1956 voltage regulator question

[swatson999]

I need a little help here. I have a 56 w/ a 12V generator system. In what was perhaps a misguided attempt to add a Bluetooth-enable speaker, several weeks ago we bought one and connected it with keep-alive power on the batter (actually, on the battery post on the ignition switch), and the full power line on the accessories post. That may have set off this cascade.

I noticed shortly afterward that the generator light was staying on longer than it was previously, but it would go out after hitting normal around-town speeds/RPMs. Until this morning, when it didn't go off at all. I had also started to notice some static on the BT speakers, but attributed it to ignition noise. Maybe not.

So thinking my VR had gone bad, I bought a replacement one, and installed that. Started up, and voila! Generator light went off as normal. Until the *next* start later in the day, when it didn't go off at all. Sigh. Drove to my car buddy's house and the troubleshooting began.

What we found was that the cut-out relay was not being pulled down, but if you pushed it down, it would stay down. Forever. Even after the car was shut off. So clearly *that's* wrong. We swapped back in the old VR. Similar behavior. Finally realizing (duh) that the last change was the BT speaker, we removed that from the equation by disconnecting it, but the problem remained. And when the VRs stayed closed after shutdown, they got hot, and i mean HOT, like too hot to handle hot.

So we have an hypothesis, and some questions.

Hypothesis: the keep-alive circuit somehow was causing the cut-off relay to remain energized, and after shutoff, it just crapped out the inner, fine-wire windings, and the only thing pulling the relay closed initially was the small-gauge (thick) wire outer windings from the generator. Does this make sense?

And two more questions: the shop manual states that on engine start, the generator creates a voltage that flows to the VR, closing the cut-off relay and thus connecting the battery to the VR. But HOW DOES IT DO THAT? I thought a generator could only create a current if the Field were energized, and it's not energized when the cut-off is open at start! What the...?

Second question is similar...once the battery is connected to the VR circuit via the cut-off relay, when the car is shut off, how on earth does the relay *open*? The battery is directly connected to the circuit, there's no switch anywhere to remove battery power from the relay! Is the current somehow inducted into the large windings, which then go to ground and the field collapses or something like that?

It's been a hell of a frustrating afternoon, and further work will have to wait for the replacement VR to arrive Monday morning, but in the meantime...can anyone help us sort this out? Any and all help is MUCH appreciated!

TIA! Steve

 

[biddle]

Using abbreviations like "VR" which most people would associate with virtual reality is not recommended. This also effects site searches and google searches. Not sure why you did this since your post is so long. Your subject "VR problems and questions" has been revised.

 

[jack-in-sac]

The addition of the speaker is obviously the problem. Try removing it and make sure everything in the charging system is still in working order. It appears that the blue tooth keep -alive is fooling the battery charging system. What did the instructions say about installation? This may be causing feedback to the voltage regulator. I assume you polarized the voltage regulator upon installation. If the bt speaker is for installation a later model car with an alternator. That could be an issue. I am just throwing ideas out, nothing written in stone. Out of curiosity, why do you need a keep-alive speaker as opposed to a conventional speaker? A possible solution is a diode inline to stop feedback to the charging system. In your paragraph 2 I believe the battery is used to spin the engine over to start the engine and thus the generator is then turning to recharge the battery. when the engine runs the starter is then to be disengaged.

 

[jimntempe]

I've read what you did several times now and don't see how it would have caused your problem. I think it might just be coincidence or perhaps you moved a wire under the dash and that's caused the problem.

 

[swatson999]

The addition of the speaker is obviously the problem. Try removing it and make sure everything in the charging system is still in working order. It appears that the blue tooth keep -alive is fooling the battery charging system. What did the instructions say about installation? This may be causing feedback to the voltage regulator. I assume you polarized the voltage regulator upon installation. If the bt speaker is for installation a later model car with an alternator. That could be an issue. I am just throwing ideas out, nothing written in stone. Out of curiosity, why do you need a keep-alive speaker as opposed to a conventional speaker? A possible solution is a diode inline to stop feedback to the charging system. In your paragraph 2 I believe the battery is used to spin the engine over to start the engine and thus the generator is then turning to recharge the battery. when the engine runs the starter is then to be disengaged.

I agree...the speaker was the most likely culprit, and we've disconnected it from the system. If reinstalling, it will have all power coming from the ACC terminal, so only hot when the car is on. I *think* it needed the keep-alive power to hold up memory with any settings, which is dumb in today's world of NVRAM flash memory, but who knows?

We did *not* polarize the generator when installing the new VR, but will certainly do so when putting in the new new one tomorrow!

I think I understand the residual magnetism and how that kicks things off in the VR now....we'll just have to see if everything comes together tomorrow...new VR, polarize the generator, reconnect F wire to VR, fully charged battery, no BT radio...wish me luck!