# 2x battery packs, 2x controllers, series as sepex

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I know that a series has a different power distribution, wire gauge, and wire length than a sepex.

I want a battery pack voltage total of 120-144v

So I could make a total of 144v by splitting the total into a 60v pack, routed to a controller for the field, and a 84v pack to a controller routed to the armature. I would like to be able to connect the packs into the total pack.

Splitting the total based on the theoretical, mysterious, voltage sharing of a series motor.

Right? I hope...

If this works, I have another theory
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#### major

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I know that a series has a different power distribution, wire gauge, and wire length than a sepex.

I want a battery pack voltage total of 120-144v

So I could make a total of 144v by splitting the total into a 60v pack, routed to a controller for the field, and a 84v pack to a controller routed to the armature. I would like to be able to connect the packs into the total pack.

Splitting the total based on the theoretical, mysterious, voltage sharing of a series motor.

Right? I hope...

If this works, I have another theory
Sorry, you're way off base. There is nothing mysterious about a series wound motor. The important thing is the field current equal the armature current. The ratio of armature voltage to field voltage depends on load and speed but for a ball park use 100 to 3.

I have seen a case or two where for unusual reasons it has been done. It takes a thorough understanding of the series motor and design of two unique pwm controllers with a common control.

If for some reason you're set on the idea, study up on DC motor theory and control.

major

#### Iowa599

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The amperage is the same for field and armature. The voltage can be different for either, but total to supply voltage. I called that the split. That is the same as ratio.

I was concerned about PWM timing, I'm assuming the frequency is rather high. Why not run a large capacitor on the output?

#### major

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Doesn't wattage correlate to magnetism?
No.

There are some good tutorials on line as well as text books.

major

{edit} Sorry, got to go. Good luck.

#### Iowa599

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Ah ha!

Magnetic field strength is defined by amperage! Derp! Now I feel dumb

Then: