Field wire turn off

[bearman]

Want to turn off alt when making a pass at the track. Installing a toggle switch on the field wire will just turn off the alt correct or some other idea.

 

[dvw]

Just disconnect it. Make a run back to back. I'll bet it doesn't change anything.
Doug

 

[Nacho-RT74]

I would install the switch before the regulator. I don't think the switch after the regulator will be a good idea. The regulator would keep working trying to compensate the voltage decay still if alt is not being feeded and some damage could float on as soon you activate the switch with engine running.

There is a reason why alts from factory got a red label on field warning you to not disconect the wire while engine/alt is running.

 

[RJRENTON]

I would install the switch before the regulator. I don't think the switch after the regulator will be a good idea. WHY? The regulator would keep working trying to compensate the voltage decay still if alt is not being feeded and some damage (INCORRECT ASSUMPTION .. NO VOLTAGE OR CURRENT WILL BE FLOWING = NO HARM) could float on as soon you activate the switch with engine running. WHT IS THE REASON ?..... EITHER B4 OR AFTER THE REGULATOR? THE ALTERNATOR WILL NOT CHARGE IF IT HAS NO FIELD VOLTAGE APPLIED.....PERIOD

There is a reason why alts from factory got a red label on field warning you to not disconect the wire while engine/alt is running. WHICH YEAR, WHAT CAR, WHAT ALTERNATOR, WHERE IS HIS TAG LOCATED

Incorrect information once again. The purpose of disconnecting the alternator field wire is to keep the alternator from consuming horsepower while running the 1/4 mile....to use the horsepower to propel the car, rather than making amps and volts. I concur with DVW.....the change will be minimal if any. The world will not come to an end if the run on the battery for 30 seconds or so.......
BOB RENTON

 

[Badvert65]

I have been toying with the idea of using one of the vacuum actuated switches used to cut out air conditioning when accelerating. I was going to wire it into the charging circuit to cut that out when making a pass.

 

[Nacho-RT74]

Hell I KNOW WHY HE WANTS TO DISCONECT THE FIELD WHILE IS RACING!

Mabe not working with load, but activated and will get a voltage peak if activating field with engine running at RPMs

tag!

tags reproductions

1966-74 A B E-Body Alternator Warning Tag

DD0435 1965-1970 Chrysler models Alternator Warning Tag.

 

[Nacho-RT74]

I have been toying with the idea of using one of the vacuum actuated switches used to cut out air conditioning when accelerating. I was going to wire it into the charging circuit to cut that out when making a pass.

There are RPMs switches, that you can set anyway you want setting an RPM activator, or cut off switch... even being an RPM window to activate o deactivate whatever you want.

You could use also a microswitch linked to the carb throttle lever to cut off power when giving full throttle no matter the RPMs

 

[Nacho-RT74]

There are RPMs switches, that you can set anyway you want setting an RPM activator, or cut off switch... even being an RPM window to activate o deactivate whatever you want.

You could use also a microswitch linked to the carb throttle lever to cut off power when giving full throttle no matter the RPMs

This is one similar to one I bought LONG time ago ( maybe 12 years ago ). The one I got was able to be programed as turn on or cut off switch aside also a window switch. I was planning to use it for the compressor clutch too, allong with also a micro switch for the full trottle sensing where the RPMs are not really a straight relationship... I.E: passing a car on higways or roads

Intellitronix N3012 RPM Activated Switch Adjustable 2,000 to 9,800 rpm | eBay

 

[RJRENTON]

Hell I KNOW WHY HE WANTS TO DISCONECT THE FIELD WHILE IS RACING! IF YOU KNOW, WHY NOT STATE THE REASON.

Mabe not working with load, but activated and will get a voltage peak if activating field with engine running at RPMs

tag! SINCE THE ALTERNATOR IS NOT PRODUCING ANY VOLTAGE OR CURRENT, THERE WILL BE NO VOLTAGE PEAK AT TURN ON NO MORE SO THAN AFTER JUST STARTING THE ENGINE.


View attachment 1298149



tags reproductions

1966-74 A B E-Body Alternator Warning Tag

DD0435 1965-1970 Chrysler models Alternator Warning Tag.

See comments in red above. Once again incorrect assumption.....
BOB RENTON

 

[Nacho-RT74]

Blahblahblah... why would I need to state the reason?, that's OP job not mine.

Just thinking out loud but factory gave us a clue to disconect alt before reg instead before the field... on late 70s a relay was installed to keep out of the game the reg while cranking. "Dunno why" but sure they know better than me.

Anyway, there is no reason to keep "activated" the regulator doing nothing and is closer to the cab than the field... cut the power to reg and done.

