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Generator Output at Idle

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H

HealeyKissed

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65 BJ8

How much power does the generator put out at idle? BCS answered with "barely enough power to cover at idle". Does anyone know of the number/units of power to answer the question? I've research many books/manuals and can't find the answer.

Rob
 
Rob- if it's a generator (and not an alternator), the voltage output depends on the make/model of the generator. The key word is *low* - hardly any voltage at normal warm idle rpm, ca. 750 rpm. Around 6v wouldn't be abnormal.

Keep in mind - a generator doesn't produce "power". It produces voltage, which increases as the engine/generator rpm increases..
 
NutmegCT said:
Rob- if it's a generator (and not an alternator), the voltage output depends on the make/model of the generator. The key word is *low* - hardly any voltage at normal warm idle rpm, ca. 750 rpm. Around 6v wouldn't be abnormal.

Keep in mind - a generator doesn't produce "power". It produces voltage, which increases as the engine/generator rpm increases..
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Thank you. No problems with the Healey. This just something that I wanted an answer for & couldn't find.

Rob
 
Somewhere I read that at idle 800rpm ish the ignition warning light should be just barely glowing/blinking .
 
NutmegCT said:
Rob- if it's a generator (and not an alternator), the voltage output depends on the make/model of the generator. The key word is *low* - hardly any voltage at normal warm idle rpm, ca. 750 rpm. Around 6v wouldn't be abnormal.

Keep in mind - a generator doesn't produce "power". It produces voltage, which increases as the engine/generator rpm increases..
Click to expand...
Generators are not variable voltage…
 
Bob_Spidell said:
Fortunately, Healeys have voltage regulators.
Click to expand...
And fortunately Healeys do not have ammeters to worry you by showing that your system is discharging at low rpm's.
 
Doesn't the ignition light in the tach indicate current flow (lit=from battery; unlit=to battery)? I have a Smiths ammeter I never installed because running a couple wires carrying potentially full battery current through the scuttle made me nervous.
 
Bob_Spidell said:
Doesn't the ignition light in the tach indicate current flow (lit=from battery; unlit=to battery)? I have a Smiths ammeter I never installed because running a couple wires carrying potentially full battery current through the scuttle made me nervous.
Click to expand...
Hi Bob--

You're correct as the light does serve to tell whether current is flowing in or out of the battery.

Years ago when I lived in Florida I had an early E-Jag which had, I think a 30 amp generator and an ammeter. The car was equipped with AC and with it and the lights on and/or wipers running the needle was always hovering at or around 0.

You can use a shunt to avoid the risk of a short.
 
Wouldn't a shunt require a different gauge; essentially a voltmeter with an inductive pickup? But, yeah, that would be the way to go.
 
Bob_Spidell said:
Wouldn't a shunt require a different gauge; essentially a voltmeter with an inductive pickup? But, yeah, that would be the way to go.
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Bob--

You certainly know more about electrical theory than do I but yes, an ammeter working off of a shunt must be different than one with direct wiring as the gauge is displaying the current flow by measuring what is happening in the shunt, right?

A friend of mine has a beautiful 246 Dino which has---or had--an ammeter with direct wiring. Somehow or other a short occurred behind the dashboard, resulting in a fire. His insurance company--I think Grundy--paid for a completely new interior, wiring harness, etc. to the tune of about $80K.
 
Michael Oritt said:
Bob--

You certainly know more about electrical theory than do I but yes, an ammeter working off of a shunt must be different than one with direct wiring as the gauge is displaying the current flow by measuring what is happening in the shunt, right?

A friend of mine has a beautiful 246 Dino which has---or had--an ammeter with direct wiring. Somehow or other a short occurred behind the dashboard, resulting in a fire. His insurance company--I think Grundy--paid for a completely new interior, wiring harness, etc. to the tune of about $80K.
Click to expand...
Ammeters are really just voltmeters that measure the voltage across a calibrated shunt. The higher the current flow, the higher the voltage across the shunt. Usually, the shunt is inside the meter, but can be outside.
 
One of the best monitors of the electrical system is a voltmeter, and no heavy current is wired into the dash with it. I put it on the parcel shelf of my 100/4, and glance over to it now and then to see if things are working as they should.
 
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