Some doubts about Right pins for connecting a Relay and Hc-05 To Arduino Uno R3 Board

Hey There I hope Everyone’s OK …
I hope i crated this topic at the right place and sorry if not :heart:
I have some doubts and beginner problems . you know i want to connect my Hc-05 Bluetooth and 4Ch Relay board to my Arduino …
Arduino is powered with a 12V Ac/Dc Adaptor …
i connect 5V and one of the Gnds on the left side of the board to bus strips in Bread Board .Then I Connect my Bluetooth pins to these on bread board ok ? … Then I wanna connect the Vcc and GND of the Relay board on this Bus strips… is it OK?? I really doubt it because its the same GND and 5V that is taken from Arduino board and there is more Gnds and a Vinn on Arduino board .(i don’t know much about Electricity and these stuff )
or I can connect relay directly to Arduino board through the other Gnd and Vin on Arduino ?
and is it ok i get the Power from Vin for 4 channel relay module?
at last i’m done with hc-05 module and powering it but this Relay module , I’m a bit confused about powering it up …
Sorry of the text became long … Thanks for your time !

You can use Fritzing to draw a simple wiring diagram. That is much easier to understand than text.
To your wiring: the arduino can take up to 12V and it converts it to down to 5V to provide a suitable voltage for many devices. You can use this 5V at the 5V pin. The Vin pin is used to give the arduino up to 12V, if you do not power it with plug-connector or via USB.
The HC-05 should be connected as in my diagram, but you can also use other pins for state and key.
As for the relay board, I dont know how yours looks like, so I can not tell you for sure, how to wire that. In general there is a logic-input-side of the relay and a power-switching-output side. The logic-input of the relay is connected to your arduino and the other side is connected to your application that you want to switch. But there I don’t know what you want to connect.

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Really Thanks for your answer
So I Don’t use Vin in my case …Thats Ok…

absolutely the logic-input-side ! I don’t Exactly know how to supply power for it’s function … This is My module
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It’s gonna be the 6 pins on left side i guess . In1-4 pins are ok …
about Vcc and Gnd ? So is it ok to connect them to that Buss that we made on Breadboard?
Sorry I couldn’t afford the software right now to draw it … i couldn’t find a trial version.
p.s:
Also i found this on the Official website just in case : “Vin is usually used to give input power, but since we are supplying 12V to Arduino using an adaptor, we can use Vin pin on Arduino to power the 12V relay module.”

And Also Can you tell me a bit about power-switching-output side? Thanks so much

Also i found this on the Official website just in case : “Vin is usually used to give input power, but since we are supplying 12V to Arduino using an adaptor, we can use Vin pin on Arduino to power the 12V relay module.”

You are right, the Vin pin is directly connected to the power jack. In your case it would have 12V.

You should not connect these 12V to Vcc of the relais, you can damage it that way.
But you may connect Vin to JDVcc on the right, if you remoce the jumper there. JDVcc is used to power the coils in the relais.
You can also use the jumper between Vcc and JDVcc and just connect 5V of Arduino to Vcc.

For the power-switching output (screw-connectors on top) you can read this website.

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OK, you have shown a 5 V module with the “SRD-5VDC-SL-C” relays.

This has nothing whatever to do with 12 V. Nor does the Arduino. “Vin” or the “barrel jack” on the UNO are useless for powering such an arrangement. If you want to know why, it is because the regulator on the UNO has no heatsink.

You need a 5 V supply to power it all. If the only component other than the UNO is the 4 channel relay board that draws 360 mA with all relays actuated, then you can connect a USB “phone charger” to the USB port and take the 5 V from the “5V” pin to power the relay board.

It would be better to connect regulated 5 V to the relay board and the “5V” pin and ground on the UNO except that you need to disconnect only the “5V” pin whenever you connect the USB port on a PC. If you only have 12 V, then you can use a switchmode “buck” regulator to provide 5 V from that.

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Thanks for Your time…
So 12V (Vin )is canceled and i totally get it now thanks to you guys…

you know this is the Scenerio :
There is The Arduino, a Hc05 bluetooth that must be active and this 5V relay … and I supply Arduino with a 12V Dc Adaptor All the time.
The Hc05 is connected to 5V and GND of Arduino and the 5V is Occupied . So is it ok that i connect The relay to that exact 5V and another GND of the board or not ?
ss
And by using only the selected ones not the crossed out ones…
and btw Arduino is connected to computer with usb sometimes for programming …
I’m a bit afraid that this power stuff may create some mess…

p.s:
So There is A 5V and a Gnd on the Breadboard that we connect from Arduino( So this becoms our power supply for Both Relay and Bluetooth) Correct me if i’m wrong please .
So if this is the answer…
I should connect all these and the data pins also and then Connect Arduino using a 12V dc adaptor . then I can also connect arduino to my laptop with USB? (no problem???)

You are making me nervous with your continued reference to a “12V DC Adaptor”. I presume whatever unspecified devices you are connecting to the relay contacts require 12 V, otherwise 12 V has nothing to do with the Arduino.

You need a 5 V supply. It could be a switchmode “buck” regulator to provide 5 V from that 12 V or it could be a separate 5 V regulated supply such as a USB “phone charger”. Whatever that 5 V supply is, you need to connect 5 V and ground directly from it by a pair of wires running together as a bundle to the “JD-VCC” and “GND” pins on the relay board as in the diagram in #5.

You also need to connect 5 V and ground directly from that 5 V power supply by a pair of wires running together as a bundle to the “5V” and “GND” pins on the UNO itself, having the option to disconnect only the “5V” pin whenever you connect the UNO to the USB port on a PC. This limitation would not apply if you were using the more practical Arduino (or clone) Nano,

And you connect the “IN” pins and “VCC” but not the “GND” pin on the relay board as a bundle, to the corresponding pins on the Arduino board.

Unfortunately with a UNO, it is not really practical to use a breadboard. Things are much easier with a Nano where you can prototype with a breadboard or use a “screw shield”.