Of dual field/elect reg, one of fields will be cut anyway installing the switch before the reg but with inactive reg at the same time. If single field/mech won't even need to cut a wire, just disconect and reuse the existant terminal to attach a female plug to run it to the toggle switch

 

[kiwigtx]

.

 

[bearman]

Blahblahblah... why would I need to state the reason?, that's OP job not mine.

Just thinking out loud but factory gave us a clue to disconect alt before reg instead before the field... on late 70s a relay was installed to keep out of the game the reg while cranking. "Dunno why" but sure they know better than me.

Anyway, there is no reason to keep "activated" the regulator doing nothing and is closer to the cab than the field... cut the power to reg and done.

Of dual field/elect reg, one of fields will be cut anyway installing the switch before the reg but with inactive reg at the same time. If single field/mech won't even need to cut a wire, just disconect and reuse the existant terminal to attach a female plug to run it to the toggle switch

Thank you for the inputs

 

[RJRENTON]

Blahblahblah... why would I need to state the reason?, that's OP job not mine. IMO...THE BEST THING FOR YOU TO DO IS: (like when approaching an unguarded rail road crossing) STOP-LOOK and LISTEN or know your subject before proceeding.

Just thinking out loud but factory gave us a clue to disconect alt before reg instead before the field... on late 70s a relay was installed to keep out of the game the reg while cranking. "Dunno why" but sure they know better than me.....ABSOLUTELY "they know better than me" ..... most everyone does know better.

Anyway, there is no reason to keep "activated" the regulator doing nothing and is closer to the cab than the field... cut the power to reg and done. WHY? Explain your reasoning.

Of dual field/elect reg, one of fields will be cut anyway installing the switch before the reg but with inactive reg at the same time. If single field/mech won't even need to cut a wire, just disconect and reuse the existant terminal to attach a female plug to run it to the toggle switch. WHY? HOW WILL ONE OF THE "FIELDS" be cut? The circuit path to ground is thru a transistor that conttols the current thru the field.....there is nothing to "cut"....the transistor will be biased OFF (no current flow).

By commenting, you are offering an opinion, which in this instance is totally incorrect.
BOB RENTON

 

[bearman]

Mr.mod please pull or delete this post thank you.

 

[RJRENTON]

Mr.mod please pull or delete this post thank you.

Bearman,
Pkease PM me re your comment....
BOB RENTON

 

[RemCharger]

Don't delete!
We still need to know why you need more hp at the track!

 

[bearman]

As for hp every little bit helps. As my 64 dodge has been on a diet for a couple years. I was reading some old hot rod mags and one of the articles was about shutting down the alt so I thought I would just ask about the idea.

 

[451Mopar]

Most of the power lost to the alternator is from the alternators cooling fan, not the electrical load.
About 1 HP of electrical load from the alternator, the alternator output would have to be around 50 Amps.

 

[Nacho-RT74]

I will repeat, because it seems is not being reading at all ( tipically ):

1-I didn't say to save LOAD but just kept ACTIVATED. There is no reason why keep ACTIVATED ( handling load or not ) the regulator to feed NOTHING... so WHY NOT cut the power BEFORE the reg? Is like a relay to source headlights. With no headlights sourced from 87 terminal, if being triggered and grounded via 85/86 terminals, the relay is activated, without load throught 30-87 terminals but still activated ( and anyway, that it takes some MINIMAL load to the full car circuitry but being a mechanical action ona mechanical system, sure not the same with a transistors setup )

2- as an experience taken from Mopar engineering from later 70s Mopars ( after some learning thought the years ) got regulators cut while cranking via an added relay which sensed the moment the engine was being cranked.

And will add one more:

3- If alternator was internally regulated ( or we were working on a Chebbby ) the power to cut the alternator job will be made just cutting the ONLY source posible which is the source for the REGULATOR.

So, aside your obsessive tendency to be againts my posts, theories, ideas, opinions or whatever... I remark or maybe ask:

WHY THE HELL IS A WRONG IDEA TO CUT THE REGULATOR SOURCE TO ACHIVE THE INTENDED GOAL BY THE OP?

And that's all. Nothing more to add from now on here ( I THINK )

 

[Nacho-RT74]

Most of the power lost to the alternator is from the alternators cooling fan, not the electrical load.
About 1 HP of electrical load from the alternator, the alternator output would have to be around 50 Amps.

Well I have been able to feel some dragging when alt is providing power on a "high" load stage. 1HP per 50 amps? Hell I don't know. I think could be a bit more, but can't say it certainly.

Net vs Gross power makes a big difference, sure not because just the alt, but adding water pump and... steering pump too? Dunno if we talk about cars without power steering.