Can't make an SSR module work properly. Need help with double-checking me.

Greetings! I need somebody double-check what I have. I'm really out of ideas.

  • I have purchased 2 modules of 2-channel SSR module (based on Omron G3MB-202P). They all were sealed. Package was not damaged.
  • I have connected 5v to DC+ and DC-. I was expecting that nothing's going to happen (because it's just power). Actual result was 2 LED started glowing red (like if the relay was turned on). I have measured voltage on the Omron module input (legs 3 and 4) and it was 1.79v.
  • When I have connected a simple 220v light bulb to the output, nothing happened.
  • If I set high (5v) to CH1 of the module, then the following happens: (1) corresponding LED stops glowing, or becomes very dim. (2) voltage on the Omron module input (legs 3 and 4) goes down to 1.14v. And obviously the relay stays closed.

If I bypass all the circuits of the module and connect 5v into the Omron relay (legs 3 and 4) then it opens successfully and my bulb turns on.

Am I connecting the entire module incorrectly? Maybe there are other owners of such a module?

Any info would be helpful!

Hi,
Welcome to the forum.

What are you using for the 5V supply?
Have you measured the supply voltage when you connect CH1 or CH2 to 5V?
Have you tried connecting CH1 or CH2 to gnd of the 5V supply?

Tom... :slight_smile:

Hi Tom. First of all, thank you for such a quick reply! And thanks for the picture. It looks like mine except mine has "High level trigger" written on it.

Let me reply one by one.

(1) What are you using for the 5V supply?
Different options were used. A breadboard power supply. And a 220v powered configurable (3v-12v) supply configured to 12v.
I did confirm the voltage. For the breadboard power supply it was 4.89v for the 220v powered one I have set it to exactly 5v (well, 5.02v per my multi-meter).

Now (2) Have you measured the supply voltage when you connect CH1 or CH2 to 5V?
It does not change. At least my multimeter it not able to detect that change. 5.02v

(3) Have you tried connecting CH1 or CH2 to gnd of the 5V supply?
voltage of the supply remains 5.02v
LED starts to glow brighter
Omron relay's voltage b/w 3 and 4 legs becomes 2.11v (not enough to light the bulb)

"And a 220v powered configurable (3v-12v) supply configured to 12v."
Does that mean that you, at some point, hit it with 12V?

runaway_pancake:
“And a 220v powered configurable (3v-12v) supply configured to 12v.”
Does that mean that you, at some point, hit it with 12V?

Negative. :slight_smile:

I set 5v first and then plug it in. The voltage controller there on that power supply is not easy to accidentally change so I’m pretty sure that no overvoltage was there.

https://forum.hobbycomponents.com/viewtopic.php?t=2156

You're not laying the lamps across the AC terminals of the board, right?

Line In (SSR In) on one terminal and the other gets a lamp lead. The other lamp lead goes to Neutral. Yes?

Perhaps upload a diagram of your layout.

runaway_pancake:
The other lamp lead goes to Neutral. Yes?

That's correct. The latter link from electronics.stackexchange.com is very much like mine circuit.

I have checked that the 220v wiring is correct by simply applying 5v to the Omron relay itself. When I do that, my bulb is turned on immediately with no problems. I can repeat that trick again and again. But I want to use the module.

It looks like there's no obvious mistake I'm making. Then maybe the hypothesis of having 2 faulty modules becomes not that unrealistic... :frowning:

Input switch voltage: 0V to 2.4V
Input release voltage: 3.5 to 5V

Remove the existing wire from CH1, connect one end of a jumper wire to CH1, with the other end, touch the +5V terminal, then the -5V terminal. What happens?

JCA34F:
Remove the existing wire from CH1, connect one end of a jumper wire to CH1, with the other end, touch the +5V terminal, then the -5V terminal. What happens?

Hi! If I get you right, you are proposing to connect CH1 with the +5v and GND of the power supply without any microcontroller. If so then this is what I was doing above.

Just in case, I'm attaching a picture.

I'd recommend to read my posts very carefully. You do not need to read all. The 1st one will be enough.

I say there

If I bypass all the circuits of the module and connect 5v into the Omron relay (legs 3 and 4) then it opens successfully and my bulb turns on.

. That one alone means that I know something about using the relays. But thanks for checking that. Even in such a... well... specific manned let's call it that way.

PS
I would not treat others as stupid :wink: helps to avoid awkward situations.

Draw your circuit on a blank sheet of printer
paper, take phoro nd upload it

Quote from lex016

It looks like I was really the lucky one to receive 2 faulty relays.

I have contacted another supplier and ordered a Low Level Trigger version of the same relay. Same Omron elements. All works fine.

So in case you see the same behavior - it's not you - it's relay that is broken.