Switch Help for 2 Grinders on 1 VFD

G

Gables

Joined
Dec 20, 2009
Messages
40
Switch.jpg



This is a two on, one off 12 pole switch rated at 500v, 20 amp. I have 3 phase plus ground coming out of vfd and need to feed to two like grinder motors. There were no instructions with the switch. Can anyone offer assistance? As show one side of terminals is labelled 1,3,5,7,9,11 and the other side is 4,2,8,6,12,10.
 
Thanks Patrice. One more thing to note is I could not get any continuity readings to register at any positions on this switch.
 
Gables said:
Thanks Patrice. One more thing to note is I could not get any continuity readings to register at any positions on this switch.
Click to expand...

If that's really true and you didn't make a mistake in testing it.

Then that switch is scrap.


I do doubt that it has zero contact on any terminals at any position.
That's just too much fail all at once.

Start by making a chart like this



Yes I know 1 and 2 is the same as 2 and 1, - you could probably only have to do half the chart
but you see, I didn't miss any combinations and it makes that chart easy to read.

Then repeat that for each switch position.

Then show us the chart that summarizes them.
Something like 363 possible variations - did you test them all already ??

How are you testing continuity, a beeper, a light, a meter?
What settings? did you test the tester first to prove it works ?

switchchart.jpg
 
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Thanks for the suggestions. I tested the meter and tested it on a couple of other switches and know it is working. I did all of the combinations and here is what I found.

Position 1: 9 and 10 common; 11 and 12 common

Position 0: 5 and 6 common; 7 and 8 common

Position 2: 1 and 2 common; 3 and 4 common

Obviously I am learning as I go. So can I use this for 3 phase?
 
Gables said:
Thanks for the suggestions. I tested the meter and tested it on a couple of other switches and know it is working. I did all of the combinations and here is what I found.

Position 1: 9 and 10 common; 11 and 12 common

Position 0: 5 and 6 common; 7 and 8 common

Position 2: 1 and 2 common; 3 and 4 common

Obviously I am learning as I go. So can I use this for 3 phase?
Click to expand...

Not as you have described it above.

You will need tpdt - three pairs continuity in each direction.
Triple pole, double THROW switch center off EDITED A MISTAKE

123 Position 1
456 Middle Off
789 Position 2

If you tested continuity, you would have three pairs continuity in each direction.


Position 1
1-4, 2-5, 3-6

Position 2
4-7, 5-8, 6-9


VFD out to middle pins 456
and a motor on each side 123 and the other on 789





I've ripped this photo from google, the pin numbers don't match what I've written above.

images
 
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Thanks for your help. This makes sense to me. What doesn't make sense is how my switch tested. I ran through all the combinations twice and the combinations match. I assume I can therefore only use this switch if I had three separate single phase feeds and three separate single phase devices. It is just one switch instead of three separate on/off switches.
 
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