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I was contemplating these controllers before they released the 500 amp version. I'd love to know more, since I'm considering another low budget conversion, and this looks like a great match.

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Damn that's cheap.

That's tempting.

I was contemplating these controllers before they released the 500 amp version.
Well it's low cost and Chinese, so, based on experience, do you know what the difference is between the 350A and the 500A controllers?

The label. They shuffled the 50 from the 350 over, and turned the spare 3 into a zero. Ta da. Modifications complete. 500A!

Though but seriously, if it works it's a good price, if it doesn't work it's a shit price.
 

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I've been trying to run the 200V 70A controller and it has had issues. Balint has been very good at responding and helping troubleshoot. I'm hoping we can get it worked out. It seems to be well-made.
 

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Well it's low cost and Chinese
Seller is from Hungary

Anyone comment on the use of electrolytic capacitors ? paralleling them up will reduce the ESR considerably so the theory is on it working, also those transistors will need to be bolted to some serious metal to keep them cool
 

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As I said it looks just like the Paul & Sabrina 500 amp DC controller

Which works very well indeed and was done as an open source project

The Mosfets are bolted to a big lump of aluminium

From the sounds of it they are using a different "brain board" but the power electronic bits look similar

Here is a link to the thread

https://ecomodder.com/forum/showthread.php/paul-sabrinas-cheap-diy-144v-motor-controller-6404-3.html

It's very long but worth going through before spending any money

The P & S Kit is about $500 - and can be constructed by a complete beginner ! (I know)

Question for electronic types - this uses an Arduino - I have an idea that was a bad idea because of susceptibility to noise?
Is that correct?
 

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The Arduino is just a development board that uses a ATMega328 micro controller at its heart, using the Arduino board in a production system would be far from ideal for noise.

The ATMega328 which is the brains of the Arduino is however a fine chip and perfectly adequate for a DC/PWM controller in a properly designed board, noise is more a product of design/and PCB layout not the micro controller and this design looks quite neat without knowing the technicalites.

The dsPIC used in other DC and most AC Controllers has much more processing and dedicated hardware for multi-channel PWM plus it has lots of application notes to help roll your own design.

If Paul's design is open source then this is one of the things that happens if your design is good, Paul would be aware of this when he released it into the community though I dont know the specific Open Source Licence he uses to comment on whether he allows commercial use.

Open sourcing designs does however overall make the world a better place in my humble opinion.
 

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Hi there people.
I found this controller on ebay. It looks like the perfect deal for my low budget conversion using a 80V forklift motor. But i cant find any feedback.

Is there someone in here who have bought and used it?

https://www.ebay.com/itm/183161460170?ul_noapp=true
To properly choose a speed controller you need to know the amperage rating of the motor (peak and constant).

If that info is not available then, you need to find/figure out the internal resistance of your "particular" motor, just measure it with a multimeter.

The lower resistance value is the one you want (you may have to turn it slowly by hand while measuring) because sometimes the commutator is not in perfect contact and by turning will find you the best spot [least resistance])

Then, divide 48 by that number and you'll get the max amperage

You'll get the MAX rating not the constant rating, but you can choose the controller by that number if you overestimate by about 15% safety margin.
(say max amp is 320Amps calculated.. pick a 370Amp max rated controller or bigger.)

The "proper" controller (for your motor) will be able to provide all the amperage you need at a constant rate.
(keep in mind that the max rating is likely in the name of the controller.. which is about three times it's constant rating)
 

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To properly choose a speed controller you need to know the amperage rating of the motor (peak and constant).

If that info is not available then, you need to find/figure out the internal resistance of your "particular" motor, just measure it with a multimeter.

The lower resistance value is the one you want (you may have to turn it slowly by hand while measuring) because sometimes the commutator is not in perfect contact and by turning will find you the best spot [least resistance])

Then, divide 48 by that number and you'll get the max amperage

You'll get the MAX rating not the constant rating, but you can choose the controller by that number if you overestimate by about 15% safety margin.
(say max amp is 320Amps calculated.. pick a 370Amp max rated controller or bigger.)

The "proper" controller (for your motor) will be able to provide all the amperage you need at a constant rate.
(keep in mind that the max rating is likely in the name of the controller.. which is about three times it's constant rating)
There is not a single thing correct in this answer - best to ignore it
 

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Looking at my controller, I don't see any obvious current sensor. Mine is also quite destroyed, so there could have been a shunt or the like there. I've attached some pictures.
 

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There is not a single thing correct in this answer - best to ignore it
Really! Don't just dispute it, please explain what's NOT correct.

To clarify, the only thing NOT 100% correct Is where I said "divide 48 by that number"
(I was working with a 48VDC system, at the time)
I should have said "divide your intended voltage by that number"



"The controller is picked BY the current a motor could draw
since what the motor COULD draw is exactly the amount the motor WILL draw if it needs to.

You want a controller_continuous_ rating that's sufficient for the motors _continuous_ rating.. when in doubt
(since the motor's power thirst can easily boil a controllers internals)
scale up so that the controllers _continuous_ rating matches the motors _MAX_ rating."

* In a nut shell, you want a speed controller with a constant amperage rating that matches or slightly exceeds the motors max amperage rating.

I learned that from my buddy Sid.
 

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Really! Don't just dispute it, please explain what's NOT correct.

