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Old 26-01-2020, 09:10   #1
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What type of switch do I need?

I have 3 wires. Two positives one negative. I'm looking for a button/switch that then I press it, connects all 3 together then disconnects when I remove pressure.

None of the 3 wires should

What type of button/switch do I need?
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Old 26-01-2020, 09:15   #2
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Re: What type of switch do I need?

I don't understand your question. It appears that you want to create a short circuit. Why?
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Old 26-01-2020, 10:00   #3
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Re: What type of switch do I need?

What Charlie said. Sounds like you want to create a short circuit. Maybe some additional information. Is the positive not connected to power, maybe trying to ground and discharge a capacitor or something like that?

And a question, "none of the three wires should" ...... what?
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Old 26-01-2020, 10:08   #4
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Re: What type of switch do I need?

That is what switches do right create a circuit by joining two wires together usually on the positive side.

I want one that can connect 3 wires when pushed. Rather than a traditional on/off switch that only connects/shorts/jumps two together.

It's not a short circuit though as the wires are running through and controlling a servo and a motor.

The use (doesn't really matter) in this case for an electric toilet. To have it bring water into the bowl and evacuate at the same time all 3 wires from the toilet must be shorted together.

The manufacture sells a separate switch for this function at nearly $200. All it's doing is jumping the 3 wires.

Quote:
Originally Posted by skipmac View Post

And a question, "none of the three wires should" ...... what?
That's a mistype but it's not possible to edit a post after a short time period.
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Old 26-01-2020, 10:26   #5
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Re: What type of switch do I need?

Couldn't you splice the two positives together away from the switch then just use a standard switch?
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Old 26-01-2020, 10:30   #6
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Re: What type of switch do I need?

A three pole single throw switch will perform this function, if the terminals ou the output poles are shorted together. A 3pst switch is what You need.
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Old 26-01-2020, 10:31   #7
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Re: What type of switch do I need?

The last thing you want to do is connect negative and positive. That will do nothing but create a short circuit, sparks, and a lot of heat.

Typically the only reason for a negative on a switch is for an indicator light. Switches connect positives.

Best to look at the schematic in the manual or buy the manufacturers intended switch.
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Old 26-01-2020, 10:33   #8
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Re: What type of switch do I need?

I was wondering the same as Basssears. But, if that doesn’t work for some reason you’re looking for a DPST (double pole single throw) switch. You can get these as toggle switches or buttons, momentary or maintained depending on your use. Check the current rating to make sure it matches the needs of both head devices.

With a DPST you basically have two switches side-by-side that operate together. For three wires you join the poles with a jumper on the side with one wire (presumably the one with the “negative” described above). Then connect each positive wire singly to the poles on the other side of the switch. Closing the switch will connect all three, opening it will isolate all three from each other.

In the US Digikey, Mouser, or Allied will have 10 to 20A switches in all styles for a few dollars. Higher current starts to get to be a bit scarcer and more expensive.

PS - if you can link to the head or their switch can then look up exact requirements and give you a more detailed recommendation.
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Old 26-01-2020, 10:35   #9
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Re: What type of switch do I need?

Quote:
Originally Posted by basssears View Post
Couldn't you splice the two positives together away from the switch then just use a standard switch?
One is a connecting the two positives (I suppose one is more a control wire than true positive) activates the servo and allows water to enter the toilet.

Adding the negative to the positive, operates the macerator.

The switch I have at the moment operates these two functions separately.

I was hoping I would pick up something from the local electronics store that would allow them to operate all together.

Quote:
Originally Posted by mitiempo View Post
The last thing you want to do is connect negative and positive. That will do nothing but create a short circuit, sparks, and a lot of heat.

Typically the only reason for a negative on a switch is for an indicator light. Switches connect positives.

Best to look at the schematic in the manual or buy the manufacturers intended switch.
Negative to positive operates the macerator. It runes through the motor. I've tested it.


Quote:
Originally Posted by lorenzoj View Post
A three pole single throw switch will perform this function, if the terminals ou the output poles are shorted together. A 3pst switch is what You need.
Brilliant. I'd looked at 3 pole switches, but they weren't single throw, that was what I was missing.

Thanks.

Sorry that my opening post wasn't as clear as needed. You know how it is when typing something as fast as possible wasn't in between jobs.
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Old 26-01-2020, 10:36   #10
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Re: What type of switch do I need?

You could use a DPST (Double Pole Single Throw) switch with the negative wire connected to one side of both poles.
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Old 26-01-2020, 10:37   #11
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Re: What type of switch do I need?

You can do it with a SPST Push Button Switch and 3 relays. Connect the input side of the relays, one to each of the 3 wires. Connect the output side of the 3 relays together. Connect power to one side of the SPST switch and other side to the 3 relays coils tied together and common to other side of relay coils tied together
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Old 26-01-2020, 10:46   #12
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Re: What type of switch do I need?

Quote:
Originally Posted by Dan Best View Post
You could use a DPST (Double Pole Single Throw) switch with the negative wire connected to one side of both poles.
Best Answer

The OP is not connecting two positives to ground, he's completing two circuits which control his toilet when the two leads are connected to ground. The circuits are being switched on the 'ground' side.
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Old 26-01-2020, 10:50   #13
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Re: What type of switch do I need?

Quote:
Originally Posted by guyrj33 View Post
Best Answer

The OP is not connecting two positives to ground, he's completing two circuits which control his toilet when the two leads are connected to ground. The circuits are being switched on the 'ground' side.
Now only to find it in rocker form or push button. Ideally rated up to 20a to eliminate the need for relays.

The manufacturer one is by Carling Technologies, but I couldn't see it in their catalogue.
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Old 26-01-2020, 10:54   #14
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Re: What type of switch do I need?

Some owners fit two separate switches to be able to control "flush" and "evacuate" independently so that you can easily control the water level. This is very useful when you are dealing with a blockage!

These Carling switches are suitable (rated 20A): https://www.amazon.com/CARLING-TECHN...detail-bullets

You need a 2-pole momentary action switch. Wire the 12v Positive to the two "input" terminals and connect the wires leading to the two pumps, one to each of the "output" terminals. You can check with a circuit tester which terminals are connected when you press the switch. If you want separate switches just use two of these switches - one for each pump. You could also use the single pole version of this switch, but the price difference will be small.
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Old 26-01-2020, 10:59   #15
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Re: What type of switch do I need?

Quote:
Originally Posted by mikedefieslife View Post
One is a connecting the two positives (I suppose one is more a control wire than true positive) activates the servo and allows water to enter the toilet.

Adding the negative to the positive, operates the macerator.

The switch I have at the moment operates these two functions separately.

I was hoping I would pick up something from the local electronics store that would allow them to operate all together.
If I understand this correctly, you want the servo and macerator to both work together when you operate a single switch/button? If this is the case, and will always be the case, then Basssears suggestion (post 5) should work.
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