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Looking for a DPST

cybrfire

cybrfire

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momentary push button.

Nothing from my usual suppliers and so far have only found stainless steel bodied buttons. I'd prefer something in black to closer match the carling switches.

A LED lighted center or ring around the center would be nice.

I know a few of you guys have done some pretty extensive searching for electronics. Anybody have a line on something like this?

I've checked the usual places. delcity, waytek and so on.

This is as close as I have gotten however, this one is 1, NO and 1 NC. I need both normally open.

http://www.amazon.com/uxcell®-Light...9&sr=8-77&keywords=DPST+momentary+push+button
 
I'm somewhat confused. You are looking for BOTH sides of a single throw ,momentary switch to have normally open contacts?
Am I correct that you want 2 separate circuits to activate when you push the switch?
That sounds like a relay situation to me, but I am sure that I don't understand what you are up to.
 
I think You understand the circuit just fine. One button activates two circuits separately. so, press the button and make two connections at the same time that are isolated from one another.

Maybe I need to do it with a relay...
 
Try modifying your search. Go for a DPDT spring loaded, and just use the terminals you want. They are a lot more common than what you are trying to find.

These places are my first places to look.

http://www.alliedelec.com/

http://www.digikey.com/

You might post a picture of what you have now, I found Carling switches on those sites, but don't know what you are trying to match.
 
Not trying to match anything exactly. This is for my truck build.

Its for the windshield wipers/washer. When you hit the washer pump the low side of the wipers should activate until the button is released. Then the normal park switch for the motor would complete the stroke.
 
http://www.alliedelec.com/

Found a few on that site but with the amperage ratings they carry it would have to be done with relays. Guess I need to start over and draw a new diagram.
 
Well, thats a little more tricky, but here are some ideas.

The PV4 series here looks promising. Except its metal.
https://www.e-switch.com/product-catalog/illuminated#.VtPbauZBmi8

And, if this link works, here are a few at Digikey.

http://www.digikey.com/product-sear...t=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

One problem I see, is that a lot of them are fairly low current rated. You may want to go with a relay just in case. Not sure how much current the wiper draws, but its probably more than 2 amps.
 
I found some but all low amperage and not sure I can design the circuit without the momentary button either way. DPDT with 2 normally open contacts would work. Still have to run the load through relays because I'm not finding anything that is high enough amperage ratings. Most of the buttons are designed for smaller control voltage/amperages.

So, if I can find a black, attractive, preferably LED lighted momentary push button DPDT with two normally open contacts, I think I'd be in business.

I have a delay module to wire into this as well. It is designed to work with the HI/LO grounded wiper motor. It wires in to the low side as well. A factory switch that is designed for the job would be much easier, just not gona work in my panel. Not to say I've looked at every factory switch available, I just have to doubt it.
 
I think I understand what you are trying to do.
Got a suggestion.
Two relays. Each one activated by one side of the switch. One relay is for the washer. It stays on as long as you hold the button. The other is the wiper motor. It also comes on when you hit the button, but there is a delay-on-break timer inline.
When you put power to the timer, it passes it to the relay and the wiper turns on immediately. When you release the button, the timer keeps the wiper going for a set length of time to finish clearing the water.

I was going to suggest using one of the little delay-on-break bricks I have used in the past for many projects. Cheap, wide range of voltages and very reliable. There is a whole line of them and they work great.
They are made by ICM, and are available in many configurations.
Here is their website.
http://www.icmcontrols.com/TIME-DELAY-RELAYS-DELAY-ON-BREAK-DOB-Prodlist.html

BUT, it turns out they are for 18-30 or 18-240VAC. I never gave it much thought, since I was working with either line voltage or control voltage. So, they will not work for your application.
Some quick searching turned up several 12vdc ones.
This one looks promising.

http://www.amazon.com/Timer-Delay-R..._UL160_SR120,160_&refRID=0JESAK8RC0H1V5R4BSX3

Hope this helps.
 
If you got time fordum, could you draw up a diagram of that configuration?

Everytime I draw it up I end up with the pump running everytime I use the low side wipers.
 
Yeah, DPDT works just as well as DPST, you just don't connect to all the terminals. If you go with relays, your push-button can be SPST or SPDT.

