Unable to Power 8 Ch. Relay Board

Development Tools IDE 1.x
1

Devices:
ELEGOO 8 Channel DC 5V Relay Module with Optocoupler Compatibility
ESP32
5V 10A Mean Well LRS-50-5 Power Supply
and a 5V 2A phone charger or 5V 1A phone charger

I think this is my problem: When I check the voltage and amperage across my Ground and 3.3VIN pin on my ESP32, it reads 4.7V and 50-70mA.. I don't know what current the GPIO switches pull when turning on.

The voltage across the negative and positive leads of my 5V 10A PS is 4 something, and it's sparking, so it's pumping.

I've removed the jumper cable, connected the positive of my 5V 10A to the JD-VCC pin on the Relay, and the negative of that PS to the Ground of the Relay.

I've then connected the 3.3VIN to the VCC Pin on my Relay, and I get no indicator lights demonstrating that it's successfully powering the Relay.. I check the voltage across the VCC and the Ground, and there's nothing. I'm pretty sure there are indicator lights. I've never powered it on LOL, but ya.. no voltage.

I then attempted to connect the Ground of my ESP32 to the Ground of my Relay, and I have 4.7V across the Ground and VCC of the Relay now, and it reads 55mA.. Okay cool progress I guess.

So like I said, I'm pretty sure the issue is that my ESP32 isn't delivering enough amperage to the Relay board. It delivers the same amperage when running through the relay and when running through cables on a breadboard.

What the heck do I do?

I've attached a picture of my setup if it isn't clear. I have however started connecting the ESP32 and the Relay's grounds, because that's the only way I've gotten ANY voltage across the Relay's GD and VCC pins.

IMG_20210920_165648
IMG_20210920_1656481920×1440 336 KB

2

This is not good, should be 5v, sparking is bad, you must have a short.
Fix this before you go further.

4.7v on the relay Vcc terminal to Arduino GND is fine.

What happens when you take an INx terminal to ARDUINO GND .

3

I tested the voltage but not the amperage on the 5V 10A supply, because I assumed the amperage was ample due to the leads sparking when connected. The voltage is ~ 5V.

What should I expect across the InX terminal of the Relay and the Ground of the Arduino? I'll check voltage, amperage, continuity etc when I get home.

I'm truly lost lol.

Thanks for the time and input my friend.

4

Stop.

With the external 5v supply connected to the JDVcc pin and to relay board GND what is the voltage on the external supply ?

EDIT

With the Arduino 5v pin going to the relay board Vcc terminal, what is the voltage on the Arduino 5v pin to the Arduino GND ?

5

From the image, it looks the ESP32's CLK pin is connected to the VCC pin of the relay board. Did you mean to connect the relay VCC to the ESP32's 5V pin? Which would not be a good idea but that's your thing.

6

The relay board is sitting on a conductive bag. I suggest you remove the bag.

7

ESD bags are actually two layers of mylar plastic with outer side of the inner layer aluminized for conductivity. The inside and the outside of ESD bags are not conductive. We put returned boards on their ESD bags all the time for testing and debugging.
Paul

8

Given the sparking and what seems to be proper wiring I was thinking some of the bottom leads might be piercing the bag.

My motto has been, " then all the possible causes are ruled then start on the impossible causes "

9

Do people still use through-hole components?!!!1
Paul

10

Yes, don’t throw anything away. . . . .

image

1 Like
11

Relays, headers and terminal strips........

12

All surface mount, now days.
Yes, I still use Thru-hole stuff for projects.
Paul

13

But then it will scratch the table!

1 Like
15

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.