99 ds plus obc bypass

[roundtable2]

I have read posts on bypassing obc, and understand to slpice blue and white wires with 10 amp fuse, and neg from charge receptacle to neg main battery.
I want to remove obc but worried about a yellow and green wire that routes from obc to controller and grey sense wire from charge receptacle to obc, Do I
just cut these wires and seal?
P.S. Yes I am buying a smart charger.

Thank You
Gary W.

[Sergio]

That is correct for the Regen-2 system, just cut and tape the yellow and green wires as they will not be used.

If you still have the OEM controller, You will loose the regen brake but the dynamic brake (solenoid with resistor coil) will still work.

[roundtable2]

Thank you sir, what about grey sense wire?, also it would be cool if we could get a schematic of obc and controller to design circuit to regain regen brake.

[Sergio]

The gray sense wire is not used by any smart charger so you can just disconnect it.

Another option if your powerdrive charger still works and you are keeping it, is to connect the gray sense wire from the charger receptacle to the pack negative as well.

That will allow you to use the old charger for backup purposes, just keep in mind it will never turn off automatically so you will need to manually unplug the charger when the pack voltage reaches 60v.

The Regen-2 was one of the transition models (short duration) and it has some unusual interfaces, but the OBC provided 13v on the green wire to the Controller when the batteries could accept a regen charge.

[roundtable2]

Thank you so much for valuable information, if I decide to analyze signals with my oscilloscope and implement a simple circuit, I will post findings,schematics,parts,testing results.

[Sergio]

Probably a simple 13v zenner (1N5350BRLG) and a 4.7k x 1W resistor inline would work for a simple 13v source from the 48v key switch power.

I think that controller only did Regen above around 9mph, below that it switch to dynamic brake anyway since there was not enough rpms for the motor to generate a higher voltage than the pack.

The new controllers short the armature briefly when at low speeds and then modulate (PWM) the quick energy buildup on the motor back to the batteries similar to how a buck converter works.

[roundtable2]

I was thinking op amp comparative circuit, But you are right zener diode much simpler. Interesting 4.7k ohm resistor, obvious controller uses miliamps for signal detection.

[Sergio]

Originally Posted by roundtable2

I was thinking op amp comparative circuit, But you are right zener diode much simpler. Interesting 4.7k ohm resistor, obvious controller uses miliamps for signal detection.

That is typically true on Curtis controllers.

I have done a few mods on my previous Excell controller between the speed sensor and the Controller to provide faster speed, I just used the outputs of an AVR microcontroller.

Keyswitch, fnr, speed sensor, lockout, etc are less than 10ma.