Removing Magnetic Braking

[Rye]

For anyone who has removed their magnetic brakes, have there been any control issues and has their been any significant battery savings? I'm trying to slime line my chair by reducing weight and by removing all possible non-drive battery drain.

[jeffreyclay]

I had a wire break that operated one of the brakes and the controller (P&G VR2) saw it as a failure and wouldn't let the chair operate. The brake doesn't weigh much, maybe 8 oz. Mine have a DC resistance of around 55 ohms so on a 24v chair that would amount to 10w for each brake. I've no idea how much you could raise that resistance to lower your current consumption before the controller sees it as a failure state. You might experiment with a 200 ohm rheostat in place of a brake coil and see how high you can go before it fails. 200 ohm would cut your consumption to 2.5w. It that example worked you would replace your brake with a 200 ohm 5 watt power resistor (1oz). Hope this helps. Jeff

[Rye]

I had a wire break that operated one of the brakes and the controller (P&G VR2) saw it as a failure and wouldn't let the chair operate. The brake doesn't weigh much, maybe 8 oz. Mine have a DC resistance of around 55 ohms so on a 24v chair that would amount to 10w for each brake. I've no idea how much you could raise that resistance to lower your current consumption before the controller sees it as a failure state. You might experiment with a 200 ohm rheostat in place of a brake coil and see how high you can go before it fails. 200 ohm would cut your consumption to 2.5w. It that example worked you would replace your brake with a 200 ohm 5 watt power resistor (1oz). Hope this helps. Jeff

I have a programmer and was able to shut the brake inhibit off. I just realized I can now just release the brakes and find out how it handles. I'll report any issues.

[Burgerman]

The brake does not brake you. It just stops you AFTER you stop the chair. So it cannot affect how anything handles. What you will notice is that if you release the stick, it will roll away down a ramp or hill slowly.

[Rye]

Yes, I know it doesn't slow the chair. Ain't too many hills around here. I have, however, decided against doing it to all my chairs because I may need them brakes when driving! I have an older chair though that stays at home and gets pretty muddy all the time.

[Burgerman]

I leave mine powered as normal. Then disconnect the freewheel microswitch and join the wires. Then the chair either has brakes and goes click click, Ot not, when I flip the freewheel lever.

[ex-Gooserider]

As others have said, the controller will shut you down if it doesn't 'see' the brakes - however this MAY be something that can be changed with an OEM programmer, as some have settings for whether or not brakes are installed....

If you don't (or can't) fix it in programming, then you will need to substitute a power resistor in place of the brake coil... You can probably use a larger value resistor than the actual coil resistance (experiment as suggested earlier to see how high a value you can use and still fool the controller) but you will still have some current draw, so you may save the very small weight of the brake coil, but won't reduce your power draw by much...

BM's suggestion of playing with the freewheel switch might or might not work depending on your motors.... Some motors do free-wheel by holding the brake open, and requiring you to spin the motor to push the chair (which makes it hard to push!) and these chairs need the switch to disable the controller so you don't go driving with no brakes... Bypassing the switch lets you continue to drive with the brakes locked open....

Others do freewheel by disengaging the gears in the drive box, which makes the chair much easier to push as you aren't having to backdrive the motors... These often don't have (and don't need) the brake disabling switch since the motors are disconnected from the drive wheels - run them all you want. you aren't moving under power.... BM's switch trick won't work on these...

ex-Gooserider