Polarize the system

[ILB]

I have a tractor with a 6 volt battery and a generator with a cut-out relay. Do I need to and if I need to, how do I polarize the system?

 

[Janicholson]

If it is not charging. it hurts nothing to give the gen a polarization. Use a foot or so of #10 solid copper wire (#12 will do) With the tractor shut off, and ignition off, jump from the Bat terminal on the cutout, to the arm terminal. This will spark a solid (not dangerous) yellow spark. Hold for one second. This puts magnetism into the field poles of the gen. Jim

 

[Janicholson]

This will take you farther Jim
John T system analysis

 

[john in la]

Momentarily touch Bat to Arm.

OR

Momentarily touch Bat to Fld.

What one is correct?
Your guess is as good as mine.
As you did not tell us what kind of tractor you have.
So we have no idea if you have a A or B circuit generator.

 

[JMOR]

(quoted from post at 19:59:52 04/14/15) Momentarily touch Bat to Arm.

OR

Momentarily touch Bat to Fld.

What one is correct?
Your guess is as good as mine.
As you did not tell us what kind of tractor you have.
So we have no idea if you have a A or B circuit generator.

ust make it simple. BATT to ARM will polarize the fields of either "A" or "B" circuit.

 

[john in la]

And here I thought I could remember reading in the Ford service manual that
Fords b-circuit system was bat to field

But thanks for setting me straight.

 

[Janicholson]

(((Not a Flame)) Though I failed to consider a "B" circuit tractor, There is no connection between the field and the Armature on a "B" circuit gen. The F terminal gets grounded inside the generator. The Field current is provided by hot side voltage from the regulator. A cutout only "B" generator would need to pickup voltage from a third brush, or an adjustable resistor from a hot source. Jim

 

[Janicholson]

You are correct in your memory. Jim

 

[John T]

Yall, we need to get back to engineering basics of what Polarization is and how its accomplished:

1) To Polarize you pass current through the field windings and creation of the electromagnetic field that is then generated imparts a degree of residual permanent type (NOT electromagnetic) magnetism into the soft iron field poles, ie you're magnetizing the iron when current flows through the field windings.

2) You polarize an A circuit (most tractors other then some Fords and some Masseys and a few others) by jumping off the VR or cutout relays BAT terminal over to the A terminal so hot battery voltage present on BAT causes current to flow through the field windings (on a 2 brush A genny the fields begin at the A post and end at the external F post) since the gennys external F terminal is grounded via the voltage regulator which gives F its ground path.

3) You polarize a B circuit (some Fords and Masseys and a few others) by applying hot battery voltage (such as present on a VR's BAT A terminal) to the external F terminal so current flows through the fields to ground as the other end of the fields is internally grounded. NOTE on a B circuit if you apply voltage to the A terminal, current flows through the armature to ground but NOT through the field windings IE NO POLARIZATION!!! The fields on a TWO BRUSH B start at the external F terminal then to the internal ground with no connection to A other then the armature as well as one end of the fields are both grounded.

DISCLAIMER I did this in a hurry I may be incorrect, but as I recall on a two brush genny on a B system the fields are between the external insulated F post and an internal ground with no connection to the armature circuit, the B armature circuit is between the hot ungrounded brush which wires to the external A post and the other brush which is grounded so applying voltage from BAT to A DOES NOT cause field current to flow (like it would on an A system) which is necessary to polarize the soft iron field poles. ISNT THAT CORRECT PROFESSOR JIM??????????????????????????????????????????????

Jim already posted my Troubleshooting Procedure but its ONLY for a Class A system NOT a B

I think the above is correct and Im stickin to until proven otherwise

SUMMARY Polarize an A system by jumping from BAT to A (current flows through fields then to ground via the VR)
Polarize a B system by jumping from BAT to F (current flows through fields which are between F and internal gnd)

What say other sparkies??????????????????????????????????????

 

[John T]

John, I think that's correct, on a B system you polarize by jumping BAT to F, see my post above

John T

 

[Janicholson]

Correct you are. Jim

 

[JMOR]

(quoted from post at 22:29:21 04/14/15) Yall, we need to get back to engineering basics of what Polarization is and how its accomplished:

1) To Polarize you pass current through the field windings and creation of the electromagnetic field that is then generated imparts a degree of residual permanent type (NOT electromagnetic) magnetism into the soft iron field poles, ie you're magnetizing the iron when current flows through the field windings.

2) You polarize an A circuit (most tractors other then some Fords and some Masseys and a few others) by jumping off the VR or cutout relays BAT terminal over to the A terminal so hot battery voltage present on BAT causes current to flow through the field windings (on a 2 brush A genny the fields begin at the A post and end at the external F post) since the gennys external F terminal is grounded via the voltage regulator which gives F its ground path.

