relay replacement

[jimzhog]

doing a rewiring on 50' Pan...while tracing wiring from picture came to relay circuit and saw NO RELAY ...what is this ???

HELP ...jimzhog

[RUBONE]

Looks like some kind of diode. Someone's better idea!

[flatheadDave]

It’s called a snap relay. And it’s a solid state relay that replaces the coil mounted type. A friend told me that they were popular in the 70s. I have a couple and have used them on a panhead before. You can still find them on Ebay. New ones that is.

[flatheadDave]

Here’s a pic.

[jimzhog]

Thanks for replying... first... before I started the rewire the bike was running fine etc.. looking thru PANHEAD SERVICE MANUAL...p 192 shows picture condenser connected to Gen.....previous page talks about Police Generator ..not sure what that means...parts catalog shows condenser as a "relay eliminator "..definitely requires more study ...

the reason for rewire was my trying to refit dash bracket and I started a smoldering mess of wires shorting out ...looks like mostly back end but ordered whole set to rewire if necessary...also there was NO Terminal Box...connections were made wire to wire then rolled up in tape...will get correct box ... This old man is having a ball learning and fixing Thanks again..jimzhog

[RUBONE]

Thanks for replying... first... before I started the rewire the bike was running fine etc.. looking thru PANHEAD SERVICE MANUAL...p 192 shows picture condenser connected to Gen.....previous page talks about Police Generator ..not sure what that means...parts catalog shows condenser as a "relay eliminator "..definitely requires more study ...

the reason for rewire was my trying to refit dash bracket and I started a smoldering mess of wires shorting out ...looks like mostly back end but ordered whole set to rewire if necessary...also there was NO Terminal Box...connections were made wire to wire then rolled up in tape...will get correct box ... This old man is having a ball learning and fixing Thanks again..jimzhog

Don't confuse a condenser (As used on an ignition or on a radio generator for noise suppression) with a relay replacing Diode. The Diode allows current through when the battery side falls below the rating it is set for, when the voltage gets back up it turns it off, like a relay but without the mechanical bits. They can be mounted inside a gutted relay as well, but tend to like cooling air.

[Mongrel505558]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

[RooDog]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

By "Lucas, Prince of Darkness"?

[Mongrel505558]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

By "Lucas, Prince of Darkness"?

The One and Only. About the only thing Lucas that worked. At least I never had a problem with one. It was actually an improvement over the selenium rectifier that it replaced that looked like it belonged in a crystal radio kit. The Lucas dual points plate is a whole other story. Lots of people, including myself, immediately replaced that with a Boyer Bransden or similar electronic ignition. The Boyer website euphemistically states "Some classic vehicles suffer from "fragile" electrics..."

[jimzhog]

Great information as usual from this forum... it's a big reason I am moving right along with my education on The Panhead...

Thanks again to all...jimzhog

[RUBONE]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

The zener is grounded, but the diode turns the excess juice into heat, hence the reason they were mounted in a big heat sink, the casting on later ones and the flat plate aluminum type on the earlier ones.

[Mongrel505558]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

The zener is grounded, but the diode turns the excess juice into heat, hence the reason they were mounted in a big heat sink, the casting on later ones and the flat plate aluminum type on the earlier ones.

I thought it was reverse biased and conducted when the voltage across it exceeded it's breakdown voltage, but I'm often wrong. In any case, I found out about the heat part when I accidentally touched the Zener on my Norton. Got a bad burn on my hand. Never had a problem with it, though.

Jim

[chop1543]

Norton Commando's and some other Brit bikes had a simple Zener diode in place of a voltage regulator. The concept is simple. It doesn't conduct until a certain voltage is reached, and then it conducts the difference in voltage to ground (the frame). Just one wire. Doesn't regulate current, though.

By "Lucas, Prince of Darkness"?

Lucas electrics....the reason the British drink warm beer.