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Hi Guys,

I have a rocker switch from ebay: http://www.ebay.com/itm/110682551682?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 but the problem is that theres no information on how to hook it up. I asked the seller and he didn't know himself. Here's what the listing says:

DPST Operation
Size 1 1/4 inch hi  x  1 inch wide  x 1 3/8  deep
Lug type terminals
Built in light (light lits when switch is in the on position).
Marked on the rocker: I/O (on off) for precise indications
Rated at 15A 250V AC (20A 125V)
Snaps in to a rectangular hole
Panel mount
Long life

My problem is that the rocker switch has 4 terminals. I'm assuming 2 terminals for the mains, and 2 for the light bulb inside. How do I know which one is which, or can I assume that the light bulb inside is also 110 volts?

Thanks!!!!
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Massachusetts, USA
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DPST means Double Pole, Single Throw.

Double Pole means that there are two separate switches.  Typically if you look at the axis of motion the terinals on one side of the axis will be one switch and the terminal on the other side will be the other switch.

Single Throw means that the two switches are either ON or OFF.

The lamp should be suitable for 110 to 250 volts.

Assuming two terminals are near the middle of the switch and two are near one end I would expect the middle ones to be the inputs and the end ones to be the outputs.  I would further expect the lamp to be connected to the outputs so if you wire in reverse (power in the outputs and out the inputs) the lamp would be on all the time.
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Left Coast, CA (USA)
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Actually what you have there in not really well defined. If it's truly a DPST switch then how does the internal light get powered when in the on position. Why is there no voltage/current rating for the internal lamp stated?

I suspect it might just be a SPST switch for the user and the other two terminals are wired in series to the internal lamp. Without a datasheet this switch is pretty useless at best and possible dangerous at worst. If you have a multimeter you might be able to figure it out with an ohm meter looking for simple open and closed resistance value for contacts in one of the pole positions and looking for open and lamp resistance in the other pole position.

 It's quite possible that the lens cover is designed to be pulled straight off to gain access to the lamp for replacement? That might give you more information about the bulb voltage and current rating and even how it's wired to the user terminals.

If you are planning on using this switch in 120vac circuits, do please figure out the switch configuration 100% before applying power to the circuit.


Lefty

 
« Last Edit: December 12, 2012, 10:26:33 am by retrolefty » Logged

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That is a DPST switch, and I wouldn't expect it to be rated for 120VAC like it says because it looks too much like a 12V switch. the rating should be on the switch casing somewhere.

Anyway for wiring, DO NOT put black on one side and red on the other. you need to wire your power IN to one of the center blades, and then run the power OUT of the other blade on the same side.

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That is a DPST switch, and I wouldn't expect it to be rated for 120VAC like it says because it looks too much like a 12V switch. the rating should be on the switch casing somewhere.

Anyway for wiring, DO NOT put black on one side and red on the other. you need to wire your power IN to one of the center blades, and then run the power OUT of the other blade on the same side.



It only has four blades, what do you mean by 'center blades'? And it's impossible to tell if a switch's contacts are rated for just AC or DC or both by looking at a picture of it. A datasheet is required to tell what this animal really is.

Lefty
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