not enough current for relays?

[Clive S]

24vdc 150W, but it seems its irrelevant for the outputs


seems it was never meant to do that, look bellow at specs from pdf. I wonder why sb will do such nice board, but that could not power an input of a bloody relay

I read that Boyan but it seem to indicate you can take out the 100R and then get 50mA what do you think. ..Clive

[Boyan Silyavski]

i read somewhere that the relays need more than that, ~80-100mA so at the end i bought the extra boards.

i wish sb simplified the stuff and said- " you need that board and that relay board or output board, cause otherwise you will not be able to do this and that " cause for me 50mA is like chinese.

how difficult would be to do that if you sell a product

[Clive S]

i read somewhere that the relays need more than that, ~80-100mA so at the end i bought the extra boards.

i wish sb simplified the stuff and said- " you need that board and that relay board or output board, cause otherwise you will not be able to do this and that " cause for me 50mA is like chinese.

how difficult would be to do that if you sell a product

I think a lot of small relays will switch at about 15mA https://www.sparkfun.com/products/100 or even less

[Boyan Silyavski]

Did not think of switching them directly.

Now i read that the relays i was going to use are triggered only by 5mA, so why would they not work?

By the way it looks a really quality stuff. and has LOW HIGH jumperson each pin. I have used it before with great success


Module Description :
1, the module uses genuine quality relay , normally open interfaces Maximum load : AC 250V/10A, DC 30V/10A;
2, using SMD optocoupler isolation , driving ability , stable performance ; trigger current 5mA;
3, the module voltage : 5V
4 , each way module can be set high or low triggered by jumper ;
5 , fault-tolerant design , even if the control line is broken , the relay will not operate ;
6 , the power indicator ( green ) , 8 relay status indicator ( red )
7 , interface design humane, all interfaces can be connected directly via terminal wiring leads , very convenient
8 , Module size : 141.5mm * 50mm * 18.5mm ( L * W * H )
9 , has four mounting bolts holes , hole 3.1mm, pitch 136mm * 44.5mm

[Clive S]

Did not think of switching them directly.

Now i read that the relays i was going to use are triggered only by 5mA, so why would they not work?

You would have to show how you are connecting them . It could be a problem in the way you are grounding them.

[HankMcSpank]

I have one of those relay boards (or at least one that looks remarkably like it) - I drive it directly with the 5V out from a CNCUSB Mk2/9 board digital output - no issues.

I'd measure the DC resistance of your relay coil...I'd wager you can probably short out that output 100 Ohm resistor (which should then see sufficient current to energize the relay) ...else play on the safe side & put something like a 10 ohm resistor across it (i.e. in parallel with it)

[cropwell]

You may have a faulty board. Try hooking it up to a 5v power supply and see if you get a relay operating with 5v from the same supply. Some boards I have switch the relay on with 0v and off with 5v. Also check the jumpers.