24 volt system

[teddy52food]

Was the circuit to engage the starter solonoid 24 volt, or on the A or B circuit? If on 24, how was it wired?

 

[Machinery-Man]

On the previous post there is a diagram of the system placed for review.

 

[Anonymous-0]

The starter solenoid circuit comes from terminal A of the key switch. It is - polarity and goes from the key switch to the neutral safety switch to the small terminal on the solenoid. This is a 24 volt circuit and a 24 volt solenoid.

 

[ET]

The starter solenoid makes a conection of 24v to operate the starter. The solenoid is activated by 12v.

 

[John T]

Excellent question Teddy, go to the head of the class LOL. If you look at the 24 volt John Deere Service Manual SM 2029 wiring diagram as you follow this it will answer your question: (Im assuming Deeres Diagram is accurate and following it and assuming the universal GROUND symbol indicates a bond to the tractors metallic frame, thats how it was on all I owned and serviced at least, but I cant guaranteee its true on every tractor out there???)

1) The solenoid SWITCHES 24 VOLTS as the drawing shows it switches On/Closed or Off/Open one side of the 24 volts since it opens or closes (internally) where one one of the big battery cables attach. The other big battery cable connection goes direct to the other big starter post (as Deeres diagram shows) AND THATS 24 VOLTS.

2) HOWEVER the contacts activation circuit OPERATES AT ONLY 12 VOLTS.

3) From each outer untied battery post (+ of one - of other) a circuit wires up to the master switch, one is 12 volts POSITIVE GROUND (other is 12 volts NEGATIVE GROUND) with respect to the mid center battery tie point where the batteries attach to each other and frame GROUND AS SHOWN BY THE UNIVERALS GROUND SYMBOL ON THE JOHN DEERE DIAGRAM. When I owned, serviced and bought and sold those tractors that to frame grounding jumper was a small wire NOT any big battery cable mind you.

4) THEREFORE 12 volt Neg ground and 12 volt Pos ground (with respect to the mid center to frame tie point ground shown on Deeres Diagram) is available at the switch. Thats done so some loads are fed via the Pos grounded battery and others are fed off the Neg grounded battery to balance the battery loads

5) HOWEVER the solenoids activation pull in coil (creates an electromagnet) OPERATES AT ONLY 12 VOLTS. Remember theres only 12 volts from either outer untied battery post (+ of one - of other) with respect to the mid center tie point where the batterys join and theres that jumper to frame as shown on the diagram AND ALL TRACTORS I OWNED AND WORKED ON OVER MANY YEARS

Let me know if this helps Teddy, I know youre knee deep in electrical theory from your previous posts and Im deep in theory but my lifes training and experience has been in electrical engineering, farming, used tractor sales and service, and law NOT AS A TEACHER so im having a tough time explaining this to lay persons BUT HEY IM SURE TRYING MY BEST NOW

let me know if you have any more questions

Best wishes n God Bless all here who try to help and THANKS TO ALL OF THEM

John T Engineer but NOT a good teacher grrrrr lol

 

[Mike M]

Finally !!!!

John T is the winner !!!!

A very good and sensable reply using the proper terminology. And not trying on purpose to rename or redescribe everything adding to the confusion.

3 cheers for John T

 

[John T]

Thanks, but my main problem as a non trained "teacher" is that I get tooooooooooooo wordy and tooooooooo long winded and end up confusing the very same people Im trying so darn hard to help and its sooooooooo frustrating.

I know the electrical part but sometimes I just cant get it across grrrrrrrrrrrrr I have attended my friend Tom 43's excellent 24 volt Seminar and my friend Buick gave his first 24 volt seminar as part of one of my Workshop Seminars at New York expo ID SAY THEYRE BETTER TEACHERS THEN I AM

I still call a wiring connection to the metal frame of a tractor as a GROUND (and Deere uses the universal Ground symbol when they do that very thing) by golly n thats my story n Ima stickin to it regardless

I do try, thanks again for your kindness

John T

 

[Tx Jim]

John T
THANK YOU for your explanation.
OK John the 4020 wiring schematic I posted does not contain the UNIVERALS GROUND SYMBOL for the headlights similar to the 2 cyl wiring schematic. I know on both series of tractors the headlights operate basically the same. Do you think the ground symbol was inadvertently left off the 4020 wiring schematic by accident by the preparer?Thanks,Jim

 

[LarrySTN]

If you disconnect the "ground or neutral" wire from the battery to the frame, the starter solenoid will still work. If it will still work it is 24 volt. The solenoids are sold as 24 volt not because is switches 24 volt but because the activation circuit is 24 volt. The solenoid really doesn"t care how much voltage is switched only what the activation voltage is.

