# Does anyone have experience with Sevcon controllers?



## Wirecutter (Jul 26, 2007)

I'm not experienced with _that particular_ controller, but I've got a Sevcon in one of my gokarts. The model I have was built custom for use in a tiny pickup truck type of thing used to get around warehouses and such.

Sevcon and Navitas both do a lot of this kind of thing - making variations of standard products for an OEM customer. When I made inquiries, I got absolutely NO traction from Sevcon. I also have a Navitas controller like this. Navitas didn't completely blow me off like Sevcon, but they did politely explain that they are bound by contract not to reveal any info about that particular model. One guy even encouraged me to try to hook it up and get it to work.

Sounds like you have an "in" - you can determine how it was hooked up and do the same. Generally, Sevcon and Navitas seem to make nicer controllers, albeit more expensive ones. The Sevcon in my gokart drives a SepEx motor and features regen braking, contactorless reversing, reverse speed limited to 1/3 power, and "nice" acceleration curves. (That last part is kind of annoying - I actually want the gokart to snap my head back, but that's not a good thing in an industrial vehicle.) I got it used - otherwise I wouldn't have paid a premium for the features and brand just to put it in a gokart.

I say go for it. Let us know how it works for you.

-M


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## Tubularfab (Sep 25, 2008)

I found an old data sheet on the tractor this controller would have been from - the model number on the controller was Sevcon SC2000, and it was rated at 1000 amps total.

I do remember there being a little handset programmer for the controller, but I don't remember what all it let you tweak. I do remember there being a value for acceleration that was number of seconds to ramp from 0 to full power. You could set it for .1 and the thing would immediately pull in the bypass contactor launching the 7000lb tractor into a serious wheelie! Seems like it had a lot of settings for the regen in there as well. I guess I'll just have to get it and see what all it has! I should still have a wiring diagram somewhere for it.

Oh, and it is a complete panel with all the contactors already installed and wired mounted to a thick aluminum heat sink panel. It probably measures about 24" x 24". So, all I will need is to run power into it and out to the motor - the rest is already there.


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## Tubularfab (Sep 25, 2008)

Ok, found a list of the variables accessable from the programmer, and these do seem familiar now:
Imax, Accel, Decel, creep speed, max speed, cut speed 1/2, cut accel 1/2, dir. brake, ntrl brake, foot brake, bypass out, F.W. in, F.W. out, steer delay, seat delay, regen speed, brake const, accel zero, accel full, brake zero, brake full, econ zero, econ full, str left, str right, steer factor, dead band, byp. relay.

Unfortunately the list of descriptions is all in another language, but the names are pretty descriptive anyway. Looks like the controller is pretty versatile! I had forgotten that it would turn the power steering pump on and off automatically when you started to drive it.


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## GizmoEV (Nov 28, 2009)

I know this is an old post but did you get any info on your controller? I have a Sevcon PowerPack PP745 and some documentation on it and some experience with the different parameters. If you are still trying to figure some things out let me know and I'll try to help out.

David


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## JeanChasseur (Sep 24, 2014)

Hello SEVCON gurus!

I am FINALLY pulling all the pieces together for my EV Porsche Boxster, having JUST acquired the donor vehicle 3 days ago. I opened up the eBay EV-special box of parts which I acquired 18 months ago which includes a D&D SEPEX motor and a SEVCON PP745 SEM controller. I set up everything on the bench and got several fault codes before figuring out the sequence of events and switches to get the SOLID Green light on the controller.

I haven't had success getting the motor to spin yet, but that may be because I am using daisy-chained power supplies (batteries arrive tomorrow) and that D&D really draws a lot of current.

I HAVE NO IDEA how the PP745 (firmware Version 4.50) is programmed or where it came from, DOES ANYONE KNOW WHERE can I rent or borrow a Sevcon SC2000 Calibrator?? I saw one on eBay for $500, but I can buy a new Alltrax DCX controller for that kind of money for something I will likely use just once!

Thanks a million in advance!


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## GizmoEV (Nov 28, 2009)

Do you have the manual? I've attached a copy to this post. You will have several parameters to set like the current range of the field and armature. Also, throttle input values need to be set including the max & min voltages of your pack. The controller can control a 24V or pack voltage contactor. I ended up using a 40A automotive relay with a 24V coil and then it controls my main contactor. I had to do this because of the current draw of my contactor.

Some settings affect what other settings are available. If you can find the software that someone on this list was working on a few years ago that might be the best route to go. IIRC, it would display all the parameters at once. I have not had the time to check it out and since I have a calibrator that works with my older controller firmware I didn't have too much of a drive to do so. It is unfortunate that my calibrator can only read what is already set in your controller otherwise I could loan it to you.


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