Chevy Astro and GMC Safari Forum banner
1 - 2 of 2 Posts

·
Registered
1998 LS AWD Forest Green metallic
Joined
·
1,324 Posts
Minor semantics issue...
A diode that is 'blown' usually means 'open circuit'.. That should not cause a short, to blow a fuse.
A diode can fail in a 'shorted' mode, and could cause a fuse to fail, but it is not nearly as common.
Rod J.
Issaquah, WA
 

·
Registered
1998 LS AWD Forest Green metallic
Joined
·
1,324 Posts
MM,
I will defer to you. I agree with most of what you are saying.
We use diodes regularly in industrial control circuitry on nearly all DC powered relay coils ( same principle as in the AC clutch circuit) .
A properly functioning diode in that circuit does need pass some small amount of current when the colapsing magnetic field creates a voltage spike, otherwise it could not do it's job of dampening the spike from the collapse of the magnetic field when the clutch is deactivated.
Sorry, I just don't like the word 'blow' in this context. Most folks think of a blown fuse when the term is used and that does not fit well with diode applications, being able to fail either open or shorted.
So if you say, "...when diodes fail (in this type of application, they typically short, so they conduct in both directions....), I think that is more easily understood...again it is just semantics.
Rod J
 
  • Like
Reactions: Mmusicman
1 - 2 of 2 Posts
Top