Rotary Switch Question

[Timko]

I have a 3p4t switch that I want to wire for 5 different selections.

No Option
Option 1
Option 2
Option 3
Option 4

This is how I thought I could wire it.  I connected inputs to pins 5-8, and the output to Pole B.
4 - Off (nothing is wired here)
5 - Selection 1
6 - Selection 2
7 - Selection 3
8 - Selection 4

I thought that continuity for the B Pole would only happen for selection 5-8.  However, I noticed that for selection 4, continuity between the B pole and pin 8 is also selected.  Similarly, pin 4 has continuity to the B Pole in position 1, pin 5 has continuity in position 2, etc.  I'm using this switch:
https://www.taydaelectronics.com/electromechanical/switches-key-pad/rotary-switch/rotary-switch-3-pole-4-position-alpha-sr2612f.html

Should I order a 1p6t switch instead or is there a way to make this work with a 3p4t switch?

[davent]

It's just repeating itself, if your 4pole switch rotary switch has five positions it's set up wrong.

At the base of the bushing under the washer is another washer with a single tooth that goes into a slot, one of 11 under it. That is a stop that prevents the switch from turning beyond the desired number of positions. You need to reposition the tooth into the slot that gives you only 4 positions.

The body's the same for any combination of 12 positions, 1x12, 2x6, 3x4... but you can always set it to use fewer positions.

dave

[diablochris6]

Moving the little washer with the tab on it, you could essentially make a 3P4T a 1P with more throws. The catch is that you can't use poles B and C correctly anymore. It might not be the most efficient use of a rotary, but if you don't want to make a special order for a 1P6T, it will work just fine.

[Timko]

Ah, ok.  Thanks Chris!  I need to then use the A Terminal to do this, not the B I bet.  Let me try some various experiments with that.

EDIT:  Well, no dice.  I may try wiring pins 2-5 for my input, and wiring poles A & B together to be output.  I'm not sure though is that has some downstream effect though.

[davent]

On the 3P4T switch i have here, A connects to 1 in positions 1,5 & 9. A - 2 connects in position 2, 6 & 10.   A - 3, connects in positions 3, 7 & 11...

A 1 x 12 or 2 x 6 are easy to get and give you your 5 positions.
dave

[Govmnt_Lacky]

How can you have "5 selections" with a 4 throw switch?

[Timko]

How can you have "5 selections" with a 4 throw switch?

IDK.  DiabloChris had it working on one of his builds so I was trying to get it.  I ordered a 1p6t switch since I couldn't get it to work.

Thanks for the input everyone!  To be continued Saturday in the SIP build forum...

[diablochris6]

How can you have "5 selections" with a 4 throw switch?

So, i think it was a happy accident in my case. I tested all the contacts I could on the rotary (I snipped some of the unused ones off to save space) and found that somehow my A and B lugs are connected. I don't know if it was a faulty pot, or if my mangling bent something within the pot, but that is the key to getting the five positions. Even though lug B is tied to A, since B is not wired to anything else, it makes for an extra point of contact by connecting lug 5 to lug B that is linked to lug A, if that makes sense. I found one other website that explains how it's done, but his method is much more elegant and purposeful than mine was.
http://www.imajeenyus.com/electronics/20120615_modifying_rotary_switch/index.shtml

[Govmnt_Lacky]

So, i think it was a happy accident in my case. I tested all the contacts I could on the rotary (I snipped some of the unused ones off to save space) and found that somehow my A and B lugs are connected. I don't know if it was a faulty pot, or if my mangling bent something within the pot, but that is the key to getting the five positions. Even though lug B is tied to A, since B is not wired to anything else, it makes for an extra point of contact by connecting lug 5 to lug B that is linked to lug A, if that makes sense. I found one other website that explains how it's done, but his method is much more elegant and purposeful than mine was.
http://www.imajeenyus.com/electronics/20120615_modifying_rotary_switch/index.shtml

But... you still had 5 positions... right?

Position 1: A connected to B
Position 2: A connected to 1
Position 3: A connected to 2
Position 4: A connected to 3
Position 5: A connected to 4

Even with this configuration, the rotary would need 5 positions which a standard 3P4T does not have.

Better off having an adjustable 1P6T switch and solder the A & B wires together on the single pole.

[davent]

I think you'd be okay if you jumpered A,B,C,D. Chris's link, the modder had a mess of 4P3T's to use up.

dave

[diablochris6]

But... you still had 5 positions... right?

Position 1: A connected to B
Position 2: A connected to 1
Position 3: A connected to 2
Position 4: A connected to 3
Position 5: A connected to 4

Even with this configuration, the rotary would need 5 positions which a standard 3P4T does not have.

Better off having an adjustable 1P6T switch and solder the A & B wires together on the single pole.

Turns out, I am using a 4P3T in my build (I'm such a dope for not noticing it sooner). Here's the real kicker though, even though it's a 4P3T, I opened it up and notice that pins A and B are connected with one contact pad, and C and D are connected with one contact pad, essentially making this a 2P6T with extra poles? It doesn't make sense. I must have been extremely lucky when I put this together because I would not have known this unless I dismantled the rotary.

So, in all situations A is connected to B
Position 1: A connects to throw 1, but throw 1 is not connected to diodes for clipping
Position 2: A connects to throw 2
Position 3: A connects to throw 3
Position 4: A connects to throw 4 (this would be position 1 for pin B, but as mentioned above B and A are internally linked)
Position 5: A connects to throw 5 (position 2 for pin B, but see above comment)

By setting the washer to 5 positions, I can get all the clipping options I was going for. It makes sense since this 4P3T is acting like a 2P6T, but it similar results should still be attained with a "normal" rotary if pins A and B are connected.

Timko, sorry for any confusion! Obviously, I would have never known that my build was a fluke without you asking questions. Now I can update the build notes.