[kal]

Kal has a very specific reason for using separate power supplies for each meter, which made sense when I read it, but don't remember since it didn't apply to me.

See: http://www.theelectricbrewery.com/control-panel-part-2?page=9

Quote:

Because of the way this particular volt meter is designed (one of the AC inputs is tied to the DC ground), separate power supplies and transformers must be used in order to isolate the meters from each other. Trying to use one power supply and transformer to power both meters will destroy the meters (ask us how we know how!) even through the supplied instructions said this was possible.

Kal

 

[Rodrigoslr]

See: http://www.theelectricbrewery.com/control-panel-part-2?page=9

Quote:



Kal

Kal,

Ive read your instructions about using independent power supplies for each meter, but I was wondering if youve ever tried a converter to direct convert 220v ac to 5v dc, just like the one bellow. So that, we will use only one power supply (5v) to both meters.

http://www.ebay.ca/itm/AC-110V-220V...118816?hash=item5b17406020:g:~sMAAOSwT6pV1v8e

I know that you have the knowledge and hands on this subject, but dont you think that this could work?

 

[augiedoggy]

I know this thread is ancient and someone resurrrected it but Could it be that the stuff just isnt installed correctly in most of these cases due to the poor directions? If I had a nickel for ever time a thread popped up where the volt amp meter was assumed broken when in fact it was just wired wrong and fried by the time the op realized their mistake and rewired it...

I have bought about 5 different types of the cheap volt and amp meters for my panels I have built as well as about 8 of them for a solor power project and my experiences where good with them all except the 2 I fried by miswiring the shunts.

BTW these run off of the panel voltage and are super simple to wire up...
http://www.ebay.com/itm/LED-Digital...512884?hash=item20eb0df0f4:g:dWAAAOSw7NNT9ad5

 

[kal]

Kal,

Ive read your instructions about using independent power supplies for each meter, but I was wondering if youve ever tried a converter to direct convert 220v ac to 5v dc, just like the one bellow. So that, we will use only one power supply (5v) to both meters.

http://www.ebay.ca/itm/AC-110V-220V...118816?hash=item5b17406020:g:~sMAAOSwT6pV1v8e

I know that you have the knowledge and hands on this subject, but dont you think that this could work?

You posted this same question on my forum but I might as well answer here as well...

Yes, we used to use exactly something like that for our pre-built panels. Example:

We stopped because most required an internal board modification because of the way they were built. Most times you cannot just use them as is because of the non-isolated way the insides are wired - the same issue with sharing a single power supply/transformer with both meters. So I don't recommend them unless you have a good understanding of what sort of low level circuit board changes may be required and are willing to make those changes. Given that all brands are different detailed instructions can't be given so you have to have a good understanding of electronics to be able to reverse engineer the combined specific power supply you're looking at.

You'd still need to use separate supplies for the reasons previously stated.

Good luck!

Kal