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Simple directional control switch

Simple directional control switch

Simple directional control switch

(OP)
Hello Everyone,

My son is building an electric motor for a science project. The circuit will also power an electromagnet and buzzer. He has a sliding rheostat to control the power to each component. He needs a simple directional control switch to direct the current from the battery to one component at a time. I've looked online but can't find anything suitable. I know this is an elementary request but I would appreciate any ideas.

RE: Simple directional control switch

Current and voltage? I can imagine very low, like in 12V battery power max?

If you want a rotary type switch mechanism, the search term you are looking for is a "selector switch". Common are 2 and 3 positions, less common are 4, then after that they get harder to find ready-made. But someone will build you anything you like if you describe it on the back of a large enough check. He must also decide if there needs to be an "Off" position so that no power goes anywhere, or not (if for instance there is a separate on-off switch). A few more details are necessary for more specific help.

You can get them at auto parts stores too, they will be the toggle switch type. So two positions, no Off would be a "Double Throw" switch, often abbreviated "DT", then you chose the number of distinct contacts, as in Sigle Pole (SP). or Double Pole (DP). So what you will see on the package will say SPST, DPST, DPDT, DPST, etc. if you want 3 positions, it is Triple Throw (TT), but there are also those with 2 positions plus a center Off, usually referred to as DT-CO. If you want three sets of contacts, each closed in only one position, it must say TPTT (Triple Pole Triple Throw).

"Will work for (the memory of) salami"

RE: Simple directional control switch

If you know a friendly scarp yard, many automobile heater switches will be suitable. A common type of heater control is a multiple position selector switch with series resistors across the switch terminals. For low speed, all the resistance is in the circuit. at each succeeding step, a resistor is bypassed until the last position where the full battery voltage is supplied to the fan motor with no resistance in the circuit.
Clip off the resistors and you have a multiple position selector switch good for 12 Volt battery use and a reasonable current rating for experimental use.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Simple directional control switch

Hmm.. the new relaxed style? School project, mechanical, no experience - see, it doesn't hurt that much.

But I think this was close.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Simple directional control switch

(OP)
Thanks for the ideas!! Glen

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