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Help wiring a toggle switch?? Answered

Hi there, i need some advice on how to wire a toggle switch between a battery voltage monitor and a battery so that I can switch the monitor on and off as required.
My problem is that i need to pass 4 seperate wires through the toggle switch however I do not know enough about how a toggle switch works to achieve this.

Here is a video that shows what I am trying to achieve; http://www.youtube.com/watch?v=YPLNywzmnAk&feature=feedlik

This is a voltage monitor for a lithium polymer battery for use on an Airsoft Electric Gun (AEG)
the battery is stored inside a plastic box ,which is shown below, and i would like to insert the voltage monitor inside the plastic box with a toggle switch for turining it on and off

I have some pictures attached to show what exactly it is I am using and to hopefully explain more clearly.

Any advice at all would be greatly appreciated as I am at a loss about how to approach this.


The real question is, what do each other those wires do?

I'm assuming two of them power the monitor, while the other two are the voltages TO monitor.

since monitoring voltage is done by parallel wiring, simply cutting the power to the monitor should be enough.

So with a normal switch, you'll have 3 pins (- - -),
the switch at one position will bridge first 2 pins (+ + -),
and at the other position bridge the the last 2 pins.(- + +)

for OFF simply leave the unshared pin (the third one) disconnected and insulated.

Hi oreojdr, thanks for the reply.
There are 4 pins in use however, im assuming that one is powering the display and the other 3 pins are for each of the 3 cells in the battery, 1 pin per cell.
If there was a toggle switch with 4 connection pins i think what you are saying might do the trick. I do not know however if such switches exist.

The 4 pins are most likely (i'm about 90%) sure for power(red) and ground(black), then + and - for the ENTIRE battery. (blue and yellow, not sure which is which)

There is no need to measure each cell, AND you need two wires per connection when dealing with power.

Like gmoon and I were trying to say, simply cutting power to the voltage monitor should do the trick. You can do this by just cutting the red cable(make sure to test to see which cable is power, since i'm only 90% sure) and putting the switch there or if you can find connectors, put something between the original 4 pin connector and your monitor (preferred method)

If you want to know why/how it measures to the voltage, a quick wiki search will probably give you answers. The quick and dirty is voltage can be measured parallel to the circuit/battery. Connections in parallel have the same voltage just different currents (like gmoon said, the monitor will draw almost no load).

also, in your picture of switches, the top right one is all you need, a simple 3 pin switch (which means it has two positions), I used a similar switch the other day to modify my old mp3 player's USB cord so it could charge the player without trying to make a connection to the PC

Ok I went and got a 3 pole toggle switch and gave it a go by attaching the red,black and blue up to the toggle switch and then to the monitor, i wired the yellow directly from the battery to the monitor. The reason I connected the red,black and blue to the toggle was because while i was just holding wired to the battery and monitor to test what each wire done it seemed that blue and red both acted as the power wire so i thoight that if i put all 3 through the toggle switch it would definately work... I was wrong, whether it was down to my shoddy soldering or what, i dont know but when I had everything hooked up and i connected the battery... POOF!!! the whole thing went up in sparks and smoke!! so after almost setting my appartment carpet on fire, destroying a $25 battery and spending almost $50 on stuff to get the job done I have decided that while being unemployed I cannot afford to try again. Thanks for all of the ideas tho!! :) (maybe I should study a bit more before messing with this kind of stuff)

omg.. no no no..

if you didn't understand anything we said, you should of asked before doing something like that.

all you had to do was take the red (most likely) wire, cut it. hook it up the middle pin of your switch. take the other end and hook it to either side pin. then wrap the last pin in electrical tape.

the end.

you shorted both power pins and a "data" pin all together.

the switch connects whatever its hooked up to.
like i said earlier

So with a normal switch, you'll have 3 pins (- - -),
the switch at one position will bridge first 2 pins (+ + -),
and at the other position bridge the the last 2 pins.(- + +)

bridge = connect.

hi its griteck i would conect a switch between the red wire and its conector on the board because most of the time red means + toysdownunder.com has every thing you need

From Griteck

thanks griteck im going to give that approach a go and see how things go. Ill let ye know how it goes, cheers.


7 years ago

How about a link to a schematic or datasheet of the voltage monitor? We'd be able to help you better with that info.

In all likelihood, simply switching off either the power (or the ground) to the module will do the trick.

The ADC or whatever is sampling the voltage probably has a REALLY high input impedance--most ADCs do, or they would place a load on whatever they sample, which would effect the sampling process itself. So it shouldn't require breaking the connection to the batteries.

hi gmoon unfortunately i cannot find a schematic of the monitor but i like the idea of just switching off the power supply pin, that should do the trick. I get what you mean about how the monitor drains very little power but the reason I want to be able to turn off the monitor is because its actually quite bright and i wouldnt like to draw too much attention to myself during a night time wargame.