LBrown59 said:
I tried it out yesterday for the first time.
The transformer would run the pump but the pump would not pump any fuel.
I then hooked up the pump to my truck battery and the pump worked fine transferring the fuel.
Now I am looking for a transformer that will convert 110 volts AC to 12 volts DC.
I don't know what to get or where to find it.
Anybody got any tips?
Well, strictly speaking transformers take in AC and put out AC. They may change the voltage but are strictly AC in and AC out. You are probably looking for a DC power supply that operates on 120 VAC and puts out 12 VDC or thereabouts.
Do you have the specs on your pump? Do you know how much current it takes to run it? If not, then you need to find out in order to get the right size power supply. A power supply isn't terribly expensive (but not trivial)but why waste money getting one way too big? So, job one is to measure the current consumption of the pump when it is operated off of a well charged 12 volt battery (jumper cables from car is fine.)
Armed with the nominal voltage (what we call a 12 volt battery in good shape is closer to 13.6 to 14.2 volts) and the current at that voltage we can then shop for a power supply. My recommendation (nearly 60 years of electronics experience, I started before grade school) is to get a power supply capable of at least 20% more than you need so it will not be strained or overheat and will last longer trouble free.
There are hoards of sources of supply and DIY is not tough for this sort of application and can save some $. I would be pleased to help further but until I know the current supply requirement I can't take it further except to suggest a little experiment.
If you have a battery charger that is rated for at least 6-10 amps, hook it up to the pump and see how well it pumps and how many amps the meter on the charger says it takes to run the pump. If the charger's meter goes to full deflection then stop the test as the charger is not powerful enough.
Depending on your circumstances you may be better served to buy a more powerful battery charger (if you don't have one that can run the pump without it pegging the meter) and when you aren't using it to power the pump you have it as a battery charger.
Often a power supply has lots more internal circuitry than a charger since it has to filter and smooth the current to imitate a batteries smooth output. A pump is not a fussy current consumer and should be happy with the output of a charger.
If you have a charger or access to one for a test, give it a whorl and see what you get. if it doesn't peg the amp meter on the charger or come too close to doing so the charger should do the job.
An off the shelf power supply new in the box usually costs significantly more than the equivalent charger. Just don't try to run a radio or such off the charger.
Another alternative is a battery maintainer (Under $10 at HF) and a fairly good shape car type battery working as a team to supply power to your pump.
Pat