ON-ON switch vs ON-NONE-ON

[Back2Volts]

Are they the same or does the NONE imply a middle stop position where no connections are made ?

[xani]

http://www.carlingtech.com/basic-circuit-function#10

Seems like what you want would be ON-OFF-ON. If in doubt, look in the datasheet

[rstofer]

Corrected my oopsie!  It's too early in the day...

ON-NONE-ON has 2 positions - there is no center position
ON-OFF-ON has 3 positions
There are some ON-ON-ON switches around but they're not common.

[Back2Volts]

ON-NONE-ON has 3 positions
ON-ON has two positions
There are some ON-ON-ON switches around but they're not common.

Not according to the Carling document posted by xani:


ON-NONE-ON

The ON-NONE-ON or ON-ON circuit is a maintained, double throw, two-position switch circuit. In general, for basic unlighted single pole switches, ON positions close at the circuit at switch terminals 1 & 2 and 2 & 3. For basic unlighted double pole switches, the circuit is closed at terminals 1 & 2 and 2 & 3; 4 & 5 and 5 & 6.

If the switch is mounted vertically, you would press the top of a rocker actuator or push a toggle actuator upward to set the switch to the first ON position. You would press the bottom of the rocker or move a toggle downward to set the switch to the second ON position. This switch circuit does not have an OFF position, where all switching circuits would be open.

[rstofer]

ON-NONE-ON has 3 positions
ON-ON has two positions
There are some ON-ON-ON switches around but they're not common.

Not according to the Carling document posted by xani:


ON-NONE-ON

The ON-NONE-ON or ON-ON circuit is a maintained, double throw, two-position switch circuit. In general, for basic unlighted single pole switches, ON positions close at the circuit at switch terminals 1 & 2 and 2 & 3. For basic unlighted double pole switches, the circuit is closed at terminals 1 & 2 and 2 & 3; 4 & 5 and 5 & 6.

If the switch is mounted vertically, you would press the top of a rocker actuator or push a toggle actuator upward to set the switch to the first ON position. You would press the bottom of the rocker or move a toggle downward to set the switch to the second ON position. This switch circuit does not have an OFF position, where all switching circuits would be open.

You are correct.  ON-OFF-ON is the 3 position variant.

[retrolefty]

Are they the same or does the NONE imply a middle stop position where no connections are made ?

 It is indeed a 3 possible position switch. Some on-none-on switches can be had with a momentary spring return on either on or just one of the on positions.

[Back2Volts]

Are they the same or does the NONE imply a middle stop position where no connections are made ?

 It is indeed a 3 possible position switch. Some on-none-on switches can be had with a momentary spring return on either on or just one of the on positions.

Are you saying that the Carling description is wrong ?

[retrolefty]

Are they the same or does the NONE imply a middle stop position where no connections are made ?

 It is indeed a 3 possible position switch. Some on-none-on switches can be had with a momentary spring return on either on or just one of the on positions.

Are you saying that the Carling description is wrong ?

 I guess I could be wrong according to Carling (which I've never heard of). I just never heard of a simple on/off switch referred to as on/none/off. I guess the problem is that a given switch has both an electrical description (spst,spdt,dpdt,etc) and a mechanical description (toggle, momentary, center off, etc.

 After a few misordered switches in the 70s I alway try and find a datasheet for any specific switch and if not available then pass on it. Pots can be just as error prone to order for all the various types (taper, gangs, detented, etc) Some stereo volume/balance pots from the 70s can be near impossible to source anymore.

[John Coloccia]

I think the On-On and On-None-On thing comes about because engineers love spreadsheets and it's awkward to leave the "center" column blank on the spreadsheet...so you say "None" instead, and all is right with the world.

[Psi]

be away that some On-On-On 3 position switches have 6 terminals and you have to short some pairs to "make" a 3-way switch. While others have 8 terminals and work as you would expect.