36volt scooter with 60volt Blast.

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1000WattZappyClassic
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36volt scooter with 60volt Blast.

I hooked up my scooter running 36volts on a 36volt controller and swithces to turn it off while riding and flip to 60volts! Is all hooked up but when i flip to 60volts the motor wires will still be connected to the controller and now the 60volts will be connected to the motor wires going into the controller. Do I need to hook up a switch do disconnect the motor wires too?

In other words, if you hook up a 60volt battery to the motor wires going into a 36volt controller, what would happen? Is it safe to do so?

e-doggies
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Re: 36volt scooter with 60volt Blast.

If I understand this correctly, you will be running 60V directly from the battery to the motor with no controller or throttle in the circuit?

1000WattZappyClassic
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Re: 36volt scooter with 60volt Blast.

Yes the 60 volts will run directly to the motor but will have a momentary switch for throttle/ to turn On/Off the 60volts to the motor. The 36volt controller will be turned Off while driving and the 60volts will be turned On.An visa versa But the motor wires will still be connected to the controller. Will this hurt the controller?

antiscab
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Re: 36volt scooter with 60volt Blast.

if the motor is brushed DC, then 60v direct will result in *very* strong acceleration. (and maybe a welded shut switch).

If the motor is brushless, then your wheel will lock up, and the switch will weld shut.
you will probably burn out your motor aswell.

In both cases, your controller will probably survive.
(even if the switching devices arent rated to the 75v or so they would need to be for a 60v pack, its the difference in voltage between the motor and battery sides that are important. so a power stage made of 40v components with 36v on the battery side and 60v on the motor side will be fine as the difference is only 24v).

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah
Vectrix 60Ah Lithium Tyres Fuel Registration Insurance cycle analyst 2 x TC Charger & MC
conversion

1000WattZappyClassic
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Re: 36volt scooter with 60volt Blast.

Of course it is a brushed motor. If it were a brushless, it would not run by connecting the battery directly to the motor.

If the switch welds shut, I CAN"T STOP! lol Even though it might not hurt the controller not to have a disconect switch for the motor wires, maybe I should hook that up also for saftey and to beable to stop the motor if the thottle switch welds shut. The throttle switch I was planning on using is rated 250volts 10amps. At 60volts the amp rating should be much higher. It might beable to handle the amp draw without welding shut.

Where can I get a momentary switch to handle it? I dont like motor controllers because they limit and hold back alot of power that the motor can produce. Unless I get a 100amp controller for my 32 amp motor, I would rather use a switch.

antiscab
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Re: 36volt scooter with 60volt Blast.

so we are talking about a brushed motor.

there are actually a few more problems you will encounter:
1) make sure your switch is rated for DC. a 250vac 10A switch will arc and wont be able to break a live DC circuit, even if it doesnt weld shut. this is made worse by the motor being inductive in nature. you need a DC rated switch rated to at least 100A at 60V (actually you need more than this if you want to be able to break the circuit reliably under load at low speeds).
2) such a switch is *very* expensive (though still not as much as a controller is)
3) you may encounter arcing on the brushes and commutator. this results in pitting of the commutator, which results in signifcantly increased brush wear, and eventually a fireball.
4) your battery may not stand up to the instantaneous high current draws on start up. What batteries are you using?

these things require more of a trial and error approach to determine the limits of each component (except for the switch and fuse, because manufacturers provide breaking capacity data).

do you own a controller at all at present? (i can describe how to crank up the amps on it)
if not, how much money are you looking to spend? (on either a switch or a controller?)

i agree that a gutless controller will hold back any motor.
a "real" controller should be rated to at least 3x what the motor is rated to
most controllers can be pushed harder for a short time.

you could try this for a controller:
http://www.kellycontroller.com/shop/?mod=product&cat_id=27,8&product_id=66

or if you would prefer a switch:
https://www.zeva.com.au/trading_post.php?id=21

that contactor will require a switch for the coil, but this can be a small toggle type one.
that contactor wont arc at anything like the current your setup could put out (its normally used in car traction circuits).

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah
Vectrix 60Ah Lithium Tyres Fuel Registration Insurance cycle analyst 2 x TC Charger & MC
conversion

antiscab
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Re: 36volt scooter with 60volt Blast.

some more data on common switch ratings:

most 250vac switches are also rated to 32vdc, at the same breaking current rating.
outside of these limits they arc, and cant break the circuit.
they also need to be derated when used in an inductive circuit (which a DC motor inherently is)

can you provide a link to the switch you intend to use? (or a picture if you already have it?)

another option would be a solid state relay (even more important to make sure its rated for DC, as the AC units cant be turned off when DC is flowing through them).
if you do go this route, make sure the switch is rated to at least the motor current at stall, otherwise it will fail short circuit.

you can add a sizeable capacitor to the motor side, to reduce the inductive kick while the switch is trying to open.
if you add enough capacitance to the circuit, a (mechanical) switch can be uprated.
again, you will have to find these limits by trial and error.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah
Vectrix 60Ah Lithium Tyres Fuel Registration Insurance cycle analyst 2 x TC Charger & MC
conversion

strawhistle
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Re: 36volt scooter with 60volt Blast.

speaking about your switch , a 120-250 10A switch will switch only 10A at60v or 10v , the amprage does not change! The amp flow is what creates the arc-weld . Any (stab) switch will arc because the initical contact is to the edge of the blade LaTeR

thank GOD I wake up above ground !!!!

1000WattZappyClassic
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Re: 36volt scooter with 60volt Blast.

Hey Matt thanks for your Help. How can I crank up the amps on my controller? It is the stock Currie 36 volt. Also can I run 48 volts to it without it burining out?

1000WattZappyClassic
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Re: 36volt scooter with 60volt Blast.

That 240volt 10amp switch is also rated 15amp 120volts so it does seem to raise in amperage rating if under less voltage.

antiscab
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Re: 36volt scooter with 60volt Blast.

you will have to open you your controller.

on the battery side, there will be a shunt, it will look like a resistor (or two of them in parrallel) in line with the big battery lines.
you need to solder a bit of wire in parrallel with the shunt.

NOTE: when solder the wire across the shunt, do it one strand at a time, and test max battery current everytime (and keep battery current lower than 1/3 of max component ratings, which we will work out below).

while you have it open, have a look at the part values and numbers (especially the FETs, which will be a row of 3 pin modules and the caps).
from that we can work out what the absolute max voltage the controller can accept is. It will also help us work out what the absolute max current the controller can do.

Matt

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah
Vectrix 60Ah Lithium Tyres Fuel Registration Insurance cycle analyst 2 x TC Charger & MC
conversion

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