Another electrical question (Sigh)

[55 50 Ron]

The write-ups by Clooney, John T, and other electrical experts (here on YT) say the voltage output from a generator "A" terminal should be "high" without the regulator connected, I.E., the generator is "open circuited" and can provide maybe 18 to 22 volts out for a nominal 12 volt unit, assuming it's a good generator.

However Rachel (fix it lady on Steiner You Tube videos) says 1.5 volts out of a 6 volt generator is correct. She doesn't identify the terminal she is referring to and isn't clear (to me anyway) the conditions of measurement. Maybe she is referring to the "F" terminal and 1.5 volts is correct for that terminal under certain conditions? I've never "played with" measuring voltage from the "F" terminal so am at a bit of loss in knowing what can be expected under either good or bad generator conditions.

Thanks for your helpful responses.

Hope you have a nice heated shop or garage to work in if you are in North cold country.

 

[Bob]

I think "Rachel" is just a pretty "talking head" for this site's competition, and wouldn't quote her as an "electrical expert".

Sure seems to reel in people to "over there", though!

If you copy the link below and paste it into your browser, and click on some of the electrical manuals (GSS-1310, GSS-1052C and several others) you can read some good IH electrical manuals, and since IH and DEERE both generally used Delco equipment it should apply to the green stuff, as well.

Let me know what you think of the info.

http://farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Blue%20Ribbon%20Service%20Manuals/index.html

 

[Bob]

(quoted from post at 14:21:37 02/15/20) The write-ups by Clooney, John T, and other electrical experts (here on YT) say the voltage output from a generator "A" terminal should be "high" without the regulator connected, I.E., the generator is "open circuited" and can provide maybe 18 to 22 volts out for a nominal 12 volt unit, assuming it's a good generator.

However Rachel (fix it lady on Steiner You Tube videos) says 1.5 volts out of a 6 volt generator is correct. She doesn't identify the terminal she is referring to and isn't clear (to me anyway) the conditions of measurement. Maybe she is referring to the "F" terminal and 1.5 volts is correct for that terminal under certain conditions? I've never "played with" measuring voltage from the "F" terminal so am at a bit of loss in knowing what can be expected under either good or bad generator conditions.

Thanks for your helpful responses.

Hope you have a nice heated shop or garage to work in if you are in North cold country.

Also:

https://www.google.com/url?sa=t&amp...5134.pdf&usg=AOvVaw3Z_xtqcS1UjnES9kF72mKE

https://www.google.com/url?sa=t&amp...-116.pdf&usg=AOvVaw36Lv-1bisQXEP_3RJpu5lO

 

[John T]

Hey Ron, you're an engineer but your question is making me think too hard lol

I don't recall but maybe I have said what the voltage on the A terminal should be ??? I've been on here over 30 years and no telling what all I said, I cant even remember yesterday even lol

HOWEVER I don't recall describing what it should be "WITHOUT THE REGULATOR CONNECTED" Seems like I've referred to the open unloaded output voltage (but I didn't mean no regulator connection, just no load on armature) saying it doesn't count as much as what the voltage would be when connected to a load (IE Battery). WITH THE FIELD CONNECTED TO A REGULATOR in which case it has "somewhat" of a ground or a resistive sort of ground (subject to what state the VR is in) I could imagine (I have no data to back up) it being say the 18 volts but when connected to a battery maybe 13 to 14+ volts subject to VR and RPM.

If I ever claimed it should read 18 volts WITHOUT REGULATOR CONNECTED ???? I don't recall nor do I necessarily now agree.

HERES WHAT I SAY TODAY:

If the VR isn't connected such that the Field is total open with zero field current the A terminal still exhibits voltage and that's subject to 1) RPM 2) The degree of residual magnetism present in the soft iron field poles (absent any field current) which weakens the longer the genny has sat unused.

I don't see how one can prescribe any exact number of voltage WITH REGULATOR DISCONNECTED when neither the residual field magnetic strength nor the RPM are known CAN ANYONE TELL ME HOW ????????????????????????????

