I am out of the office. Since my only office companion is my cat; you will have to wait until I get back to ship your order. I will ship orders on Monday_April_10th Cheers!

used SEVCON Gen4 Size4 72/80V 350A SIN/COS-UVW-ACI controller PN 634A83203 100V S4

Sale price $300.00 Regular price $975.00

I have two (2ea) available, price is for each. See the part number / SN / hardware number in the photos. If you have a preference as to which one you want let me know.

I want to be of service since I have a copy of the DVT software but this is limited because often the controller needs to be match to the motor. I have the newer firmware version updates if you prefer a particular version. I have versions 0705.0012, 0705.0013 and 0705.0014 which I can upgrade it before I ship it.  If you want me to try to pair the motor for you then send me a message. Be aware I have limited experience pairing to motors but I will help as much as I can.

This controller will work on the Zero motorcycle if programmed with a back of your old unit. I do have a backup of a Zero motorcycle if you would like to me to load it.

I have third one that is not working (contact welded error), if you want one for parts then message me directly with an offer.

If you are not familiar with these units than it is important to know that you need licensed DVT software from Sevcon to program these units and the software costs about $800. Alternatively you can rent the software from Thunderstruck.com / electricmotorsport.com OR you can hire them/others to program it.

If you knew the above then you already know what this is and there isn't more I can tell you other than I bought it used for a project but I ended up going with a 550A version so I am looking for a good home for this one.

*** note that this controller will work for a 100V system since its operating voltage goes up to 120V so it will work on a 28cell system

Nominal Voltage
72 - 80 - 100 VDC
Operating Voltage
39.1-120 VDC
Current (120s)
Boost (10s) 420A



- Advance flux vector control
- Autocheck system diagnostic
- Integrated logic circuit
- Hardware & software failsafe watchdog operation
- Supports both PMAC motor and AC induction motor control
- Integrated fuse holder
- IP66 protection

Multiple Motor Feedback Options

Gen4 provides a number of motor feedback possibilities from a range of hardware inputs and software control, allowing a great deal of flexibility.

- Absolute UVW encoder input 
- Absolute Sin/Cos encoder input 
- Incremental AB encoder input

Integrated I/O 

Gen4 includes a fully-integrated set of inputs and outputs (I/0) designed to handle a wide range of vehicle requirements. This eliminated the need for additional external I/O modules or vehicle controllers and connectors. 
- 8 digital inputs 
- 2 analogue inputs (can be configured as digital) 
- 3 contactor/solenoid outputs 
- 1 encoder supply output

Other Features

- A CANopen bus allows easy interconnection of controllers and devices such as displays and driver controls. 
- The CANbus allows the user to wire the vehicle to best suit vehicle layout since inputs and outputs can be connected to any of the controllers on the vehicle and the desired status is passed over the CAN network to the relevant motor controller. 
- The Gen4 controller can dynamically change the allowed battery current by exchanging CAN messages with a compatible Battery Management System.