3) You polarize a B circuit (some Fords and Masseys and a few others) by applying hot battery voltage (such as present on a VR's BAT A terminal) to the external F terminal so current flows through the fields to ground as the other end of the fields is internally grounded. NOTE on a B circuit if you apply voltage to the A terminal, current flows through the armature to ground but NOT through the field windings IE NO POLARIZATION!!! The fields on a TWO BRUSH B start at the external F terminal then to the internal ground with no connection to A other then the armature as well as one end of the fields are both grounded.

DISCLAIMER I did this in a hurry I may be incorrect, but as I recall on a two brush genny on a B system the fields are between the external insulated F post and an internal ground with no connection to the armature circuit, the B armature circuit is between the hot ungrounded brush which wires to the external A post and the other brush which is grounded so applying voltage from BAT to A DOES NOT cause field current to flow (like it would on an A system) which is necessary to polarize the soft iron field poles. ISNT THAT CORRECT PROFESSOR JIM??????????????????????????????????????????????

Jim already posted my Troubleshooting Procedure but its ONLY for a Class A system NOT a B

I think the above is correct and Im stickin to until proven otherwise

SUMMARY Polarize an A system by jumping from BAT to A (current flows through fields then to ground via the VR)
Polarize a B system by jumping from BAT to F (current flows through fields which are between F and internal gnd)

What say other sparkies??????????????????????????????????????

Yes, you are right about the , "I may be incorrect part".
{NOTE on a B circuit if you apply voltage to the A terminal, current flows through the armature to ground but NOT through the field windings IE NO POLARIZATION!!! The fields on a TWO BRUSH B start at the external F terminal then to the internal ground with no connection to A other then the armature as well as one end of the fields are both grounded.

DISCLAIMER I did this in a hurry I may be incorrect,....}

See the current path through the field coils in violet when Batt is applied to ARM in a "B" circuit system. As I said, both "A" & "B" can both be polarized by BATT to ARM.

 

[leej]

(quoted from post at 05:20:09 04/15/15)

(quoted from post at 22:29:21 04/14/15) Yall, we need to get back to engineering basics of what Polarization is and how its accomplished:

1) To Polarize you pass current through the field windings and creation of the electromagnetic field that is then generated imparts a degree of residual permanent type (NOT electromagnetic) magnetism into the soft iron field poles, ie you're magnetizing the iron when current flows through the field windings.

2) You polarize an A circuit (most tractors other then some Fords and some Masseys and a few others) by jumping off the VR or cutout relays BAT terminal over to the A terminal so hot battery voltage present on BAT causes current to flow through the field windings (on a 2 brush A genny the fields begin at the A post and end at the external F post) since the gennys external F terminal is grounded via the voltage regulator which gives F its ground path.

3) You polarize a B circuit (some Fords and Masseys and a few others) by applying hot battery voltage (such as present on a VR's BAT A terminal) to the external F terminal so current flows through the fields to ground as the other end of the fields is internally grounded. NOTE on a B circuit if you apply voltage to the A terminal, current flows through the armature to ground but NOT through the field windings IE NO POLARIZATION!!! The fields on a TWO BRUSH B start at the external F terminal then to the internal ground with no connection to A other then the armature as well as one end of the fields are both grounded.

DISCLAIMER I did this in a hurry I may be incorrect, but as I recall on a two brush genny on a B system the fields are between the external insulated F post and an internal ground with no connection to the armature circuit, the B armature circuit is between the hot ungrounded brush which wires to the external A post and the other brush which is grounded so applying voltage from BAT to A DOES NOT cause field current to flow (like it would on an A system) which is necessary to polarize the soft iron field poles. ISNT THAT CORRECT PROFESSOR JIM??????????????????????????????????????????????

Jim already posted my Troubleshooting Procedure but its ONLY for a Class A system NOT a B

I think the above is correct and Im stickin to until proven otherwise

SUMMARY Polarize an A system by jumping from BAT to A (current flows through fields then to ground via the VR)
Polarize a B system by jumping from BAT to F (current flows through fields which are between F and internal gnd)

What say other sparkies??????????????????????????????????????

Yes, you are right about the , "I may be incorrect part".
{NOTE on a B circuit if you apply voltage to the A terminal, current flows through the armature to ground but NOT through the field windings IE NO POLARIZATION!!! The fields on a TWO BRUSH B start at the external F terminal then to the internal ground with no connection to A other then the armature as well as one end of the fields are both grounded.

DISCLAIMER I did this in a hurry I may be incorrect,....}

See the current path through the field coils in violet when Batt is applied to ARM in a "B" circuit system. As I said, both "A" & "B" can both be polarized by BATT to ARM.

The same procedure for both is wonderful to know!!

Thank you for your long needed simplification! Why is the "A"/"B" polarization been made to look complicated for so long when it could have been so simple all these years? Thank you for presenting with such clarity.