# Series motor with 4Q controller

**URL:** <https://community.electricforum.com/t/series-motor-with-4q-controller/6400>\
**Category:** Battery & Chargers\
**Created:** [October 6, 2016, 9:59pm UTC](https://community.electricforum.com/t/series-motor-with-4q-controller/6400 "2016-10-06T21:59:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![nevbuggie](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@nevbuggie](https://community.electricforum.com/u/nevbuggie)\
**Post date:** [October 6, 2016, 9:59pm UTC](https://community.electricforum.com/t/series-motor-with-4q-controller/6400/1 "2016-10-06T21:59:49Z")

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Hello all,

I have a boat with a brushed series wound 36VDC motor, and I was interested in using a four-quadrant controller to provide seamless forward/reverse control with one stick and no switches.

I realize that these are designed for brushed PM motors, the controller can reverse the polarity to reverse the motor.

In a series motor, reversing polarity/direction must be done in the field or the armature, but not both.

So, I am hoping that I could use the four-quadrant controller’s motor output to connect to the armature1, armature2 back to the controllers other motor connection, then from the B- of the controller, go through the field winding and then return to the battery -.

This configuration would basically look like:

Battery + \> fuse/contactor \> controller B+ \> controller motor1\> motor A1 \>motor A2 \> controller motor2\> controller B-\> motor S1 \>motor S2 \> battery -.

What do you think? This would allow the motor controller to change motor polarity in the armature, but the field would stay the same, which would provide bump-less reversing. I am completely unconcerned with regen capability.

Many thanks for your advice,

Benjamin

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<div class="post-metadata">

**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\
**Post date:** [October 7, 2016, 6:03pm UTC](https://community.electricforum.com/t/series-motor-with-4q-controller/6400/2 "2016-10-07T18:03:09Z")

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[quote=nevbuggie;32885]Hello all,

I have a boat with a brushed series wound 36VDC motor, and I was interested in using a four-quadrant controller to provide seamless forward/reverse control with one stick and no switches.

I realize that these are designed for brushed PM motors, the controller can reverse the polarity to reverse the motor.

In a series motor, reversing polarity/direction must be done in the field or the armature, but not both.

So, I am hoping that I could use the four-quadrant controller’s motor output to connect to the armature1, armature2 back to the controllers other motor connection, then from the B- of the controller, go through the field winding and then return to the battery -.

This configuration would basically look like:

Battery + \> fuse/contactor \> controller B+ \> controller motor1\> motor A1 \>motor A2 \> controller motor2\> controller B-\> motor S1 \>motor S2 \> battery -.

What do you think? This would allow the motor controller to change motor polarity in the armature, but the field would stay the same, which would provide bump-less reversing. I am completely unconcerned with regen capability.

Many thanks for your advice,

Benjamin[/quote]

S1 and S2 can’t both be connected to B-. Battery- and B- is the same. 😕  
A pm motor would work or shunt wound.

Don’t try to invent something. Get an SX motor and controller.