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You can use a 9 volt battery I think, however it may not open as fast as a blow gun would. Note that I have a 1 1/2 inch dust valve like this, not the same brand, and I was able to just use a blow gun, it needed no modification!!

jackssmirkingrevenge wrote:

Atattack wrote:JSR, I like the idea of using valve as is with a battery. This valve is 110VAC 50/60Hz.

I would think you'd need an inverter, you can get them pretty cheap on eBay - although thinking about it if I'm not mistaken AC solenoids can run on DC.

An inverter is not needed.

Due to the way AC works in an inductor to limit current, an AC valve will work on a lower voltage DC. How much lower can be calculated. Let me explain.

The strength of a magnetic field on a coil of wire is directly related to current in the coil, not voltage. This is the important spec.. Current.

In AC current is limited by Resistance and Inductance. In DC current is limited by only Resistance, so a lower Voltage can produce the same current. How much lower? Depends on the resistance. This can be measured by a meter and sometimes this is stated in the spec.


The clues you need are in the section in the PDF listing the solenoid specifications. They don't give ohms, but it does give inrush apparent VA. This basically states the AC current that it pulls is the same as a 20 Watt (or 40 Watt depending on model) resistor on 120 Volts. Using this, the apparent AC resistance can be calculated (resistance and inductance).

When you get the valve you can measure the coil DC resistance with a meter. It will be lower than the AC impedance. Using Ohm's law, the DC voltage needed to produce the same current can be calculated.

When you get the valve and measure the DC resistance, I can do the math for you.

In reality, most 120 Volt AC valves can be operated on about 1/2 of the AC value with DC. For example 24 VAC sprinkler valves or gas appliance valves will work fine on 12 Volts DC. I suspect that valve will work fine on 3-5 9 volt batteries connected in series for about 27-45 volts DC.

You will not need an AC inverter to power the valve.

For a real world example, this thread covers measuring my sprinkler valves.
http://www.spudfiles.com/forums/questio ... 18083.html

Tech you make everything sound more complicated than it actually is,lol! In other words, splice together 3 9 volt batteries and this will actuate the valve, right???

Actually I kinda like tech's in-depth explanations of basic electronic concepts. It helps those of us who want to branch out into other areas get a foothold somewhere.

Agreed, tech has a wealth of knowledge, and even when he goes beyond answering the question, all info is pertinent and useful. Very valued member of the forum, I say.

Dont get me wrong, I wasnt saying I didnt like it or it wasnt good, what I meant to say is professional, and, TECHnical!!

Atattack, if you don't mind my asking, why do you need this wired up? I understand the wireless shooting, but if its for air I doubt that you would need to be standing say 50ft away to shoot it. Don't get me wrong, I'm not trying to stop you from doing it.

If you are willing to sacrifice the solenoid, I would say just replace it with a blowgun or ball valve, but if you aren't then try to drill and tap a hole next to it where you can put an elbow then a ball valve or blow gun. (If I am wrong with the drilling and tapping, please let me know so I clear that up and don't make the mistake my self in future.)

warhead052 wrote:Atattack, if you don't mind my asking, why do you need this wired up? I understand the wireless shooting, but if its for air I doubt that you would need to be standing say 50ft away to shoot it. Don't get me wrong, I'm not trying to stop you from doing it.

If you are willing to sacrifice the solenoid, I would say just replace it with a blowgun or ball valve, but if you aren't then try to drill and tap a hole next to it where you can put an elbow then a ball valve or blow gun. (If I am wrong with the drilling and tapping, please let me know so I clear that up and don't make the mistake my self in future.)

Well if you take the diagram to scale, you can see that the solenoid on this particular valve has much higher flow then a standard blowgun, and would probably yield higher performance.

I am not wanting to fire this gun from 50 feet away. I am just trying to find a valve that is metal and at least 1.25" to use on a 3" barrel.

Tech, thanks a lot for the explanation. I think I may go with the VXF2280-14-5D if I am understanding your post correctly. This model is a 24VDC and I am guessing would be easier to power than the 110VAC. I thought they made a 12VDC 1.5" but after searching I believe the largest they make in 12VDC is 1". Guessing this is due to voltage limitations but I am just guessing. Anyway, thanks Tech and look forward to your thoughts.

Actually, just found this valve that is 12vdc and is in-line which will work better.

http://www.dudadiesel.com/choose_item.php?id=2WJ40040N

The reason the larger valve is not 12 volts is because lower voltage requires higher current for the same power delivered.. Power is Volts times Amps in a DC circuit. (AC is a little more complicated when there is inductance or capacitance) For example a 40VA (Watts) valve would need 3 1/3 Amps at 12 volts and only 1 2/3 Amps at 24 volts. Due to the size of Class 2 control wire, the lower voltage is too much current for it to carry without too much loss. The 20VA valve would only draw 1 2/3 Amps at 12 volts. At 120 volts it would draw a huge 0.167 Amps.

For those learning, when the core is pulled in on an AC solonoid, the inductance goes up, so the solonoid draws less. This is why on the PDF under Solenoid Specifications, there are two values given. The higher Inrush is the current berfore the core pulls in. The hold current is after the core is pulled in. A DC coil does not have this current reduction. The inrush current value needs to be supplied to an AC coil to get it to pull in. The hold current won't open it, but will hold it open after it is open.

Technician1002 wrote:An inverter is not needed.

Thought as much hence the edit, thanks for clearing it up

Actually, just found this valve that is 12vdc and is in-line which will work better.

... considerably more expensive though.

It is, I am hoping tho to get many years use out of this gun.

Due to the wattage (17 Watts) the 12 Volt DC valve may be trying to draw more current than 9 volt transistor radios are designed to provide. I would recommend a higher current solution for the lower voltage valve. A holder for 8 AA batteries is recommended.

The 120 volt valve discussed earlier will draw less than 1/4 amp at the higher voltage, which the 9 volt batteries can supply.

Awesome, thanks a lot tech. JSR, how would this 1.5" solenoid compare to a 1" qev?

Atattack wrote:how would this 1.5" solenoid compare to a 1" qev?

It's literally 2.25 times better