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Need help with relays!

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i need a simple circuit diagram that will activate and deactivate a relay -(relay number 1).
negative side of the coil of relay 1 is always connected to the minus of the 12 v battery,
relay 2 will give plus from the battery to the positive side of the coil of relay 1 but only for 1 second and when that happens i want to keep relay 1 activated
and then when relay 2 gives again plus (for a second) to already activated relay 1 i want it to deactivate and to stay that way until again relay 2 gives plus and the hole process respites.
 
You need a relay flip-flop. Here are some ideas....
 
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Take care with the flip flop relay circuit, the characteristics of the relay itself are important, not all types work, I couldnt get it to work reliably.
 
Sounds like you are talking about a relay latching circuit. The first pulse latches a relay on and a second pulse turns the relay off. As mentioned, a good way to go about this is to use a flip flop circuit. You may want to look at the data sheet for a CD4013 D Flip Flop. Configure the 4013 as a divide by two counter. Take the Q out and use it to drive a transistor (PNP) to turn your relay on and off. Something you need to watch is when using relay contacts as a switch or any push button mechanical switch is what is called "Switch Bounce".

Why use two relays? You also don't mention what the relays will be switching as in voltage and current? How large are these relays as to coil current? You left out a considerable number of variables. Thus, you get a generic answer. Anyway, I would use a flip flop like the 4013 and clock it with your other relay or a push button switch.

Ron
 

Me too, pretty generic post. I also gave some thought to an impulse relay, pulse on and pulse off affair. I figure if the OP returns he can better define what exactly he wants to do. :)

Beats Me
Ron
 
i need it for 12 v car winch. i built the winch and i want it to work remotely, i already have a remote controller for it, that has 2 relays on it and they works as a momentary switch, one of them will be used to turn on a bigger relay for 12v high current, and the other relay on the base of the remote is relay number 2 that will give 12 v for a second when i press a remote an i want it to turn on and off 2 bigger relays ( relay no 1 ) for changing the rotation direction of the 12v dc motor.

so, relay 2 will give plus from the battery to the positive side of the coil of relay 1 but only for 1 second and when that happens i want to keep relay 1 activated
and then when relay 2 gives again plus (for a second) to already activated relay 1 i want it to deactivate and to stay that way until again relay 2 gives plus and the hole process respites.

i don't want to buy nothing special expensive i have a lot of relays and i want to learn to build this my self because i will be needing this again for more projects.
 
it basically like this: when i push and release a switch i want relay 1 to activate and stay that way, until i again push and release the same switch i want relay 1 to deactivate and stay that way.
 
I think that I understand what you want to do.
But, I suggest that you re-consider the way this thing will work...

You push a button for half a second and the winch starts to pull, and continues to pull for ever
What if something goes wrong with the remote control?
What if you drop the remote control and it breaks?
What if someone is in the way of whatever is being pulled by the winch which is still pulling...
...and you cannot stop the winch? :eek:

I am sorry to be a "safety nazi" but if I understand correctly what you are trying to do, your system would be potentially dangerous.

JimB
 
I have to agree with Jim. Car/Truck winch control systems account for safety and typically use 2 to 4 solenoids because the winch draws considerable current, they also reverse polarity so the cable can be run out or drawn in. A Google of "truck winch circuit" will bring up countless designs of winch control circuits. I assume you have the actual winch control and just want to add a remote circuit to control it? Should that be the case a drawing of the existing control circuit would be required to design a remote for it.

Doing what you initially posted is a relatively easy task. Using a relay latching circuit to correctly control a winch involves a bit more. Many winch circuits, just like overhead crane circuits also include limit switches.

Ron
 
I think that I understand what you want to do.
But, I suggest that you re-consider the way this thing will work...

You push a button for half a second and the winch starts to pull, and continues to pull for ever
What if something goes wrong with the remote control?
What if you drop the remote control and it breaks?
What if someone is in the way of whatever is being pulled by the winch which is still pulling...
...and you cannot stop the winch? :eek:

I am sorry to be a "safety nazi" but if I understand correctly what you are trying to do, your system would be potentially dangerous.

JimB

you didn't understand the way it works, let me explain:
i built the winch my self, and on the remote controller has two buttons for two relays relay 1 and relay 2 - winch both acts as a momentary switch
relay 1 will be used to pull/release but not for ever it will pull/release as long as i am holding button 1.
relay 2 will switch between pull and release i need this relay latching circuit for relay number 2 so it works like this: Touch it, it pulls, touch it again switches to release

and when i need to pull or release i use relay 1 to start/stop so when button 1 is released or something goes wrong it stops pulling or releasing, and i will be adding a safety switch that cuts power to everything. so its pretty safe.

can i have now relay circuit that i need please ?
 
i found this circuit:
one-button-toggle-relay-gif.51420

only i dont have 2n2222 i have only 2n3904
Can 2n3904 work in this case or if not which would be a good replacement?
 
So you have non-latching relays that function as NOT ENABLE and DIRECTION?

You want a single ON/OFF push button to:

1. Just control on/off by toggling?
2. Add direcion changing to 1 at each press?

Your working on protections?

Do you care about quiesent current?

Aside:

One controller I've thought about, but not for winches would operate as follows:
a) tap when stopped- turns on in "next direction"
b) double tap when stopped- turns on in opposite of next direction unless at limit.

c) single tap while moving - stops
d) double tap while moving stops and changes direction

Limits stop and set opposite direction
 
Can 2n3904 work in this case
Maybe. It would depend on your relay spec. What is the relay coil voltage and current rating?
 
you didn't understand the way it works, let me explain:
OK, it looks a though I did mis-understand the operation of your winch.

As for a relay circuit, did you look at those which MikeML linked to in post #2 ??

JimB
 
The 2n2222 and 2n3904 are often used interchangeable for general purpose transistors. The BIG difference is the 2n2222 has an absolule max collector current of 1A and the 2n3904 is 200 mA, The coil current is the determining factor.

The coil resistance is probably 90 ohms or about 151 mA at 13.6V , The 2n2222 is probably a better choice, but the 2n3904 will likely work.
 
I would use a circuit along these lines:

Image4.png




V1 is simulating the button push. R1, R2, D1 and C1 take care of switch bounce which I mentioned earlier. R3 simulates the relay coil and D2 acts as a flyback diode to surpress the spikes when the relay coil is deenergized and the field collapses, a 1N4002 will work. Q2 is a common 2N2907 transistor which turns the relay On and Off. V2 is 12 volt power which can be 12 to 14.5 automotive power. I would use a decoupling .1 uF capacitor on the power pin of U1 (power pin not shown). This circuit is rough but should do what you want. Remove V1 and put a normally open push button between Vin and 12 volts. I used a PNP transistor to make switching the high side easier as you mentioned high side switching.

The outputs look like this:
Image3.png


There are other ways to go about it but I would just use a common D flip flop circuit built around a CD4013 or equivalent. The parts can likely be had at Radio Shack or smilar retailer.

Ron
 
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It will be simpler, easier, and more reliable to use a toggle, rocker, or slide switch to control the direction. Then you can tell in glance which direction the winch is supposed to turn. With a push button arrangement you have to remember and hope the flip-flop does. The circuit I had in mind would include parts to reduce false triggering, but no flip-flop is 100% reliable, least of all connected to relays and motors. It may be cooler, but all around a worse way to do it.
 
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