Powering a 12v pump on household -- power suply help requested!

Hello all this is my first post here at DIY.

I am basically looking for a good solid 110v - to - 12v power converter to power a 12v pump on household current. Feel free to just look at the pictures and skip to the end.

I build and restore vintage motorcycles, and have a trusty 30L (8gallon) ultrasonic cleaner, affectionately named Screech. I am more or less finished building a DIY filtration system for it, but have one hang up with powering the pump and am hoping for a little input to nudge me toward the finish.

Here are some pictures of my set up:


If you've ever worked with a big, multi frequency ultrasonic cleaner, you'll know why I <3 Screech.



NOTE: you can sort of see that the pump's wires terminate with battery clamps. This is not a good picture because you can't see much of the stainless steel rolling cart on which Screech is sitting. It has some shelving plus room for a spare insulated tank which holds an alternative cleaning solution. The insulated tanks are nice because while Screech has an integrated heater, it takes a while to obtain operating temperature. Sometimes I switch back and forth between solutions during a job. This way they stay warm longer.



The pump is set up to allow for two fluid inputs and two outputs. This will let me (1) constantly cycle Screech's cleaning solution through filtration and back into the Screech, (2) use the pump to empty Screech's solution into a second tank, (3) suck a new solution out of a third tank, up into Screech. As mentioned before, I have several tanks for different solutions. I used to have to lift and pour the big, heavy tanks by hand. UGH! What a pain -- not to mention chemical spill yucky!




Here is the pump in question.



My problem has to do with the pump. It is 12v, and I need to power it with my standard 110v household current. In all honesty, I wish I could find a similar 200-ish gallon per hour, 110v pump, but have not been able to find one. Now that this one is plumbed in, I am committed to using it. The pump is a China-made "Pacific Hydrostar," bought from Harbor Freight, their part # 09576 (LINK).
Here are its advertised specs: 12V DC, 50 Watt, Amps: 7.5 start, 5 continuous

I am fishing for an appropriate 110v to 12v power supply for this pump. I am not very experienced at shopping for power supplies -- several months ago I bought one from a China-based eBay seller, and while its numbers looked OK on paper, it was disappointingly small, and its wires were WAY too thin to power my pump for all-day use. It accidentally got wet, and I never got to try it. The label with its specs fell off (and I don't remember its advertised specs). I'm pretty sure it was basically just a paperweight -- even before it got drenched.


Once again, here are its advertised specs: 12V DC, 50 Watt, Amps: 7.5 start, 5 continuous
Assuming that the pump's start up will require (+/-) 8 amps after it starts to get worn out, then:
8amps * 12v = 96w (hmm... this is about 90% more than the labeled specs....)
96w / 120v = 0.8 amps ( I have a hard time believing the pump will actually require that little amperage.)
There also will be some loss, considering the pump and converter, probably a lot of loss.... So if I am more or less correct, it looks like a 1 amp converter should be just fine for powering my pump. At least on paper.

HOWEVER, my old school 2amp car charger (2-10-55 selectable) does not consistently start the pump -- after connecting the clamps (and nothing happening) I have to switch the charger to 10amps, then back to 2amps. This might be from some sort of protecting circuit in the charger, I don't know.... Once the pump gets going, it seems to like the juice, and everything works well at 2 amps. It REALLY likes the 10 amp setting. I have not measured the flow, but I would guess that the 2amp setting appears to run the pump fairly close to the advertised 200gph -- about 3.33 gal/ minute, maybe a little less.

Having said all that, I have two questions:
1. Since the pump's power cord terminates with simple battery clamps, I would assume that its intended use is connected to a 12v marine battery array -- which puts out LOTS more juice than 2amps. If this is the case, as long as its getting 12v, do I need to worry about overpowering this little pump?

2. Then the second question is the obvious, what would be the ideal power supply for this pump, and can anyone recommend a specific prodct that will be good for 3-8 hours of continuous use, hopefully something priced around $30 or less, and available in the USA as I am running out of funds and patience for this project. eBay links would be very helpful here.

Thanks for your input, corrections, suggestions, and/or feed back.

Peace and grease,
-Steve

 

The pump will draw the current it needs, so you need to make sure the power supply can deliver at least 8 amps. More won't hurt, but less could burn out the power supply.

Why not continue to use the 10-amp charger?

 

Thanks for the reply. While my battery charger works well enough for testing the pump, it is a tool that I regularly use in the workshop. I am looking for a power supply I can wire in and forget -- something designated primarily for powering the pump. Regarding the car charger, I am a little concerned about this: The pump is rated at 5 amps continuous. If it "will draw the current it needs," why does it run well on the car charger's 10amp setting, but run really well on the charger's 55amp setting? --->Is it getting too much juice on the 55amp setting (enough that will damage the pump), or is the pump maybe still not getting enough at the 10amp setting? It seems that almost any 12v marine battery setup would deliver greater than 55amps. I guess I am still trying to fully understand these dynamics. Thanks! -Steve

 

How about a small deep cycle battery and just charge it when not in use?

 

Since I will occasionally be using the filtration continuously for 5-8 hours, I don't think the battery would work for me. Thanks! -Steve

 

Google is your friend. https://www.google.com/search?as_q=d...pe=&as_rights=

 

Thanks ray2047 for your valuable contribution to this discussion. Reading the full post also is your friend. I have spent dozens of hours googling this subject. I have already purchased one converter that failed to meet my needs. I am asking for the personal opinion of folks who have bought and used similar converters to help me make an informed decision about what is a good one for this application. Best wishes, -Steve

 

Ok, you can't say "Feel free to just look at the pictures and skip to the end" and then "Reading the full post also is your friend" - that's not fair.

 

I would look at a March magnetic drive pump. They are commonly available in the size you need for about $150. 110/120 volt AC continuous duty operation and they have many models able to handle various chemicals and the magnetic drive ones do not have a shaft seal to worry about.

Oh, I'm skipping over the novel, the cheap DC pump and wanting a high output continuous duty power supply for less than $30. That's a complex solution to a simple problem.

 

"Ok, you can't say "Feel free to just look at the pictures and skip to the end" and then "Reading the full post also is your friend" - that's not fair." Fair enough. =)

 

Sample power supplies

Good thing is, you don't need regulated. 13.8 volts is also OK to run a 12v pump.

 

Pilot Dane made a good suggestion. Ditch the $40 12v pump, and just buy a 110v one. So after sorting out what I would need to do to make the 12v pump work correctly (with your help!), I realized it would be difficult to do this for less than around $80. While it would be nice to have a nice quality power supply powering the pump and otherwise sitting around, just in case I need it for some random project, it makes the most sense to to just buy a 110v pump. I originally did not buy a 110 pump because at the time I was unable to find any that would fit my needs for under $200 dollars, which was out of my budget. But I was able to find several good ones, both new and used for under $50, and that is the best solution to my needs. Thank you very much for your help, and after all the parts have arrived and installed, I will post a picture of the finished project. thanks again, -Steve