Relay (high/low level trigger)

[Cheaps]

I bought a High/Low level trigger, don't know why anymore, but it's driving me nuts that I can't get it working.

My setup
1. Hardware = Wemos D1 Mini (powered by a micro usb cable and a decent power supply)
2. 4 relays module (hi / low level trigger)

My 5v and ground is connected to the Relays board, and the D7 (GPIO 13) is connected to the first signal of the relays board. The PWR led of the relay board is on!

When I trigger the LED via http cmd (http://192.168.1.25/control?cmd=GPIO,13,1) I see a LED shinging on the relays board, but I don't hear a switchting sound. I already tried a few other thing, (connect to 3V), buit all doesn't make sense. I'll try to add a picture, hopefully one of you has an idea, before I have to wait another month before I get some new (easyer) relays out of China.

[enesbcs]

My setup
1. Hardware = Wemos D1 Mini (powered by a micro usb cable and a decent power supply)
2. 4 relays module (hi / low level trigger)
My 5v and ground is connected to the Relays board, and the D7 (GPIO 13) is connected to the first signal of the relays board. The PWR led of the relay board is on!

Typical "5V relays on 3V3 controller" paradox. I am only buying 3V relays since i learned a few things about 5V relays.
1. If there are a separate JD-VCC pin on the relay board, supply it with 5V DC and connect 3V3 to the relay VCC from the D1 Mini, and you can control the relay board with normal GPIO
2. If there are no JD-VCC, than you can control it through some transistor, there are an example for an 1ch 5V relay here:
http://www.bambusekd.cz/dev/raspberry-control-5V-relay

[budman1758]

Looking at the picture on the right if you look closely at the actual relay you will see they are 12 volt relays. So the relays need 12 volts to trigger.
It MAY be possible to trigger them with 3.3 volts because they use opto-isolators but I would test that with a voltage source other than the ESP to test.
If they do not work that way then a transistor setup will need to be used. A ULN2803 Darlington array chip would work fine.