 

[55 50 Ron]

Tom,
What do you mean by "the neutral safety switch"?
Ron

 

[John T PS]

Okay I just ate a late lunch after I took a 10 mile bicycle ride grrrrrrrrrr wife made me lol and I realized from the diagram THERES NO REASON THE SOLENOIDS ACTIVATION COIL CANT BE 24 ORRRRRRRRR 12 VOLTS ACTUALLY....As I see it EITHER can work........

Theres only one wire down from the switch so its an A or B feed (either only 12 volts to frame ground) HOWEVER theres BOTH A and B circuits down on the starter or solenoid SOOOOOOOOOOO if say A came down (or B) the solenoids coil can still work at 24 volts because A and B are down there readily available and remember its 24 volts from A to B HMMMMMMMMMMMMM

Im also concerend that unlike at the fuel gage and lights which use ground (Deeres Ground symbol + allllllll the tractors I worked on) THEY DONT HAVE A GROUND SYMBOL THERE HMMMMMMMMM The 24 volt tractors I owned, sold and worked on (manyyyyyy) had an actual to frame connection GROUND where shown on the SM 2029 Wiring Diagram like at the gauges and lights and batteries but the solenoid wouldnt need one being mechanically fastended to all that heavy iron frame SO AGAIN I CAN SEE HOW 12 OR 24 COULD WORK

Although its still possible they are using the frame ground as a 12 volt return they arent sahowing the ground symbol there

SO ALL I CAN SAY FOR SURE IS IT CAN BE 12 OR 24

My friend ET who I met at one of my Electrical Seminars at the New York Expo worked at Deere in those years I think, IS THE SOLENOID COIL 12 OR 24 ET????????????

Maybe Mike M was too fast in his congratulations and kind words lol

Hey I been wrong before or so says the first wife lol

ET what say you???????????

John T

 

[Anonymous-0]

With all due respect, John's response, while long is totally incorrect with regard to the 24 volt cranking circuit. Since my seminar at Gathering of the Green is only a month away, I am compelled to not let error pass for truth. Some poor soul may be led astray.

1) The 24 volt starter, whether Two-Cylinder or New Generation is TOTALLY isolated from the frame of the tractor. This includes the 24 VOLT SOLENOID which encapsulates both the pull in and hold in windings. I repeat THE CONTROL CIRCUIT, WHICH INCLUDES THE SWITCH AND THE PUSH BUTTON AND SOLENOID is isolated and is 24 VOLT.

2) The starter, generator, voltage regulator, and SOLENOID are all 24 VOLT and isolated from the frame(if they aren't you have big problems).
These components would work just as well if the tractor frame were made out of wood or rubber.

3) This post is not just a difference of opinion or about semantics. Everyone is entitled to their own opinion but not their own FACTS. We are talking about a fundamental understanding and appreciation of the system not just the fleeting pleasure of winning an argument!

4) This factual information can be checked in a Deere parts book or service manual.

 

[Anonymous-0]

Ron,
There is no neutral safety switch on the Two-Cylinder tractor. The New Generation has a safety switch on the transmission that interrupts the control circuit unless the tractor is in park or neutral. My neighbor was killed because he bypassed it and the tractor ran over him.

 

[John T]

First off youre welcome, I just cant say why or why not Mother Deere used or didnt use the Universal Ground symbol on New Generation Diagrams. I hav posted the old gen 24 volt system manyyyyyyy times but seen no official Deere New Gen

I CAN SAY Where its used on their SM 2029 Diagrams there was indeed (on the many I owned and serviced) an actual to frame (I call Ground) connection like where the batteries join in the center and lights and gauges JUST LIKE THE DIAGRAM SHOWS

HOWEVER just because they used say two wires to a light that may just mean they did that instead of relying on the actual right there to frame electrical connection SINCE RUST AND CORROSIION AND LOOSE CONNECTIONS CAUSES SOOOOO MANY LIGHTS TO NOT WORK.

BUT THAT DONT MEAN that second wire dont lead back to frame ground or the mid battery tie point etc at a better place less conducive to rust and vibration electrical contact failures I.E, ID STILL REFER TO THAT SECOND WIRE AS A GROUND WIRE even if it dont connect to the fender/frame/GROUND right at the light location.

