G120TH/FEZCobra III GIO driving DC3/3.3V Relay Module

NETMF & Gadgeteer
1

Hi,

has anybody used this 3/3.3.V relay module with G120TH or FEZ Cobra III. This is from China and they claim that it can be used with arduino…

I have not been able to dig out how much current it draws when it is controlled. Limitation is 4 mA per one output og G120 as far I understand.

The link:

http://www.ebay.com/itm/DC-3V-3-3V-Relay-High-Level-Driver-Relay-Module-Module-optocouplefor-Arduino-br-/221887500776?hash=item33a98691e8:g:5JMAAOSwgZ1XqUiT

2

You don’t need a high current from the G120 GPIO pin as it will drive the TTL input.The relay board has a separate input for DC power for the relay.

Connect GND of the G120 and 3.3V from the G120 or use a separate supply. The regulator on the Cobra 3 board should be able to handle min 1 relay.

Connect the GPIO pin to the IN input and now you can switch it on and off.

Reverse engineering the design using the relay part number funds your data for the relay operating current. At 3V this is 120mA

http://rabbitmax.com/files/SONGLE-SRD-05VDC-SL-C.pdf

1 Like
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I should add that you won’t have the isolation with this board even though it states that it uses an opto-coupler. This is because there is no separate ground for the INPUT and power. They are common.

3 Likes
4

Hi Dave,

thank you a lot … nice deep analytic answer.

Regards

Jari