relay NO is open no power between com and NO the NC is closed power between com and NC is there operate the relay the power between the NO & NC should swap if you have power between NO & com you have a bad relay or the NO &NC are swapped and if the relay does not operate check the power input

I will power the receiver from the ESC and hopefully all will be ok.
The battery and receiver were just to test the relay switch before I fitted it into the tug I am building.
Thanks again for all of your advice and wisdom, you have all taught me so much.👍

Les,
Graham is correct again. Most radio battery packs are realy designed and sufficient for powering the receiver and servos only. As soon as one adds more servos or, as in your case, relay switches, the battery pack becomes insufficient to satisfy the needs of the system.
A long time ago, in my first class on basic electrical systems, my teacher said,nad I paraphrase, "always start at the battery because 75% of the time, that is where the trouble is". A great lesson learned. 😀

Just an additional note. I am not sure if this applies here but if a separate battery to that running the ESC is being used, the negative of the switch units has to be connected to the negative of the main battery also.
Peter.

Hi Les,

Great that you have it working now. If you are planning to power your receiver from a separate battery, it would be worth using 5 cells rather than 4. If you are going to power the receiver through your ESC then check the voltage from the ESC to your receiver to make sure it’s over 5v. (From what I’ve seen, they are usually closer to 6v)

Graham93

Thank you so much to all of you fellow members who sent a message to help solve my relay problem, I have learnt so much!

The problem was my battery that was powering the receiver, it was below 5v and it would not power the relay on the relay switch to turn the bulb on.

I have fully charged the battery powering the receiver and the relay switch is working fine as you can see from the photos.

Thanks again to everyone who sent a message for all your help.

A picture is worth a thousand words (see picture).

If still having a problem connect the relay board to the receiver, match the SWITCH on the transmitter to the same channel on the receiver (depending on what you have, you might need to go through a transmitter setup routine). Do not connect your sound /smoke/light/whatever to the relay board yet.

Use an ohmmeter or continuity light. Going across the NO and C terminals the meter or light should indicate the circuit works when you flip the switch on the transmitter.

If this doesn't work, remove the relay board plug from the receiver and plug in a spare servo. Power on the system and flip the switch again to see if the servo moves.

If this fails it is likely the transmitter switch is not programmed to the correct channel and from there you need to go to the setup manual.

As for the receiver, your relay board specs are: Minimum input voltage from receiver: 5v DC, Maximum 10v DC.

Whatever you are powering, the relay board spec is Maximum relay throughput: DC14 volts / 20amp (which should be ample for most model boat accessories).

Lew

Good thought Graham.
I would also suggest checking the voltage required for the switch, if possible. I say this because on many current radio systems, the receiver side of things, are now designed to operate on from5 to 7.2 volts or more. My new BEC's are selectable to that range.
I have another thought. I have run into this situation, where a dedicated switch channel does not send a signal at the full range of signal width that is available on , say, proportional channels. If I recall correctly, a similar situation occurred with an electronic switch. I pulled many a hair, they weren't gray back then, and some how stumbled upon the answer when I plugged the switch into a proportional channel. Of course, that didn't work still, but when I added the trim button range, viola, the switch worked. I am not saying that this is the case here, but an option.
You may also have a bad relay, solder connection on the board, or many other possibilities.
With luck, your battery pack meeds charging. If you have a BEC that you caan power your receiver pack with, that may be worth a try as well.

I just had that thought myself, spooky!

I will charge the battery pack overnight and make sure I have enough volts.
🤞

Hi Les,

One more thought. Is your receiver battery fully charged? I notice that the specification for your relay switch states a minimum supply voltage of 5v. You are using a 4 cell battery. If it isn’t fully charged, it could be less than 5v and may not have enough power to operate the relay even though it is OK for the receiver.

Graham93

I have turned everything off and put it all away for today but I will set it up again tomorrow and see if I can get it working, thank you all for the help and advice.

