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Posted By: ColonialBld 12VAC - 06/04/04 02:17 AM
Have a Problem that I need some input on. I have 12 Coach lights which light up my landscaping that I run off of a 12VAC, 60hz, 2.5 amp, 300 watts Transformer. I have 3 lines running from this transformer and i am pushing approximately 240 watts. I did all this for my wife who has terminal cancer. I built her some custom fountains for the lawn which I order some low voltage pumps for. They are rated at 12VAC, 0.300 amps, 2.5 watts. Unfortunately these pumps will not run from my transformer. I thought it might be the pumps and the company sent 2 new ones in and they did not work. They do not sell a outdoor transformer to run these pumps. So can anyone tell me how I can take One line and drop down the amperage to make these pumps work. I would really appreciate any input in this matter because I would like to have them running when I bring her home from the Hospital. Thank you for your time.

Bill
Posted By: NJwirenut Re: 12VAC - 06/04/04 02:24 AM
You don't need to "drop down the amperage", as the motors will only draw as much current as they need from the transformer. What do the pumps do when connected? Nothing? Run slowly? Just sit and hum?

Have you measured the voltage at the motor terminals when it is connected? Are you sure that the pumps are designed for 12VAC power, and not 12VDC?

[This message has been edited by NJwirenut (edited 06-03-2004).]
Posted By: pauluk Re: 12VAC - 06/04/04 04:03 PM
Are you sure the pumps are designed for an AC supply? The majority of low-voltage fountain pumps of this type are DC motors.

The pump rating of only 0.3A also sounds rather low, and wouldn't produce very much power.
Posted By: Ichabod Re: 12VAC - 06/05/04 09:46 AM
Check the rating of your transformer. If it's really rated 2.5 amps then it's good for only 30 watts and is probably overloaded. You need to check the voltage at the pumps.
Posted By: Trumpy Re: 12VAC - 06/05/04 10:53 AM
Ok Bill,
My guess would be with the length of run, you are not getting enough voltage at the furtherest end of your run.
You can run a pump like that on a 12V circuit as long as it is run like a ring circuit, with the lighting on it too.
Most ELV pumps are of the Shaded Pole type, wound to a certain voltage and they only rotate one way, and they only work on AC!.
Col,
Just make sure that your wires are large enough to carry the current.
Please if you have any more questions, fire away, mate!!. [Linked Image]
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