5v Relay board not working with external wall adapter

Hello Guys

i made a 4 channel relay board here is my schematic

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the relay board is working good with arduino 5v and gnd. while it was not working with extrnal wall adaptor pls some one explain me why is this happening to me ?

Make sure you have a common ground between the Arduino and the relay board.

DVDdoug: Make sure you have a common ground between the Arduino and the relay board.

In this case, all that means is that you need to connect arduino/power adapter ground, to the emitter of the transistor - those need to share common ground.

DrAzzy:
In this case, all that means is that you need to connect arduino/power adapter ground, to the emitter of the transistor - those need to share common ground.

My power adapter ground is connected to emitter of transistor still no luck

Make sure you have a common ground between the Arduino and the relay board.

That would only be necessary if he was using it to power the relay but he's not. It's only connected to the contacts of the relay. I think there might be something he isn't telling us because there is no connection between the external supply and the operation of the relay (coil).

the relay board is working good with arduino 5v and gnd. while it was not working with extrnal wall adaptor pls some one explain me why is this happening to me ?

Or put more directly, why in the world would he expect it to work with the wall adaptor since the wall adaptor power has nothing to do with the relay operation. I don't think we are going to get to the bottom of this until the OP posts a photo of his wiring or explains why he thinks it should work with a wall adaptor.

@OP, Are you plugging the wall adaptor into the arduino external dc power barreljack ? If so , what is the "supply" in the schematic that is powering the load ? (or is THAT the wall adaptor ?)

Why is "Vcc " not specified ?

raschemmel: That would only be necessary if he was using it to power the relay but he's not. It's only connected to the contacts of the relay. I think there might be something he isn't telling us because there is no connection between the external supply and the operation of the relay (coil).

Or put more directly, why in the world would he expect it to work with the wall adaptor since the wall adaptor power has nothing to do with the relay operation. I don't think we are going to get to the bottom of this until the OP posts a photo of his wiring or explains why he thinks it should work with a wall adaptor.

@OP, Are you plugging the wall adaptor into the arduino external dc power barreljack ? If so , what is the "supply" in the schematic that is powering the load ? (or is THAT the wall adaptor ?)

Why is "Vcc " not specified ?

no I am powering the relay board via 5v wall adaptor through power jack I connected the transistor emitter to ground of power jack. And 5v rail to coil of relay .

Note: I just gone through pinout of power jack there are three pin common, gnd and vcc .which pin i should connect to emmitter of transistor gnd or common pin ? Is there difference between gnd and common?

Vcc ? wall adaptor ? what is connected to Vcc when you use the wall adaptor ?

Use a meter to ohm out the power jack. Which power jack ? (arduino or relay board?) Do you have a schematic of the relay board ? Are you sure the logic circuitry on the board has power when you use the power jack ? Is there a jumper on the relay board to select logic power source ?

raschemmel: Vcc ? wall adaptor ? what is connected to Vcc when you use the wall adaptor ?

Use a meter to ohm out the power jack. Which power jack ? (arduino or relay board?) Do you have a schematic of the relay board ? Are you sure the logic circuitry on the board has power when you use the power jack ? Is there a jumper on the relay board to select logic power source ?

The relay board here I am using is home made .yes the circuit is working I tired by glowing led My vcc is coming from power jack which is connected to coil of relay .will post circuit photo as soon as I reach home