ALSO if the 12 volt lights didnt rely on a frame GROUND (call it battery mid tie poit if you like, but thats DEFINITELY direct tied to the frame) and one burned out and opened the series 24 volt circuit NO LIGHTS WOULD WORK.

HOWEVER I believe on those tractors one side can burn out yet the other can still work???????? And if thats so,,,,,,,,,its because the other non hot light terminal has to get back to the mid battery tie point somehere (where the 2 join and bond to frame) and just because they use a wire versus the sheet metal of the fender DONT MEAN THE LIGHTS ARETN STILL 12 VOLT AND CONSIDERED AS GROUNDED SOMEWHERE even if a wire is used versus direct tie to fender

Thanks sooooooo much for your kind words I appreciate it

Sorry I cant answer your question exactly but Ido know the ligts are 12 volt and its ONLY 12 volts between an A or B feed (at switch) and the mid battery tie point and thats bonded to theframe so I STILL CALL THAT GROUND. Again however remember,,,,,,,if BOTH lights are on and working and theres a connection from one to other either frame or a wire they can STILL WORK IN SERIES AT 24 VOLTS SINCE TWO 12'SARE TOGETHER EVEN IF THAT MID TIE POIUNT FRAME GROUND CONNECTION IS OPEN OR BROEK OR MISSING (as can happen) That way they can still work UNGROUNDED
but thats NOT the norm since if one burns out the other wont work UNLIKE the scenario if they each hae theor own to frame ground either direct to fender or a wire across to a better ground location

WHEWWWWWWWWWWWW LOL

Hope this helps let me know?????????

John T Thanks agian for your kindness

 

[Mike M]

Nope. I still think what you wrote matched what I am seeing in the schematics and remembering.

I think TOM43 has alot of work to do before a presentation is to be made.
Someone needs to have a tractor at the GOG and a voltmeter and do a hands on check.
I don't have batteries in mine or I'd confirm what the schematics show. I really don't doubt them. Others seem to want to rewrite them however ?

I mean no disrepect,but much of what has been written here about this is TOTALLY WRONG INFO !

 

[ET]

As sombody already said bat. A on the switch powers the solenoid. Bat. A is 12v.

 

[John T]

Thanks again, what I wrote is mostly correct but since Christ walked the earth NO ONE is perfect certainly not me..However I cant say for sure from the diagram that the solenoid cant work at 24 volts nor can I say it cant work at 12. As I noted I was concerend it may NOT be 12 since that would require a frame ground HOWEVER that diagram does NOT show a ground there unlike at the lights and fuel gauge and batteries. It can still work at 12 but would have to use the frame chassis however if it works at 24 no such connection is required

An old friend ET worked at Deere then which is why I asked him.

Had Deere shown the ground there Id be more confident it was 12 but since they dont that leans more towards 24. REGARDLESS it can work at EITHER its only if at 12 it does require use of the frame as a current return path like the lights and gauges and thats certainly possible. Were ONLY talkin a single coil of wire which can easil;y work at 12 or 24 but with no ground shown like at lights and gauges Im afraid Im leanin more now towards 24 WHICH IS WHY I QUICKLY POSTED MY PS CORRECTION

Thanks again maybe ET can enlighten us all

God Bless yall here

John T

 

[John T]

Thanks ET when we met I remember you worked at Deere then I believe which is why I asked. As I posted in my PS Correction its possible to work at 12 or 24 (but needs a ground if 12 and none is shown like at lights and gauges makes me a bit suspicious of 12????) subject to 12 requiring a current return path via the iron frame buy hey the lights and gauges and the battery to frame ground connection are there ya know for those 12 volt loads....

Maybe we will meet again in New York, thanks old friend

John T

 

[Mike M]

John & ET ; Both of you and I seem to be on the same page. The correct one at that !

 

[ET]

Is there an internal ground in the solenoid?

 

[Kurt_JDB]

I would think that the starter solenoid is like any other starter motor solenoid I have seen, with one hot lead to the switch and the circuit is completed through the case of the starter/motor/frame/battery. It"s grounded to the A battery ground. I"m not familiar with these tractors, but I have to think the case of the starter motor is grounded to the frame, although internanly yhe working parts of the motor are not, as they clearly are not connected to the frame.


Kurt

 

[Cliff Nelson]

Solenoid circuit is definitely 24 volt. Simple test turn the switch on and probe the terminals on the push button with a volt meter. pushing the button completes the 24 volt circuit.

