Relay wiring and configuration to Pixhawk

Hello All,
I want connect relay to RC5 or RC6, single relay.
I tried all way reading from this forum nothing helped me.
Can any one share wiring of relay to Pixhawk and what configuration is need?

This isn’t definitive. What RC Input channel do you want to use for control and what Aux output channel on the Pixhawk are you connecting the relay to?

The Wiki covers it well particularly for the Pixhawk:

@dkemxr Thanks for reply, yes I followed it but not working, can you share wiring diagram, is signal give high low voltage to control relay?

Output from the Aux ports is 3.3V when it’s activated. So the most common problem is not having a 3.3V coil relay.

Wiring diagram? It’s 2 wires, Ground and Signal from the Aux output you have configured. Let’s say you want Relay 1 out on Aux 5 from RC Chan 8.
BRD_PWM_COUNT 4 (so Aux 5&6 are available as GPIO)
RC8_OPTION 28 (Relay 1 On/off)
RELAY_PIN 54 (Relay 1 Aux 5)

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Yes I have made these setting, I did manually checked voltage of Aux 5, and could not get 3.3v i mean not even 1v.
Do we need to give external power to relay and only signal from Aux 5? I tried this, and found relay is always On.

No, the Aux output will power a 3.3V relay. Post your parameter file.

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Thanks, Yes I Could measure 3.3v between Signal and negative of Aux 5.
So, i need to use that signal 3.3v as IN(signal) to Relay having external power supply(Relay module)
Or have to use 3.3V relay and directly connect to relay coil.
Here is what i have to do

Then do it or buy one of these.

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@dkemxr Tons of thanks for your inputs, finally I could achieve with below circuit

The diode is missing in the diagram. Without it you can damage the transistor.

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