Hi guys. So I was working on a hydraulic pack yesterday. It had a faulty coil so I replaced. 110VAC 33W. When we tried to operate the cone on the screen left or right on the push buttons the cone turned the same way. Then at intervals it changed and then both coils sent it in the same direction. I checked the push buttons and discovered when one was pushed it back fed voltage through to the other one push button through the opposite coil. Checking the hydraulic circuit I found that another valve was energized at the same time for oil return I presume. I discovered that this had been changed at some point and replaced with a 96VDC coil on a 110VAC circuit.When I disconnected the dc coil the cone push buttons operated as Normal and I wasnt getting any back voltage, problem solved, right? Only I connected the dc back on and it continued to work as normal as it has been before it started giving issues. Can anyone explain?

 

Incorrect connection or faulty wiring insultion when disturbed.

 

Incorrect connection or faulty wiring insultion when disturbed.

Any ideas why the 96vdc coil was causing the strange operation of the machine? I know it should have been ac as the circuit voltage was 110vac .

 

You should not operate a DC solenoid on AC all you need is a small bridge rectifier on the supply to the individual valve.
It will operate much more efficiently.
BTW if you do the reverse, AC sol on DC, you will burn it out.
Max.

 

You should not operate a DC solenoid on AC all you need is a small bridge rectifier on the supply to the individual valve.
It will operate much more efficiently.
BTW if you do the reverse, AC sol on DC, you will burn it out.
Max.

Cheers guys .This I already know. I did not fit the dc coil and I know how to remedy the issue. I just don't understand for the life of me why it's been working then all of a sudden causing funny wonders in the hydraulic pack. I suppose I was looking more of a scientific answer lol

 

Scientific answer?. I suppose one could postulate a theory and write equations using Kirchoffs laws or a set of Maxwells electromagnetic field equations. Would that help.
Expecting anyone to answer your question at a distance is a bit much. There is no circuit diagram and no mechanical layout or any thing else to base a reliable answer on, and even then it would be a guess.
i might even ask you why does my 6v plug pack no longer work.
I still suggest it incorrect connection or a wire fault. Lets us know when you find out.