For the wipers, you just need an on/0ff switch, but controlling the wipers through a relay makes the logic work better for this. Running wiper motor current through the park switch will wear it out faster. So the wiper on/off switch goes in parallel to the park switch, so that whenever the wipers are turned off they return to park before stopping. Then your washer push-button controls the washer relay, but also has a diode to the wiper relay. So anytime the push the washer button, the wiper does at least one full wipe.

A delay of 5 seconds or so would be better, but optional.
 
cybrfire said:
If you got time fordum, could you draw up a diagram of that configuration?

Everytime I draw it up I end up with the pump running everytime I use the low side wipers.
Click to expand...
Yep, I'm tied up this morning, but I'll post something this afternoon.
 
OK, appreciate it. Still working on another circuit design using 3 relays. Might be able to make a single pole single throw work with 3 relays.
 
Blue85 said:
Yeah, DPDT works just as well as DPST, you just don't connect to all the terminals. If you go with relays, your push-button can be SPST or SPDT.

For the wipers, you just need an on/0ff switch, but controlling the wipers through a relay makes the logic work better for this. Running wiper motor current through the park switch will wear it out faster. So the wiper on/off switch goes in parallel to the park switch, so that whenever the wipers are turned off they return to park before stopping. Then your washer push-button controls the washer relay, but also has a diode to the wiper relay. So anytime the push the washer button, the wiper does at least one full wipe.

A delay of 5 seconds or so would be better, but optional.
Click to expand...

Missed your post Blue. Unfortunately I can't find any attractive buttons with DPDT either. Ive been trying to design the thing with a SPST and relays and cant quite get it right.

Unless I'm reading the factory schematic wrong, it would appear their wiper switch is and ON-ON-ON switch or a triple throw single pole. they have a ground supplied to the wiper via all three poles. One going to the park switch and the other two to the lo and hi respectively. So, when you shut the motor "off" technically you are supplying a ground to the park switch which completes the cycle and mechanically disconnects via a cammed disconnect inside the motor. If that's the case, why could the park switch not be grounded all the time. It should still disconnect when the cam comes around. IF that works out the wiper switch is a simple single pole double throw which you can get in a contura type rocker. That's what I'd like to use.

As far as the delay goes, I think that is what fordum's piece does. keeps things going for just a tad longer than once you let up. Optional but intriguing. The park switch will still bring it around that last time but it'd be nice to make one more pass with the wipers.
 
cybrfire said:
If you got time fordum, could you draw up a diagram of that configuration?

Everytime I draw it up I end up with the pump running everytime I use the low side wipers.
Click to expand...


OK, this schematic sucks. I did not have my regular software on this new computer, and had to download whatever I found for free.
Its small, but hopefully you can enlarge it. The library for this drawing software did not have a double pole single throw switch, so I drew two switches. Just realize that they are one switch.
And I was both in a hurry and eating supper with the other hand, so I cheated and just stuck in 12volt inputs and grounds wherever needed instead of tying them all to one point.
If its too small, or not clear, let me know and I will improve it.
Also if there is something you don't understand. Its not real obvious what I am doing. And I left out the regular wiper switch and the high speed setting entirelywiper1.jpg .
 
I think I got it with three relays and a SPST. actually 4 relays if you count the single for the Hi side of the wiper motor. How well does a relay work as an isolator between two circuits?
 
If done properly, its a total isolator. As you can see from my schematic, the washer pump and the wiper motor have no idea whether the other is on or not But you have to be sure that you do not fire two relays at the same time when you don't want to.
With my setup, all you have to add is a third relay for the high speed, since the low speed from the regular wiper switch turns on the same low speed relay on the other side of the timer.
However, just to be on the safe side, you should use a double throw relay for the high side, and let the power for the wash button come off the NC side of the high speed relay.
That way, if the wipers are on high, and you press the wash button, it will be dead because the high speed relay is pulled in and the NC is open. That way you cannot turn on the high and low speed windings at the same time.

Actually, you need to just kill the wiper part of the switch. By using a second contact on the high speed relay and break the line between the switch and the timer.
That way, you can hit the wash button when in high, and the washer would come on but the low speed would not get powered and the wipers would stay on high.
 
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