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Topic: Relay Malfunctions with Manual Override Switch (Read 4775 times) previous topic - next topic

geoffism00

I agree, its built in.

Wrong type of switch for an external manual override control as its only SPST. To externally bypass the Arduino and get manual ON/OFF control of the relay, DPDT type would be more adequate ... or SP3T with center OFF.
There is something awfully pretty about the ON - OFF toggle switch but that can be a detail for later. I found these ON-OFF-ON, if it works on off on doesn't bother me.


http://www.ebay.com/itm/10-Pieces-Momentary-Mini-Toggle-Switch-ON-OFF-ON-6-pin-12vdc-dpdt-1-4-A5-/252012557301?hash=item3aad1e73f5:g:us0AAOSwHnFVktAG

dlloyd

Yes, that could work. It depends on what you want.
This switch automatically returns to the center OFF position ... this could be the default position for software control.
Toggle up and hold it there to override and energize the relay.
Toggle down and hold it there to override and de-energize the relay.

The switch would need to be connected to the control side of the relay board, not the relay contact side. Does this meet with your expectations?

geoffism00

Yes, that could work. It depends on what you want.
This switch automatically returns to the center OFF position ... this could be the default position for software control.
Toggle up and hold it there to override and energize the relay.
Toggle down and hold it there to override and de-energize the relay.

The switch would need to be connected to the control side of the relay board, not the relay contact side. Does this meet with your expectations?

Let me explain what I'm doing. I have a fish tank, an ro system, etape water level sensor a 12v solenoid for the ro system to fill the tank and a 12v 1/2" solenoid for a gravity fed drain. Everything is driven by an sd card and Real Time Clock to keep track of the last time the drain was ran and the ro fills when the water level drops per the sensor.

Bad things happen, fish need to be removed and the tank needs to be drained manually so I can clean it. You have been such a big help I hate to ask but all these switch types are a bit confusing. Could you recommend a link to the switch I should have to manually run my drain solenoid. I don't think what I sent is it because some tanks go to 200+ and I cant stand there and hold the switch. ON OFF action would be best but I will take anything that works in a toggle that I can flip and walk away. I'm a disabled vet and can't stand up for very long.


Cheers

dlloyd

Do you only need it for manually draining the tank?

If so, then what about using the Arduino to monitor the status of a simple pushbutton. If pressed (even momentarily) this could trigger the drain solenoid for XXX seconds or whatever is needed.

Sorry ... have to go for now but will check back later.

Boardburner2

Why the ground wire on the toggle switch.
That will short Vin to ground when the switch is in the off position and the left relay is active.
Remove that ground wire. You don't need it.
Leo..
I thought that but on closer inspection of the fritzing diagram its not the case, difficult to interpret.

I thought it was short with the togge on though.

Boardburner2

#35
Mar 01, 2016, 06:19 pm Last Edit: Mar 01, 2016, 08:00 pm by Boardburner2
Too bad your relay module requires 5V for the relay coils and they're not the 12V type. There won't be enough
The solenoids require 12 v any way, and his link indicated 12 relays being used.

In that case all that is needed is a couple of transistors.

I am just vexed i cannot upload the circuit i drew. back ar 6

EDIT looking at his link the transistors look as though they are there anyway , so its just a case of sorting out his power supply arrangement.

Boardburner2

#36
Mar 01, 2016, 08:01 pm Last Edit: Mar 01, 2016, 08:03 pm by Boardburner2
Finally managed it , the transistors are assumed as they are clearly visible on the photo in the link the op provided here.

http://www.amazon.com/Channel-optocoupler-Compatible-Atomic-Market/dp/B00TMFVVG6/ref=sr_1_8?ie=UTF8&qid=1456782075&sr=8-8&keywords=2+channel+relay

dlloyd

#37
Mar 01, 2016, 08:47 pm Last Edit: Mar 01, 2016, 09:10 pm by dlloyd
Possibly something like this could work ... it uses geoffism00's existing components.

Note: No opto-isolation, may need small capacitance (0.1µF) in parallel with each diode.
Relay Board Jumper Removed

Boardburner2

I think his existing board may be opto isolated, if his relays are 12V his existing circuit will work fine, just needs to move one wire.

dlloyd

#39
Mar 01, 2016, 08:59 pm Last Edit: Mar 01, 2016, 09:06 pm by dlloyd
Ahh, I couldn't quite figure out the fritzing image. I guess the difference would be override in hardware vs override in software. The software version could actually be used to fill or drain and also provide timeout if needed.

geoffism00

One of these came in the mail so I replaced it with the below link and everything works now. The only thing thats strange is when I turn it on, the relay turns on long enough for the ball valve to open all the way and then closes again. Do I need to deactivate the relay in setup(){}?

dlloyd

#41
Mar 05, 2016, 04:33 am Last Edit: Mar 05, 2016, 04:34 am by dlloyd
If your relay board uses LOW level to activate a relay, then in setup, you could use something like this
Code: [Select]
 pinMode(relayIN1, INPUT_PULLUP);
 pinMode(relayIN1, OUTPUT);

or this
Code: [Select]
 digitalWrite (relayIN1, HIGH);
 pinMode(relayIN1, OUTPUT);

Both ways will make sure that when Arduno changes the pin to OUTPUT, it will default to HIGH which will ensure the relay stays off.

TomGeorge

#42
Mar 05, 2016, 01:10 pm Last Edit: Mar 05, 2016, 01:10 pm by TomGeorge
Hi.
Looking at your fritzy diagram, what relay output terminals are you using to switch the solenoids?
It looks like COM and NC (Normally Closed)?
I would have thought COM and NO (Normally Open), so that activating the relay closes the circuit.

Tom...... :)

Everything runs on smoke, let the smoke out, it stops running....

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