Cobrapin Coils mixed-bank HV questions

[Ted Gaunt]

I'm using Cobrapin Controller and the docs say to match the coil source voltage up with the correct control sink bank A-to-HVA, B-to-HVB, etc.

I'm doing that generally, but for something like a solo coil on bank A, can it safely source from HV_B's power?  I assume so.  Trying to avoid running an extra line.  (same power used on all HV)

unrelated question2: can one run different voltages to different banks?  like HVA is 48V, and HVB is 12?

unrelated question3: using Corbapin Satellite, any reason not to run coils off this board?  I'm not talking about flippers/pops, but something simple like a saucer.  I figure that without the large Cap, it just has less power delivery, which is fine for stuff like that.

[Dan - aka BorgDog]

q1: i would assume that would be fine also, they are all connected to the same inputs

q2: I don't think thats possible on main cobra board, maybe put the other voltage on a satellite board?

q3: I have 6 chimes, a bell and a knocker running off my satellite board, works fine.  I did put a separate set of capacitors (old opp power filter board, pcb available from cobra) to feed the satellite, but cobra did tell me I could just pull from HVA or B or C if i wanted and it would work as well and include the cap.

[cobra18t]

You can technically do that, but be careful about fault conditions. Remember that HV_A and HV_B are not the same because fuses separate them. If you mix bank coils and blow the fuse in one bank for whatever reason, you could cause issues on the other bank or even blow a transistor or onboard diode if you do not have flyback diodes on your coils.

I would make sure to have flyback diodes on any coils on a mixed bank. Mixing the banks means you are violating the onboard protection and you cannot rely on it so you need to add your own. Same with adding a 12V flasher on a 48V bank, for example. You can power the flasher from a separate 12V supply, just make sure to add a flyback diode across the flasher. Whenever adding/including diodes, make sure the polarity is correct or again, you will burn a transistor.

I am happy to review any schematics you can show as a sanity check to reduce the risk of burning up parts.

[Ted Gaunt]

Thank you borgdog and Cobra18t.   that answers my questions!

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