Can anyone explain this...

[Charles Middleton]

Hi, can somebody explain to me in very simple terms the following:

- Push to make switch.

- Momentary-action

Thanks in advance,

CM.

[usenet]

A 'push to make' switch is the type used for a door-bell or similar. When you push it the switch contacts close, when you release the contacts open again.

A 'momentary-action' switch is probably different things to different people. It *could* (to some people) be the same as a 'push to make' switch. I.e. it's 'momentary' for the length of time you press the button. Alternatively (and I think this is what I'd go for) when you press the button the switch closes momentarily and then opens again even if you keep the button depressed. You then have to release the button and press it again to get another momentary closure.

Note that I have used the terms 'contacts close' and 'close/open' above on the basis that the switch has 'normally open' contacts and switches a circuit on when you actuate it. It's perfectly possible for things to be the other way about (i.e. you press to open a contact) or even for the switch to have multiple sets of contacts which do lots of different things for the period of actuation.

[Al Reynolds]

I *thought* they were the same thing.

The switch is off. You push it, and it's on, but when you release it it goes off. Perhaps momentary action means it only stays on momentarily even if the switch is still being pushed (like the power switch on some PCs).

Al

[Peter Stockdale]

Bell -push , Door bell style, perhaps.

Pete

[Charles Middleton]

Thanks all for the answers it makes total sense now. Im looking at working with a dimmable electronic ballast for my latest project. The on/off and dimming function is control via a push to make switch which seems like a simple way to set it up. Unfortunately the switch needs to be located in a prominent position and it looks unlikely I can get one to match the required decore and existing switches (brushed chrome look). Cheers, CM.

[Dave Plowman (News)]

What make switches are you using? Most makers will supply a blank plate, and you could mount a 'special' switch on that. There are many different styles of push button switches - I'm sure one would look ok.

[BigWallop]

This should answer your question:

"Push to make" switch is only in the "On" position when it's pushed in and held in. Commonly used as door bell buttons and the like.

A "Momentary Action" switch is when the switch will latch (lock) in the "On" position for a second or two by itself before releasing to the "Off" position again, or vice versa. Commonly used where a need for a long signal to start a series of relay contacts need to be established, or as a short timer for pass through lighting systems.

[Andrew Gabriel]

You can make one up using MK gridswitch or other manufacturer's equivalents, where you can get momentary action (also called retractive) switches. I have also been known the take a spring out of a retractive switch and put it into some other type of switch which uses the same moldings, but where a momentary action version was required but not available. I actually have a regular 2 gang MK switch where one of the switches is momentary action, created this way. (Not sure you can do this any more, as I think MK stopped using the same moldings in their regular Logic Plus as in their Gridswitch range.)

[Set Square]

I think I've also come across the use of the term 'momentary action' to refer to a press and release switch used in conjucntion with a latching relay. So, when once on, the load stays on until some other event causes it to switch off. You get this sort of thing on some cars for things like heated back windows. You push a button and the heater comes on and stays on - but when you turn off the ignition, it goes off and doesn't come back on again without a further button push.

[Charles Middleton]

different

I believe that they are MK. In fact I have a spare silver MK single switch. I believe MK sell pust to make switches. It must be possible to mount one in the switch that I have.

CM.

[Lurch]

On Thu, 9 Dec 2004 14:33:27 -0000, "Al Reynolds" strung together this:

Nope, PTM is just that, push and it makes contact. Momentary is momentary, usually for as long as you're pushing the switch, in either the open or closed position.

If you keep the power button pushed on on the PC it's the mobo that ignores the signal after a couple of seconds rather than the switch becoming open circuit.

[Lurch]

On Thu, 9 Dec 2004 16:01:02 -0000, "Set Square" strung together this:

Look up 'direct on line starter', or 'DOL starter'. That's how they work.

[Tom]

Used to be classified as Case1. "Push to Make" "Release to break" (PTMRTB) and Case 2. "Push to Make" "Push to Break" (PTMPTB). Cheers Tom

[Lurch]

On Sat, 11 Dec 2004 17:08:05 -0000, "Tom" strung together this:

Or more simply, latching.

[Charles Middleton]

Thanks all for the information. Following on from this, can anyone explain what an "Intermediate" switch is? Thanks in advance, CM.

[BigWallop]

An "Intermediate" switch swaps, or switches between, the two interconnection conductors through a two way switching circuit, so turning it into a three way switching system.

[Colin Wilson]

It crosses over the cores like this, and is used to add a third (or more) switches to a two way circuit...

---o o--- \ . .\

---o \o---

The 's will be connected with the switch in one position, the .'s with the switch in the other

Forgive the crap ascii :-}

[Lurch]

On Mon, 13 Dec 2004 22:17:03 GMT, "BigWallop" strung together this:

Or as many as you want.

[Peter Stockdale]

Always willing to have a bash!! A switch that is in line with another switch to the appliance that will on/off the appliance as well. eg: - A desk lamp normally operated off/on by switch on lamp itself, plugged in to a switched socket. The switch on the latter is acting as an "intermediate" switch.

Pete

[BigWallop]

Don't confuse it any further. :-))