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Solenoid Help

Posted: Fri Jul 11, 2008 3:07 pm
by )DEMON(
The solenoid on my rainbird sprinkler valve is just not actuating. I have three 9v cells connected in series as a power source. It says 24v AC and I have 27v DC, is this a problem?

How can fix this problem? I have roughly an hour starting now to fix this. :evil:

**Nevermind, there is no way I am going to have this fixed in time.

Posted: Fri Jul 11, 2008 6:19 pm
by jrrdw
I'm gonna answer anyway. You need a AC to DC converter. :P

Posted: Fri Jul 11, 2008 6:28 pm
by Hotwired
Ehhh.... you must mean a DC to AC converter surely?

Posted: Fri Jul 11, 2008 7:04 pm
by jrrdw
Hotwired wrote:Ehhh.... you must mean a DC to AC converter surely?
Mind reader! :P

Posted: Fri Jul 11, 2008 7:17 pm
by frankrede
reverse the polarity.

Posted: Fri Jul 11, 2008 7:26 pm
by jrrdw
frankrede wrote:reverse the polarity.
That wont make the current alternate.

Posted: Fri Jul 11, 2008 8:53 pm
by blind909
You could modify it for pnuematic actuation.

Posted: Fri Jul 11, 2008 9:25 pm
by iisthemuffin
I mean this with no offense blind. Im sure you intended well, but he did not ask how to make it better or anything of that sort. He asked how to make what he had work. And i agree that pneumatic actuation would be better, but like i said, its not what he had asked for.

DEMON, im confused as to why it wouldnt work. I dont see why it wouldnt. Ive taken many things that run on batterys and hook them up to the wall with a cord. Maybe its different. Im no genious. You could buy the convertor, or you could search google and try to fix the current flow yourself.

Heck, who knows, That may not even be your pronblem.

Posted: Fri Jul 11, 2008 9:58 pm
by knappengineering
I don't see why this wouldn't work. I have run a sprinkler solenoid off of a 12v DC gel cell for my rocket base, no problems at all. Are you sure you have your 9v batteries wired correctly?

Posted: Fri Jul 11, 2008 10:04 pm
by iisthemuffin
Make sure you have it all wired like this. And then give it a try.

Re: Solenoid Help

Posted: Sat Jul 12, 2008 10:53 am
by jimmy101
)DEMON( wrote:The solenoid on my rainbird sprinkler valve is just not actuating. I have three 9v cells connected in series as a power source. It says 24v AC and I have 27v DC, is this a problem?

How can fix this problem? I have roughly an hour starting now to fix this. :evil:

**Nevermind, there is no way I am going to have this fixed in time.
Running an AC device with DC is hit or miss. Somethings (like lightbulbs) don't care. Other things do care. A solenoid really shouldn't care about the polarity as long as it can't cycle anywhere near as fast as the 60Hz AC signal. A small solenoid might be able to oscilate at 60Hz so there may be a diode in the solenoid to convert the AC to pulsed DC. If that is the case then the solenoid is acutally running on ~12V.

Try switching the + and - leads. You might also be able to get by with just 9V or 18V.

Posted: Sat Jul 12, 2008 11:22 am
by TurboSuper
Test it with a multimeter (ohmmeter mode should do it)...make sure you didn't blow anything. Unless it's more complicated, a solenoid is generally low resistance.

Posted: Sat Jul 12, 2008 12:07 pm
by jimmy101
TurboSuper wrote:Test it with a multimeter (ohmmeter mode should do it)...make sure you didn't blow anything. Unless it's more complicated, a solenoid is generally low resistance.
Try the ohm mode with the probes connnected both ways. If there is an internal diode then you'll only get continuity with one polarity.

Posted: Sun Jul 13, 2008 8:40 am
by psycix
frankrede wrote:reverse the polarity.
If you can do that over 50 or 60 times per second, then that will work :D

But what about just modding the valve with a blowgun?

Posted: Mon Jul 14, 2008 10:58 am
by )DEMON(
Well I have not got it working yet. I am using a remote activation system for the solenoid, so I can't mod it for pneumatic activation. Is there a small inverter of some sort that I could use to turn the DC current into AC current? I have looked around but all I can find is friggen huge ones that I can't use in my system.
Try the ohm mode with the probes connnected both ways. If there is an internal diode then you'll only get continuity with one polarity.
Huh?