Maybe that's the same Rachel from Card Services that calls me wanting to save me credit card interest.

Sorry, I dont know the voltage on the A terminal with no VR connected absent RPM and field strength and if I said it should be 18 volts I'm now officially RETRACTING THAT STATEMENT AND STAND CORREECTD hey I've been wrong before I think LOL

PS Im in the RV in Florida and its like 80 degrees woooooooooo hoooooooooo

NOTE Id love to hear what both you and Bob and anyone else has to say about your question cuz I DONT KNOW THE ANSWER

John T Obviously too longgggggggg retired electrical engineer and rustyyyyyyyyyyyyy

 

[55 50 Ron]

I didn't mean to imply that Rachel is an expert, sorry.

There are other (more) Delco Remy documents of service information besides those you referenced which are excellent write ups. I do have some of them but my main problem is not remembering that I have them. I need to "update" my bad memory and study what I've got.

Thanks again for refreshing memory for an old forgetful guy!

 

[55 50 Ron]

John,

You're right in line with my thinking on this. The "18 to 22 volts" actually was in a post from Clooney years ago when he used to post here and I don't recall if he stated his conditions associated with his comments.

GlenT was in on some of those comments too.

 

[TR3driver]

Even though imprecise (as you say), that's an important test because it's that initial output that gets the generator "started". IOW, with a regulator connected, that small voltage gets passed to the field windings, which increases the magnetic field and increases the voltage, etc, etc until the voltage comes up to around battery voltage and the cutout closes.

Exact value can vary, but at minimum charging rpm and with the generator polarized (magnetized as far as the iron will go), no connection to the F terminal, there should be at least a couple of volts on the A terminal.

Another thing to watch out for: There are several different ways of wiring generators internally, and I think Delco-Remy has made all of them at one time or another. For two-brush generators, the two major variations are:

I don't know about all Deere tractors, of course; but I do know that Ferguson used both types at the same time!

But I believe some Deere tractors had 3-brush generators, which introduces even more chances for variation.

 

[John T]

Your statement "Exact value can vary, but at minimum charging rpm and with the generator polarized (magnetized as far as the iron will go), no connection to the F terminal, there should be at least a couple of volts on the A terminal."

Makes sense and I tend to agree. While RPM and residual magnetic field strength would determine a more exact figure, a volt or two sounds more reasonable then 18 volts for darn sure. Of course, the open circuit unloaded voltage would be higher then when a load like a weak battery is applied.

John T Longgggggggggg retired n rusty electrical engineer

 

[John T]

Regardless a fun thread you started ??? Maybe my recollection was more accurate then I thought as I didn't remember ever quoting any 18 volts and when I said 'open unloaded voltage" I meant NO BATTERY ATTACHED TO THE A TERMINAL not no VR attached to the gennys FLD post.

I think this is a good informative thread for us sparkies at least

Take care Ron

John T

 

[Brownie450]

Many years back, we had a Delco 12-Volt generator repaired
at a service shop.
When it was finished, the guy put it on a test stand.
I wish I had paid more attention to how he had it connected,
because it was putting out 72 Volts according to the read-
out.
Only thing I could think was that he had the arm terminal
connected to the field terminal to get that high of Volts.

I really like the electrical discussions by the experts on
the forum.
I'm kind of big on the electrical thing myself.

Thanks for all of your shared knowledge, guys.
Jim

 

[TR3driver]

(quoted from post at 06:11:13 02/16/20) Many years back, we had a Delco 12-Volt generator repaired
at a service shop.
When it was finished, the guy put it on a test stand.
I wish I had paid more attention to how he had it connected,
because it was putting out 72 Volts according to the read-
out.
Only thing I could think was that he had the arm terminal
connected to the field terminal to get that high of Volts.

The problem with running them up to that kind of voltage is that the insulation on the wires on the armature is pretty thin. If there is a little nick or something, the higher voltage might punch through and create permanent damage. The old Delco literature I have says "just say no" (always use a load when testing output voltage); while Lucas says to limit voltage (by limiting rpm) to 20 volts.

