Permenant magnet soloniod

Hello all,

This is possibly a little off topic for this board but I thought I would see if anyone on here knew of anything.

What I'm looking for is a permanent magnet in a solenoid coil for pneumatic valves. The idea as to be able to remove the standard coil and drop this on as a direct replacement to hold a valve permanently open as if the coil was energised. This is for commissioning and fault finding purposes and also if needed to get around a problem. I'm sure I've seen them before but have no idea where or when and having searched the internet can't find anything. Any ideas?

I've not tried it but if you get a Neodymium magnet and place it at the top of the solenoid I dare say it would be strong enough to lift the actuator. I'll nip down to maintenance get a valve and try it post result here in a mo.

Yup it worked fine on a SMC - SY5120 series valve, didnt even have to take off the existing solenoid. Magnet was Neodymium 18mm dia 6mm thick. You have to have air on the valve as they are air assisted. The solenoid does not move the main actuator it just lifts the solenoid actuator to let air in and move the main, that is how they manage to move large actuators without using high current I suppose.

Thanks for that badger, I'll give it a go and report back!

danfoss has a nice ring to do this, big yellow (so you wont forget it)
it is indeed for commisioning, and i use it a lot, Not for controlling, but a cooling system needs vacuuming the entire installation and at that moment there is not always power on the controlboard.

And if your solenoid coil has the least chance of being energized while it is off of the valve, be sure to put a piece of ferrous metal (i.e., a bolt) through the coil to keep it from burning out.

You are better off not removing the coil if you can help it.

rootboy said:

And if your solenoid coil has the least chance of being energized while it is off of the valve, be sure to put a piece of ferrous metal (i.e., a bolt) through the coil to keep it from burning out.

You are better off not removing the coil if you can help it.

Click to expand...

Thats why I used the neodymium magnet. It was/is so strong I did not need to remove the solenoid coil.

As Shooter says, Danfoss makes some types. Mine is blue tho, lol:

http://www.mmcdanfossdistributors.c...anfoss-solenoid-coils/200-danfoss-test-magnet

How can you see this in between a lot of coils.
When leaving site please count the number of rings in your box, please dont forget one.

Badger said:

Thats why I used the neodymium magnet. It was/is so strong I did not need to remove the solenoid coil.

Click to expand...

Well, it was intended as a warning for those following along. But I see enough burnt out coils that I remind everybody.

We recently replaced some valves with a higher flow type and the contractor wanted us to use the quick disconnect type rather than the hard-wired ones that came with the valves. We did that and immediately the south one burned up.

Huh, that's odd. So I ohm'ed it out (~40 ohms) and ohm'ed out the remaining good one (~130 ohms). Must of been a bad coil... The coil nameplates state that these are 120 VAC so we should be good. We fire off the other one and it burns out.

So we put the original coils back in and wired the outputs to two unused outputs (since the coils took the outputs out too), and modified the program.

I went back to my desk and tried to see if this was the correct part number by searching the manufacturer's site, and rather than listing the coils by part number, they list them by coil resistance and current/watts values. What!?!

What makes it worse is that they even got it wrong for their DC coils where they list one coil as 24 VDC at a certain current with "X" resistance, and another at the same voltage and current, but at "Y" resistance.

Uhh, guys, you might want to check your math...

I had them burn up within minutes when activating them without actually putting them on the valve.

Thanks for all your help guys. For those interested, I intend on buying a couple from http://www.fridgenius.co.uk/distributors.html hope this helps.

For HVACR service many coils are 24VAC and are not interchangeable with the 24VDC. Always good to double check what they sent you.