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Smiler
23-03-2009, 07:35 PM
Or, how not to wire a relay board to a BOB
Or, Jeff's further adventures into the magical world of electrickery......

So, the boys have sorted me out with the 5v to 4.5v issue. Decision time, do I go out to the workshop in the cold and mill out a suitable holder for the laser, attach switch and cable etc. or do I stay in the warm, forget the switch and cable and use the 5v from my BOB and install this handy relay board I have sitting here.
I chose warmth and relay installation.

Wired it up as the books say, to the BOB's 12v and 5V outputs (both separate) switched on and.....success, green light comes on and I can manually operate the relays, brilliant.

Now I need to wire it into one of the outputs on the bob to operate it. Done. Switch on, FIIIIZZZZZZZZZZ, delay (short), BANG! BOB loses a transistor and a capacitor swells up like a sore thumb.

Board now back with Roy at DIY CNC( a real champ) for fixing and a replacement on it's way back up as a spare.

Thank God I never got around to installing those diodes, probably be missing one small island and half the west coast :p

Anyway I found out two things, I really do know just enough to be dangerous and my tagline is just soooo accurate.

Jeff.

No1_sonuk
23-03-2009, 11:21 PM
Now I need to wire it into one of the outputs on the bob to operate it. Done. Switch on, FIIIIZZZZZZZZZZ, delay (short), BANG! BOB loses a transistor and a capacitor swells up like a sore thumb.
Did the magic smoke escape too?

Smiler
23-03-2009, 11:37 PM
Did the magic smoke escape too?

Yes, that horrible acrid type that lingers for hours.:eek:

Funnily enough, Roy at DIY CNC was sure what I did was ok. Must have crossed a wire over somewhere :confused:

Jeff.

Lee Roberts
24-03-2009, 03:39 AM
......ops :)