To clarify, the only thing NOT 100% correct Is where I said "divide 48 by that number"
(I was working with a 48VDC system, at the time)
I should have said "divide your intended voltage by that number"



"The controller is picked BY the current a motor could draw
since what the motor COULD draw is exactly the amount the motor WILL draw if it needs to.

You want a controller_continuous_ rating that's sufficient for the motors _continuous_ rating.. when in doubt
(since the motor's power thirst can easily boil a controllers internals)
scale up so that the controllers _continuous_ rating matches the motors _MAX_ rating."

* In a nut shell, you want a speed controller with a constant amperage rating that matches or slightly exceeds the motors max amperage rating.

I learned that from my buddy Sid.
Tell Sid he does not have a clue either


The controller is picked BY the current a motor could draw
since what the motor COULD draw is exactly the amount the motor WILL draw if it needs to
.
BOLLOCKS - at 48v and zero rpm something to the north of 4000 amps will flow through my motor - the sustainable current is 200 amps

In a nut shell, you want a speed controller with a constant amperage rating that matches or slightly exceeds the motors max amperage rating.

Bollocks again - I'm using a controller that will supply 1200 amps - SIX times the motors max sustainable current

Please STOP feeding misinformation to people who want help
 

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Great deal or scam? is the question.


I'd say it's neither. Just from the pictures I have reversations about the low cost trimpots, the way the bars are screwed on (screw type and washer) and the isolation pads (if they are indeed what I think they are).


The warranty period and price reflect the quality, I guess.
 

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Tell Sid he does not have a clue either


The controller is picked BY the current a motor could draw
since what the motor COULD draw is exactly the amount the motor WILL draw if it needs to.
BOLLOCKS - at 48v and zero rpm something to the north of 4000 amps will flow through my motor - the sustainable current is 200 amps

In a nut shell, you want a speed controller with a constant amperage rating that matches or slightly exceeds the motors max amperage rating.

Bollocks again - I'm using a controller that will supply 1200 amps - SIX times the motors max sustainable current

Please STOP feeding misinformation to people who want help
Overcompensating due to a lacking elsewhere?

You sound like someone who put a big block 454 in a little Chevy Vega & says "I know what I am doing because I can go really fast"



Well, I asked my buddy Sid to explain the concept to me a bit more so that I can share & explain it better to you guys:

"Hey Sid,
I got a quick question.
Remember when you taught/explained to about matching a speed controller to a motor by finding the internal resistance?
What is that method called or referred to?
Can you give me a link to this info?

Thanks, Kevin"

(His response)

"Common sense I guess.
No, I don't have a link for you I'm afraid..

You'd need to wiggle your way through some physics classes/websites if you need that info verified.

Idea is simple and straight forward:
"unknown" current draw for a known Voltage motor
is simply based on the Ohm's Law (URI) triangle (R= U/I.. resistance = voltage per amp)
rearrange to get U/R = I and with known voltage(U) and known resistance(R) you get the maximum amperage(I) the motor is able to draw.
(in english it'd be VRI but other than a letter change the rule's the same)

then just add a bit to compensate for measurement error and thermally induced resistance changes
and get the U*I Wattage motor controller (continuous draw, not peak to play safe)

That's all there is to it.. very basic physics actually,
with some common sense as an adjuster.
since the controller cannot harm the motor by being capable of delivering more amps, you can scale that up to your liking but you should at least compensate for false readings or possible changes in internal motor resistance just to not pop the controller with a too hungry motor.

I bet you can find similar thoughts on numerous websites.. I just don't know any from on top of my head.

'sid"
 

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Overcompensating due to a lacking elsewhere?

You sound like someone who put a big block 454 in a little Chevy Vega & says "I know what I am doing because I can go really fast"



Well, I asked my buddy Sid to explain the concept to me a bit more so that I can share & explain it better to you guys:

"Hey Sid,
I got a quick question.
Remember when you taught/explained to about matching a speed controller to a motor by finding the internal resistance?
What is that method called or referred to?
Can you give me a link to this info?

Thanks, Kevin"

(His response)

"Common sense I guess.
No, I don't have a link for you I'm afraid..

You'd need to wiggle your way through some physics classes/websites if you need that info verified.

Idea is simple and straight forward:
"unknown" current draw for a known Voltage motor
is simply based on the Ohm's Law (URI) triangle (R= U/I.. resistance = voltage per amp)
rearrange to get U/R = I and with known voltage(U) and known resistance(R) you get the maximum amperage(I) the motor is able to draw.
(in english it'd be VRI but other than a letter change the rule's the same)

then just add a bit to compensate for measurement error and thermally induced resistance changes
and get the U*I Wattage motor controller (continuous draw, not peak to play safe)

That's all there is to it.. very basic physics actually,
with some common sense as an adjuster.
since the controller cannot harm the motor by being capable of delivering more amps, you can scale that up to your liking but you should at least compensate for false readings or possible changes in internal motor resistance just to not pop the controller with a too hungry motor.

I bet you can find similar thoughts on numerous websites.. I just don't know any from on top of my head.

'sid"
Just STOP spreading misinformation
SID is completely WRONG and neither of you have a single clue

Just STOP

Your calculation will yield the absolute maximum current that can be pushed into a stationary motor
That number is completely USELESS for anything
 
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