High voltage is also hard on the field windings; can easily cause an inter-winding short or overheating.

Not really relevant, but a long time ago it was popular to rewire alternators to put out 110v DC. I've got plans somewhere for how to build an outlet box with a switch, that converts from normal battery charging duty to 110v DC; which can in turn be used to power many hand power tools (drill, Skil saw, etc). Many (not all) AC motors with brushes will actually run on DC just as well as AC.

 

[Blackhole49]

(quoted from post at 01:16:27 02/16/20) Hey Ron, you're an engineer but your question is making me think too hard lol

I don't recall but maybe I have said what the voltage on the A terminal should be ??? I've been on here over 30 years and no telling what all I said, I cant even remember yesterday even lol

HOWEVER I don't recall describing what it should be "WITHOUT THE REGULATOR CONNECTED" Seems like I've referred to the open unloaded output voltage (but I didn't mean no regulator connection, just no load on armature) saying it doesn't count as much as what the voltage would be when connected to a load (IE Battery). WITH THE FIELD CONNECTED TO A REGULATOR in which case it has "somewhat" of a ground or a resistive sort of ground (subject to what state the VR is in) I could imagine (I have no data to back up) it being say the 18 volts but when connected to a battery maybe 13 to 14+ volts subject to VR and RPM.

If I ever claimed it should read 18 volts WITHOUT REGULATOR CONNECTED ???? I don't recall nor do I necessarily now agree.

HERES WHAT I SAY TODAY:

If the VR isn't connected such that the Field is total open with zero field current the A terminal still exhibits voltage and that's subject to 1) RPM 2) The degree of residual magnetism present in the soft iron field poles (absent any field current) which weakens the longer the genny has sat unused.

I don't see how one can prescribe any exact number of voltage WITH REGULATOR DISCONNECTED when neither the residual field magnetic strength nor the RPM are known CAN ANYONE TELL ME HOW ????????????????????????????

Maybe that's the same Rachel from Card Services that calls me wanting to save me credit card interest.

Sorry, I dont know the voltage on the A terminal with no VR connected absent RPM and field strength and if I said it should be 18 volts I'm now officially RETRACTING THAT STATEMENT AND STAND CORREECTD hey I've been wrong before I think LOL

PS Im in the RV in Florida and its like 80 degrees woooooooooo hoooooooooo

NOTE Id love to hear what both you and Bob and anyone else has to say about your question cuz I DONT KNOW THE ANSWER

John T Obviously too longgggggggg retired electrical engineer and rustyyyyyyyyyyyyy

John, do you know where you will be at Flywheeelers?

 

[John T]

Row 74 site 18 far Northwest corner of show grounds (NOT far West in the Village) usually there in morning hours.

John T

 

[John T]

" I've got plans somewhere for how to build an outlet box with a switch, that converts from normal battery charging duty to 110v DC;"

I still have one of those 120 Volt alternator conversions at home somewhere with a 15 amp duplex receptacle. It was pretty simple actually

John T

 

[Brownie450]

RE: John T & the 110 Volt outlet.

It was used with a Delco alternator that had the external
regulator.
It amounted to a SPDT toggle switch which had the field
lead from the alternator cut & attached to the center
terminal of the switch.
The other half of the field lead going to the regulator
was attached to one of the outer terminals of the switch.

The output wire of the alternator [+12 Volts] was connected
to the remaining terminal on the switch & also to the hot
terminal on the 110 Volt outlet.

The outlet "ground" was connected to battery ground.

When the switch was in one direction, the alternator field
would be getting full 12 Volts & the wire going to the
regulator would be disconnected.
When the switch was reversed, the field would function
normally.

I used a red neon light for a Voltage indicator when engine
speed was correct.
Biggest drawback was that it only put out direct current.
Good for drills & resistive loads.
Pretty good for charging 24 Volt batteries, though.
Jim