 

[teddy52food]

Thanks, John. By studying The diagram, I would think it is 24 volt circuit. I wish they had the internal windings of the solinoid pictured, then we could know for sure. If I remember from working on a 3020D, it would start with the mid point battery wire burned off. I never did find out why that wire burned off, so I wired in a circuit breaker. That was many years ago (25 or 30) & I think he still has the tractor & his son is using it now.

 

[John T]

ET worked at Deere and he's a good man on new generation as I recall. Were pretty well on the same page as you noted but not quite exact as I still quetion no ground symbol on the solenoid (needs a ground for 12 volt) and if it doesnt use frame ground then its 24 volt but AGAIN either can be made to work...

Take care now

John T

 

[John T]

Youre welcome Teddy take care now thanks for the feedback. Yep the diagram dont show the details inside the solenoid unfortunately but its basically just a coil of wire with one end to the wiring terminal and other end to frame if its 12 volt but to the opposite polarity (A or B) post if its 24

John T

 

[Tx Jim]

This isn't a wiring diagram but it might help.

 

[John T]

Thanks for posting that Jim it may help but its not quite as good as a dern wiring schematic grrrrrrrrrr lol

HOWEVER HERES A SURE FIRE WAY TO TELL IN 1 MINUTE WITH A SIMPLE OHM METER

Some including a JD mechanic say its 12 volts

Others say its 24

Neither posted an internal solenoid schematic

I originally posted 12 BUTTTTTTT only a few minutes later re posted a correction it may be 24 since the JD SM 2029 wiring diagram DOESNT SHOW A GROUND THERE !!!!!!!!!!! and that supports its 24 volts instead

1) Its only a simple coil of wire with one end out to the small terminal that wires up to the start switch.

2) The other end of the coil has to lead somewhere and have a connection so current can flow well DUHHHHHH

3) If the other end IS NOT tied to the case/frame but instead connects to the opposite polarity batterys hot lead somewhere ,THEN ITS 24 VOLTS

4) If the other end connects to the case/frame then its 12 volts

SOOOOOOOO unhook everything or if you just have a solenoid handy use it.........Connect one ohm meter lead to case/frame,,,,,,,,,,connect the other lead to the small input activation terminal on the solenoid that wires up to the start switch

IF THERES CONTINUITY THEN IT WORKS AT 12 VOLTS

HOWEVER if there IS NO CONTINUITY BUT there is continuity to the other big hot post lead (thats to the opposite grounded polarity battery)

THEN ITS 24 VOLTS PIECE OF CAKE

See yall if you understand the basics of how this all works you can figure it out yourself AND DONT NEED TO GUESS OR RELY ON CONFLICTING OPINIONS POSTED HERE

woooooooooooooo hooooooooooooooooo

John T

 

[teddy52food]

#3 & 6 shows the wire comeing out of the cap & not connected to the case, so it would be 24 volts.

 

[M-MAN]

It would be called 24 even though you are only using 12 to energize the solenoid. 12 sitting there already & 12 more from the push button complete's the circuit. If my crs isn't acting up the orig question was (to engage the solenoid)? That would be 12.

Ain't no wonder we all want to get rid of the 24v system's. LOL

 

[John T]

Heck then it looks like either answer 12 or 24 can be made to be correct lol

John T

 

[Tx Jim]

I agree with M-Man. I vote for 24V although you can check the wire going to the "S" terminal and it should show 12V's but the solenoid engagement windings are actually 24V's.

 

[teddy52food]

But 12 + 12 = 24, just like the starter itself.

 

[M w J]

I have not worked on the start system of a 4010 for 30years. But what I remember is the solenoid is 12 volt . There is a relay that sends the other 12 volts to the other post on the field coil. The only thing 24 volt is the starter and generator Its like having 2 12 volt systems in 1 one negative ground and 1 positive They were called 24volt but that was not an accurate term.

 

[Tx Jim]

M w J
I agree as I stated earlier if the little ground wire that some prefer to call a "chassis connection" is intact then one can test the yellow solenoid exciting wire at solenoid and should get 12 V's with key in start position BUT HERE'S THE KICKER. There no 12 volt ground(chassis connection) in the starter to complete the 12V circuit so it has to connect to the other 12V battery to complete the 24V CIRCUIT to activate the solenoid. Look at the exploded photo of the solenoid I posted earlier and trace where the 2 ends of the solenoid coil wires attach to wiring harness and it won't be a chassis connection(ground).