I agree with Graham. However I do believe that the wiring to the switch is polarity sensitive so follow the very clear instructions that you posted earlier. I have had a similar problem with a Chinese unit so yours could be the same.
dave976

I am using a toggle on/off switch on my transmitter that works perfectly when a servo is attached, so not the switch.

Hi Les,

It’s getting tricky now!

Your Tx and Rx are working fine. I’ve looked at the description of your relay switches on eBay and there is no mention of them being momentary. From the description I would expect them to be on/off type.

Last thing to try and check is that your transmitter is outputting a standard 1-2ms pulse width. If the pulse doesn’t cover the full range, then the switch might not operate as it should. I would check this with an oscilloscope, but without one, you could try a different channel. Perhaps try plugging the relay switch into the throttle or rudder channel on the receiver to see if they will make the switch work.

Graham93

Are you using a momentary switch, or a self centering pot on the transmitter? This will give you a momentary action on the relay. Try using a toggle switch channel which is not a momentary type.

The relay should stay on or off depending the position of the transmitter switch.

Good luck

Tested the switch on my transmitter with a servo and the switch works fine

Yes I did, Thank you and I corrected it. Could this problem be due to a momentary module and one that is a dedicated ON/OFF type module?

I think you have a typo. The NO to Com are open when there is no input and the NC to Com are open when there is an input

Will try that now

Thank you

Hi Les,

The wiring looks OK now, except that you have the bulb wired to the NC on the switch. It should still work that way, although the lamp will be on with the switch not connected to the receiver, as you found.

I Think the next thing to try is to connect a servo to channel 5 on your receiver and check that it responds to the switch on your transmitter. The servo should travel from one end of its range to the other as you operate the switch.

If that doesn’t work, the problem is with your transmitter/receiver not with the relay switch.

Graham93

Thank you for all of the wiring advice

I connected the live from my battery to the COM on the relay switch and the live of the bulb to the NO side of the relay switch and then the negative of the bulb back to the battery and the lamp illuminated.

I connected the relay switch to channel 5 on my receiver and a red LED lit up on the relay switch.

I then used the flick switch which is channel 5 on my transmitter and it failed to switch the bulb on or off.

Just to make sure it wasn’t a broken switch on my transmitter, I changed the transmitter for another and the same thing happened.

Hi Les,

Your wiring is wrong. Try it this way:

1. Connect your power supply positive to COM.
2. Connect one side of the lamp to NO.
3. Connect the other side of the lamp to your power supply negative.

Enjoy!

Graham93

Thank you so much for the replies to my post.

I did an ohms test on the three terminals and got a bleep from the COM and NO so wired a bulb between the two.

When connected to a power supply the switch LED lit up.

The lamp stayed on permanently even when the switch on the transmitter was switched on and off, but the LED on the relay switch went off for a second and then came back on.

I tried again with the live to the COM and the bulb to the NC but this time the bulb remained unlit when the switch on the transmitter was switched on and off.

This happened on both of the relays that I have.

Am I doing something wrong or do you think that these are these switches duff?

The end with the connector fits into one of the receiver ports (your choice on what transmitter control you want to use). On the NO/COM/NC (relay) side this is jut the relay connections. The NO is normally open when the relay is not activated and the NC is Normally closed when the relay is not activated. Look at it like a switch. I would wire it up as a NO normally open and when the transmitter control is activated it will close the connection and activate the lights or smoke unit. If the lights and smoke units use the same voltage then you can wire it up so that both are activated at the same time. If you need to control the lights and smoke unit independently you will need two relay units. I would hook bench test the relay control out of a boat with the receiver and Ohm meter to check the connections and to learn about the relay control. These units do not cost that much on eBay as I just purchased 3 of them and will be using one for lights and another for the horn.

I do believe that the unit is series wired. It can be wired on the positive or negative side of the battery circuit. Personally, I would apply battery + to common, then it is your choice regarding whether you want the circuit to be normally on(closed) or open( off). Then when the switch is energized, the circuit respondes accordingly, ie, the circuit closes(turns on) or opens (turns off).

I have several of these (or a similar manufacturer). See photo for wiring info.
Lew