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Scoota series controllers.

Modification to regen brake circuitry.

There is a 'feature' on issue 1 and early issue 2 Sco-120 controllers where there can be a slight jolt just as the speed comes to zero. Most users do not even notice this - so it's severity is clearly a function of mechanical factors (motor, gearing, vehicle weight and speed).

However: the cure for it is quite simple, so we are releasing details here.

Controllers shipped from the factory after Oct 1st 1999 will already have been modified.

The effect is to do with the fact that the Scoota can be factory supplied with or without regen braking, so the hi-side drive circuit is modified slightly from, for instance, the Pro-120.

The drawing above shows the solder side of the issue 2 circuit board (30-31-02). The modification consists of linking out the base-emitter junction of a transistor in the hiside drive circuitry as shown.

It must be stresssed that this modification only applies to controllers which incorporate regen braking.

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