two kollmorgen 400w motors one 5k pot?

8 posts / 0 new
Last post
noobster
noobster's picture
Offline
Last seen: 15 years 4 months ago
Joined: Friday, May 16, 2008 - 20:11
Points: 45
two kollmorgen 400w motors one 5k pot?

So I've bought all the parts for my twin 400w kollmorgen electric bicycle project. I've received the motors but the rest of the parts are on the way. Aside from a new rear wheel to mount on the front fork (fwd) the only thing I did not purchase was a throttle. I need to run both motors evenly but both require a 5k pot.
1) Can I run two of these motors(controllers) off a single 5k pot?
2) If not does anyone know of a source to find a dual 5k pot(six wires, two pots connected on a single shaft)?
3) Will a pot with ohms over 5k work?
4) The professor at the college's electronic department, I go to, told me about voltage controlled pots for a more accurate equalization of both motors. Does anyone know where to purchase them? I stumped the guy at radio shack with this and all these questions, it was funny.

I've used this site A LOT while researching how I was going to go about building my bike and my plan actually evolved two or three times for the better because of you guys. This is my first actual post on the forum but not the last. Thanks. -Ryan

LinkOfHyrule
LinkOfHyrule's picture
Offline
Last seen: 14 years 9 months ago
Joined: Wednesday, October 17, 2007 - 14:54
Points: 730
Re: two kollmorgen 400w motors one 5k pot?

Yeah, you can.

I've seen dual linear 5k pots, but only as a part; I've never seen a dual 5k throttle.

Three wire pot throttles typically work as voltage dividers. With suitable current and voltage levels coming from the controller, any pot would work. However, since the current from the Kollmorgen controller's throttle out is limited, higher than 5k wacks out the throttle response. Less than 5k and more voltage from the + throttle lead gets leaked into the ground of the lead, meaning you won't ever be able to go full throttle. In short, only a 5kΩ 3 wire resistive throttle will work on a Kollmorgen without modification.

DigiKey probably has them (they have like everything), but that's overkill. Since the Kollmorgens are designed to work properly with a 5% tolerance on the throttle, it shouldn't make any difference in the throttle response.

To actually run them off one throttle is simple: Hook the throttle up to one motor as you would normally, and connect an extra signal wire to the second controller. Note that while this should work in theory, I have not tried this. If you want I have four Kollmorgens lying around doing nothing. I could try it out if you want.

Welcome, BTW. :)

The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai

e-doggies
e-doggies's picture
Offline
Last seen: 8 years 8 months ago
Joined: Sunday, December 30, 2007 - 10:15
Points: 290
Re: two kollmorgen 400w motors one 5k pot?

To actually run them off one throttle is simple: Hook the throttle up to one motor as you would normally, and connect an extra signal wire to the second controller. Note that while this should work in theory, I have not tried this. If you want I have four Kollmorgens lying around doing nothing. I could try it out if you want.

I have two brand-new Kollmorgens and am interested in putting dual motors on a scooter. Was hoping to hook them to one common 5K throttle, but unsure of the wiring. So, if you'd be willing to do a quick test, there's likely at least two of us that would be interested in the results. Thanks.

Harlow

noobster
noobster's picture
Offline
Last seen: 15 years 4 months ago
Joined: Friday, May 16, 2008 - 20:11
Points: 45
Re: two kollmorgen 400w motors one 5k pot?

*"digipot" not "voltage controlled pot" is what the teacher meant, I think*
Thanks for the test work. I would try but I don't know a lot about electronics and even less about how to fix them if something inside the controller were to burn up. This is asking a lot but if you could let the motors run for a while maybe even with some load, so as to rule out the possibility of them "eventually" frying. Anyways... Much Thanks. -Ryan

go green

andrew
andrew's picture
Offline
Last seen: 14 years 2 months ago
Joined: Tuesday, November 28, 2006 - 17:21
Points: 1361
Re: two kollmorgen 400w motors one 5k pot?

If it doesn't work there's one at the bottom of the page here:
electricscooterparts.com - Throttles

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

noobster
noobster's picture
Offline
Last seen: 15 years 4 months ago
Joined: Friday, May 16, 2008 - 20:11
Points: 45
Re: two kollmorgen 400w motors one 5k pot?

That's a dual pot and exactly what I need thanks.

go green

noobster
noobster's picture
Offline
Last seen: 15 years 4 months ago
Joined: Friday, May 16, 2008 - 20:11
Points: 45
Re: two kollmorgen 400w motors one 5k pot?

So I got the dual pot and it worked fine. I got crazy one late night and tried it on one pot and it worked too. Now I'm running one magura 5k twist throttle for both motors and it works fine. Just thought I'd let you all know. -Ryan ps: check out my site about my bike, electricky.googlepages.com (no www.).

go green

monty
Offline
Last seen: 14 years 4 months ago
Joined: Tuesday, November 10, 2009 - 22:06
Points: 5
Re: two kollmorgen 400w motors one 5k pot?

hi i just bought a kollmorgen 300w motor with built in speed controller and have wired it up like the diagram says but it doesnt work could anybody please give me a hand with this thanks
monty

Log in or register to post comments

Use code"Solar22" and enjoy 12% off for all solar Kits.


Who's online

There are currently 0 users online.

Who's new

  • xovacharging
  • stuuno
  • marce002
  • Heiwarsot
  • headsupcorporation

Support V is for Voltage