What is AC and DC voltage rating of switches

I am looking for a PCB mount SP3T

I believe the point is, that this switch does not have a single pole (common connection) that is switched between 3 contacts.

If you do not need that, then it will work okay. Or the 5 contact version can be made to work as a SP3T switch with a little creative wiring.

It is not about safety.
 
I only need to switch between triode, UL and penthode, I don't want more than 3 positions, it gets more confusing. As long as it is break before make, I don't see any reason to use a 5 position just to have a break in between.
 
I may be missing something here. I am having one of my sleepless night due to my health and my meds are making a little groggy.

But it is not about having a break in between.

The switch in your example is not a SP3T switch.

Can you show me how you will have the switch connected?
 
if its shorting adjacent positions and it only has 3 detents I don't know that this will work. It shorts adjacent contacts to connect, so say fully counter-clockwise it connects terminals 1 and 2. One click over will give you 2 and 3. One more click over will be 3 and 4.

What you want for this is a common terminal with the screen tied to it, and your various terminals would go to the plate, the UL tap, or the B+ supply as appropriate for the mode.
 
There seems to be some confusion. I just loaded the data sheet, but

This is what is shown on the web page and it does not match the data sheet

upload_2017-11-22_7-30-28.png



From the manufacture's data sheet.

upload_2017-11-22_7-28-11.png
 
BTW, I don't particularly like this switch, I am more than happy if you guys have a better switch. All I want is

1) PCB mount and top adjust. As ultimately it's going to be a hole on the top of the chassis and use a screw drive to adjust. I can even accept a rocker switch.

2) I can even give up the triode mode and use a SPDT ON-ON two position switch. This means a rocker switch is acceptable, but I still rather be pcb mounted.
 
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I don't understand the shorting adjacent pairs. It is break before make, how can it be shorting adjacent pairs.

You have to look at the diagram.

The part that I marked in red is not a common connection. It is not connected to anything outside of the switch.

In the position that is shown, it bridges (connects together) terminals 1 and 10. One click clockwise, terminals 1 and 2 to are connected together, one more click clockwise, terminals 2 and 3 are connected together, one more click clockwise and terminals 3 and 4 are connected together and so on.

There is not a single pole connected to 3 selectable connections, this is key. You are thinking in terms of the part that I marked in red being the common connection and it is not if the data sheet can be believed.

Again, as it says, if this is correct for the switch, there is no common terminal like there would be with a SP3T switch.


upload_2017-11-22_11-47-17.png
 
Yes, the adjacent pairs thing is confusing. I think you can get what you want with the 3-position DP version, R203, if you wire "common" to 1 and 7, and outputs to 10, 2, and 8 (for example).
 
I might have to give up on this, I was hoping I can switch back and fore on the fly. But if I have to adjust bias for each selection, that defeats the point of having easy switching all together.
 
Alan, do not worry about the DC voltage ratings.

When you look a switch and the DC voltage rating is less than the AC voltage rating, that is usually at the full rated current of the switch.

When you reduce the current that the switch is carrying, you reduce the current of the arc when the contact is broken. This allows the switch to work okay at higher DC voltages (although there might be some accelerated wear to the contacts, likely not a lot) Note on the switch that you reference, the 125 volt DC rating applies at a much lower current (10 times).

With your project, like many others the devil is in the details. There are always solutions and my OCDness would likely drive me.
 
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