12v auto pump from 110v?

Can a 12v windshield wiper pump be run from a wall wart? I am putting together a mist system for a terrarium, so it will run about 1 minute

2-3 times a day or so. If it will run from a wall wart any suggestions would be great.

Todd

Reply to
T-n-T
Loading thread data ...

I bought one for home experiments a few years ago, and from experience, they get pretty warm within a few seconds, and they're not meant for continuous use. I also think they don't like to be run dry, but running dry for a second or so shouldn't hurt it too badly.

Make sure your wall-wart can provide the necessary current.

Other than that, knock yourself out. ;-)

Michael

Reply to
mrdarrett

If the wall wart has a rectified (DC) output and a reasonably close to 12 volt output and enough current capacity to run the motor, then it should work just fine.

Reply to
John Popelish

Reply to
T-n-T

Guessing about an amp or so.

You can always run an experiment to find out... get a digital multimeter, set it to measure current, and connect it in SERIES with the windshield wiper motor, connected temporarily to your car battery (small alligator clips work great).

Make sure the pump is sucking water, even if it's just cycling through a bucket, to get a reading for while the pump is under load (and so you won't run it try, ruining it). And don't get it wet, and don't let any wires touch the car metal ground...

Guys, did I leave anything out..?

Michael

Reply to
mrdarrett

Radio Shack makes an A/C adapter with a "cigarette lighter" receptacle that can supply several amps. I used one once to test an automotive product without having to have a lead-acid battery in the lab.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

Wrong question, You want to know how much current the pump motor draws at

12V, I suspect the current needed will be printed or etched on the pump motor. I also guess it could be several Amps.

Don

Reply to
Don Bowey

And don't forget the startup surge current, which can be several factors above steady-state current draw.

I don't recall my pump motor specifying the current draw...

FWIW, I ran mine from 4 D cells (6V), which was just fine with the low flowrates I was using.

Michael

Reply to
mrdarrett

If all you need is a mist for a terrarium, then a windshield washer motor is probably overkill - you don't need anywheres near that much of a flow rate. I'd check aquarium filter pumps, and that sort of thing. The fun part of the project is going to be finding nozzles, and getting them hooked up. :-)

Or, you could go totally goofy, and get hand sprayers and arrange a little motor and cam to press the trigger a few times. ;-)

Good Luck! Rich

Reply to
Rich Grise

The washer pump? Yes, several amps. More current than you'd realize, they are terribly inefficient. And noisy.

There are several fuel pump designs that will work with water! (not the rotary ones, but there are designs that use a plunger with a solenoid driver). They may do a better job doing what you want. (Big may, not sure if they'd last an incredibly long time).

Reply to
PeterD

What happens if you try to use water with the rotary ones?

I once replaced a fuel pump on a Crown Victoria, sold the car and had the pump die again the day before I was supposed to deliver the car to the buyer. @#$@#%*( The deal fell through of course, and I got to replace the pump

*again*. The second time around there was so little time left the car was sold to a dealer for next to nothing. @#@#$%!
Reply to
Joel Kolstad

T-n-T wrote in news:071220060930159427% snipped-for-privacy@donobi.net:

Tod,

Forget the windshild washer pumps!

I tried using them (several different ones) for an automatic Christmas tree watering system. They only had to pump for a minute or so a couple of times a day to refill the stand's bowl. Every one melted the bearings. The bearings are plastic. Think about how they are designed to be used. A couple of brief one second runs to get a little juice on the windshield. They can't stand the heat generated by running them for "long" periods. I finally went to the miniature decorative fountain pumps, but these would not have enough pressure for your purpose.

Ken

Reply to
Ken Moffett

Wow, aren't fuel pumps kind of expensive? Kragen lists them starting at $100+.

These pumps are looking better and better...

formatting link
formatting link

I'm going to need a pump that can pump a conductive fluid (dissolved baking soda), and I'd *really* prefer *not* to have to use a submersible aquarium pump. 110VAC... submersible pump... conductive fluid... not a safe mix.

Michael

Reply to
mrdarrett

Is it "tap" water (pressurized)? If so just use a mist nozzle from an outdoor "bubbler" irrigation system, and a solenoid valve body (nominally 28V, but AC, so all you need is a transformer).

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

I have a 12 volt submersible pump in an outside pond that has been operating at the bottom of the pond for several years with no problem.

The HF pumps look far too big for the job but you have not told us ho big your Terrarium is.

--
John G
Reply to
John G

Just the little squirter pump motor?

I measured 2A continuous (more than I expected, but all auto electrics seems suprisingly inefficient) that'd be a large wall-wart or a small brick. or it could just be my cheap DMM playing up.

Bye. Jasen

Reply to
jasen

I've seen central-locking actuators used for that.

--
Bye.
   Jasen
 Click to see the full signature
Reply to
jasen

If it is all stainless, it might be OK. Some are, but they are expensive. A non-stainless (cheap ones) would rust quickly.

The plunger/solenoid ones are mostly plastic.

Reply to
PeterD

I get the plunger/solenoid pumps for about $35 to $40 at the parts store (I do get a discount, but not that much). The rotary ones are expensive, even the cheap ones are more than $100!

Regardless these are not an optimal solution, IMHO. Nothing beats using the right pump for the job.

Now, thinking about it, maybe Northern Tools (used to be Northern Hydraulic) has lots of pumps, and probably has just what the OP wants.

Reply to
PeterD

Yep, that confirms what I said earlier, so I'd say your cheap DMM was doing OK!

They are *really* inefficient!

Reply to
PeterD

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.