Relay coils wired backwards

[navdave]

Been a while since I've built a channel switching amp. Well accidentally wired my two relay coils backwards I can fix the problem but it will be a pretty big pain in the butt cause I used some epoxy to secure the power supply wires under the board. I'm using 5 V relays I bought from Doug and I know they have a + and - sign written on top of the relay. I could've sworn on a previous channel switcher I've built that I had them wired the exact same way I have them wire now and it worked fine.  Does it even matter which side is being used polarity wise for the power?

[sluckey]

It may not matter to the relay coil itself, but there is an onboard diode connected across the coil and it will require the positive voltage to be connected to the cathode.

[PRR]

Classic basic simple relays do not care.

5V relays aim at "logic chip" uses and "conveniently" add the kickback diode to simplify your work. If you get that backward, your 5V DC is pulled down to 0.6V at infinite current.

[navdave]

Yeah I wired everything correct it's just backwards from how Doug has in in his relay hook up page. I'll test it tonight and report the results.

Classic basic simple relays do not care.

5V relays aim at "logic chip" uses and "conveniently" add the kickback diode to simplify your work. If you get that backward, your 5V DC is pulled down to 0.6V at infinite current.

[navdave]

I opted out of using Doug's relay pcb's. Positive voltage hooked up on the left side negative on the right.

It may not matter to the relay coil itself, but there is an onboard diode connected across the coil and it will require the positive voltage to be connected to the cathode.

[sluckey]

Left, right, top, bottom... It's all relative to how you hold your mouth.    Do you mean like this? --->

[navdave]

Yessir and I realized this morning that I might of had it wrong because I was fallowing my layout I drew up about 9 years ago. As long as it works and I don't have to tear stuff all apart  I'm happy 😄

Left, right, top, bottom... It's all relative to how you hold your mouth.    Do you mean like this? --->

[navdave]

Well I have to redo it these relays will not work if wired backwards well you live you learn thanks for all the help!

[sluckey]

Did you try it with the diode disconnected?

[navdave]

Yessir first thing I did was remove the diodes across the relays and try again if you have these relays hooked up backwards they won't work.

Did you try it with the diode disconnected?

[pompeiisneaks]

as a totally separate aside, that resistor above the relay seems to have missed it's solder on the top turret, just FYI :)

It is a beautiful looking board though!

~Phil

[navdave]

Good eye they'll be soldered in when the board is being wired to the tubes and chassis.

as a totally separate aside, that resistor above the relay seems to have missed it's solder on the top turret, just FYI :)

It is a beautiful looking board though!

~Phil