BALLAST RESISTOR........WHAT GIVES?

[rklein383]

My no longer a resistor.

 

[Dana67Dart]

Have you looked at the backside of a ballast resistor?

Definition: A mixture of coarse and fine aggregate...

Obviously the correct define. It just has a few extra wires attached to it

Not all. Some you can see the wire wound ballast resister.

 

[Dave999]

exactly it will be made from nichrome or similar wound round a glass fiber core and pressed onto the ceramic holder to help disipate the heat

for intersted parties there is loads of ballast here Everything You Need To Know About Ballast Resistor 2022

ballast is used here to mean "to balance" and it ballances the current flow to a level that is sensible for the circuit it protects.

it has nothing to do with the ceramic poweder often used to pack the ceramic holder of a balast resistor.

balance implies there could be some change that needs to be moderated or steared back to a steady state

Just like a load of lead shot in the hull of a boat keeps it upright, within bounds, it will always return to upright

you igntion will always try to moderate back to about 3 amps
hot ballast takes more volts across it and there are then fewer drving current through the coil
cold ballast takes less volts leaving more across the coil

and all this in the context that the resistance of the coil also varies
hot coil takes more volts to drive current through. less current means less through the ballast as well
ballast is therfore cooler
steals fewer volts
which means more volts across the coil
balanecs things back up

the balast and the coil primary share the avilble voltage in a ratio linked to the individual resistance of each.
that resistance varies with temperature in both cases
as one gets hotter and more restant the other cools and gets less so

all in all you end up with about 3 amps all the time regardless of which is hotter or cooler

hence the term ballast.

my explanation isn't quite right but it illustrates whats going on

i didn't go into the fact that in a series circuit the current is the same everywhere.. but better to get on the right footing than cram high school sicence down to the very last point

Dave

 

[Bewy]

Thanks for that. I suggested waaaaay back in post #14 that a 'balance' would better describe the resistor function in an ign cct but got shouted down with nonsense like ship's ballast....

 

[Dale Davies]

J

Thanks for that. I suggested waaaaay back in post #14 that a 'balance' would better describe the resistor function in an ign cct but got shouted down with nonsense like ship's ballast....

Always one smartass in the crowd, for the rest to ignore. Don't lose sleep over them.

 

[Dave999]

Thanks for that. I suggested waaaaay back in post #14 that a 'balance' would better describe the resistor function in an ign cct but got shouted down with nonsense like ship's ballast....

I know you did....
was in full agreemenbt with your statement

but disussions of agregates came back

i was in full agreement.

and yes i'm sure i come over as a smartarse from time to time but hey all i'm trying to do is help.

i also spell badly, don't use the correct punctuation and ramble on and on and on... always have,
if i was sitting with you all the words would have passed by in a flash.. and we would be agreeing on most points

 

[Bewy]

I do not think you are a s/arse at all. Always enjoy your posts, hope you do mine. [ From an ex-pat Pom ].