3 Position key switch

antlyn

Evening all,

I have a dilly of a pickle. I'm installing a 3 position key switch into a control panel for a friend of mine (see pics below) He has purchased the switch and contacts ready made from the equipment supplier. There are two normally open contacts and three normally closed (see pics). I have it wired up correctly so far, however there is one normally closed contact I cannot wire correctly. It requires the contacts to be made in the 0 position, which it is as it is n/c, however by moving the switch to the ii position alters the switch and the contacts are made again. According to the drawing for the equipment the contacts should only be made in the 0 position. Any ideas? I'm completely stumped!

frankmul

antlyn wrote: »

Evening all,

I have a dilly of a pickle. I'm installing a 3 position key switch into a control panel for a friend of mine (see pics below) He has purchased the switch and contacts ready made from the equipment supplier. There are two normally open contacts and three normally closed (see pics). I have it wired up correctly so far, however there is one normally closed contact I cannot wire correctly. It requires the contacts to be made in the 0 position, which it is as it is n/c, however by moving the switch to the ii position alters the switch and the contacts are made again. According to the drawing for the equipment the contacts should only be made in the 0 position. Any ideas? I'm completely stumped!

did you take the contact of the switch and look at the back of the switch as you rotate the key. there should be a mechanism which operates the row on contact as the key is turned.
the switch could be like the ignition switch in a car. off/on/start. checking the mechanism will tell you how it should work.

Bruthal

antlyn wrote: »

Evening all,

I have a dilly of a pickle. I'm installing a 3 position key switch into a control panel for a friend of mine (see pics below) He has purchased the switch and contacts ready made from the equipment supplier. There are two normally open contacts and three normally closed (see pics). I have it wired up correctly so far, however there is one normally closed contact I cannot wire correctly. It requires the contacts to be made in the 0 position, which it is as it is n/c, however by moving the switch to the ii position alters the switch and the contacts are made again. According to the drawing for the equipment the contacts should only be made in the 0 position. Any ideas? I'm completely stumped!

It may be possible that the contacts closing again in position 2 dont matter.

It all depends on exactly what the switch is doing or supposed to do with regards to what its connected to. Have you tried the machine, or are just testing the switch itself with a tester?

antlyn

Thanks for the replies. According to my drawing the contacts should only be made in position 0 as when they make they sound an alarm, hence they should only make in one position.

Bruthal

antlyn wrote: »

Thanks for the replies. According to my drawing the contacts should only be made in position 0 as when they make they sound an alarm, hence they should only make in one position.

Have you tested the switch in the machine? Without seeing the machine diagram, its all guesswork for posters.

For instance, it could be possible that the alarm is powered through a relay in the machine, so it wouldnt sound except if the key is in position 0. Thats only a random example to show that the closed contact alone might not sound the alarm.

If the intended design was that the contact only ever closes in a single switch position, then either the switch is wrong, or the contacts themselves are incorrectly fitted to the switch mounting frame, as in a N/C fitted where a N/O should be. Do all the N/C contacts close together in position 0 is another question? Have you tested for that?

antlyn

Bruthal wrote: »

Have you tested the switch in the machine? Without seeing the machine diagram, its all guesswork for posters.

For instance, it could be possible that the alarm is powered through a relay in the machine, so it wouldnt sound except if the key is in position 0. Thats only a random example to show that the closed contact alone might not sound the alarm.

If the intended design was that the contact only ever closes in a single switch position, then either the switch is wrong, or the contacts themselves are incorrectly fitted to the switch mounting frame, as in a N/C fitted where a N/O should be. Do all the N/C contacts close together in position 0 is another question? Have you tested for that?

Some food for thought there, thanks. Will try again tomorrow evening and will be back here with a circuit diagram if I'm still in trouble.

Bruthal

antlyn wrote: »

Some food for thought there, thanks. Will try again tomorrow evening and will be back here with a circuit diagram if I'm still in trouble.

Yes just check each contact, and write down what each n/o and each n/c contact state is for each switch position, keeping a note of each switch with a label or labelled photo. That might guide you along as to exactly when each switch contact is open or closed for each key position, which might be of some help to you in conjunction with the machine diagram.

unit 1

Its hard to tell from your photo but have you mounted the nc switch in the middle position. In the middle it should be closed but open in any other position