Crystalyte Controllers - Repair and Modification information

[fechter]

thanks for clarifying.. i though it was used to restrict power to the hub motor .. hmm i wonder if there is such a mod without having to purchase the cycle analyst ..

Yes, it's described earlier in this thread. By adding a pot and a couple of resistors, you can make the current limit adjustable. This will set the maximum power you can get.

[nemo]

Some time ago I showed here my first clone of the controller. Since then my friend burned his 72V/35A controller and I offered to maker him a new one.I took his burned one in exchange. Good swap? Well, I really felt bad that soon after making him the best scooter (with 40 A123...) the controller went.
Here is the picture of the new boards.

Other news:
IRFB4110 for UK
I finally got to call IRTronix and they are sold out on IRFB4110 now.
They will restock at the end of November .
I already ordered 150 with my credit card and the best price they gave me was 2.94. Normally $3.19 dollars.
With shipping to the UK the price will be about $500.
I'll also have to pay import tax/vat here in England (don't know how much it is ... lets say 20%).
Then 3% of total price extra for the credit card usage and some for bank currency change.
To sum up 300 pounds will cover about 150 mosfets.
I'll be re-selling them for 2 pounds each here in the UK so we can all have the chance to mod our controllers.
I want 48 fets, another 30 and 30 are already reserved for others who asked me some time ago.
42 are still available.
Let me know if You are interested in buying some. I might ever order more, if needed.
Thank You Pavel Nemo

[BiGH]

thats cool.

One thing i would be interested in is pre-modified 4110 controllers with adjustable (up to say 60-80amp) limits.

I think that would be rather cool.

[fechter]

That is cool. Do you have a schematic? If so, are you willing to share it? There are sections of the controller I never got around to reverse engineering.

[nemo]

Sorry, but I don't have schematics yet. Only BRD that I made in eagle 4.11.
It would be possible to draw the schematics from the BRD but it would take a long time and I'm too busy to do it right now.
Also, since I'm not a pro , BRD is good enough for me , but may not be the best for automatic brd. making.
But it is close to the original, even mosfets fits on the original alu cooling plate exactly. So the size/drilling etc. is the same.
Controller can fit in 4cmx6cmx18cm alu tube.
The total weight(including 30cm of wires) is only 500g instead of 1050g of the original controller. So you save 550g!
I also solder 3x 2.5mm3 coper wires on each mosfet bus as seen on the photo.And also where 3 phases are entering the PCB.
This coper weights over 30g! The clean PCB weights only about 25g!

On the board there are about 80 smd resistors, 16 diodes , most in smd, 10 transistors,12 mosfets and capacitors. It really takes a lot of time to build the controller and is definitely NOT cost efective (doing it at home).
Only perhaps if you like the chalenge to have your own controller as I do.

[steveo]

Low Voltage Cutout

The low voltage cutout circuit is designed to fold back the current limit when the battery voltage drops below a predetermined level.

The circuit consists of a voltage divider, a diode, and the comparator built into the PWM chip. When the voltage at the junction of the diode and R6 reaches about 3.8v, the diode starts to conduct and pulls down the input to the comparator, reducing the PWM duty cycle.

The resistors that make up the divider were difficult to read on my controller, and I was too lazy to unsolder them to measure the values.
I swear one of them looks like 104, which would be 100K, but that value wouldn't work against the 5.1k to get the right cutoff voltage.

If you snipped the resistor that has the switch across it, and put a potentiometer where the switch is, you could make the LVC adjustable.
I don't have known tested values for this resistance, so could only guess at this point.

Hey fechter

I've wired up the potentiometer to the throttle to have better throttle response and its working like a charm ; Just wanted to ask you which potentiometer would you suggest to use to adjust the LVC? i was thinking if i could use the LCV to set a limit as to how much can be drained out of lets say 2 packs of a123 cells w/o the board attached to the pack to limit the current (i don't know the name of the board of hand - but as per what i know it limits how much current can be sucked out from the cells; would this idea work as an alternative?

-thanks in advance
steve

[Antonio Zanardo]

I used to run a 408 motor with a 36-48 20A controller modified to work at 115V 20A. The bike performed very very well. High voltage, low amps is in my opinion the way to go. The benefits are lower current losses, thinner wires, small connectors and switches.

The mosfets I used are FDP2532 rated 150V 79A, but I had some problems with them, probably due to excess current (or voltage?) spikes.
I wonder if I can stack two mosfets of that type by paralleling them pin to pin, and if the twin ones behave just like one. Should I expect from the mosfet pair double current, half on resistance, double input capacitance?

The stock controller has only 6 mosfets, so I would arrange the new 12 mosfets on two 6 unit strings placed on a separate board.
Each string would have its buss bars interconnected to the other string in order to paralleling mosfets, and each string would have its proper heat sink.

The power and motor cables would be soldered to the new board which contains the mosfets, therefore the connections to the main board would be limited to to some low power and signals wires.

What should I expect from this arrangement? I would be happy if the on resistance of the coupled mosfets is cut in half, but worried if the input capacitance gets twice as much!

Any comment/suggestion will be greatly appreciated.

Antonio Zanardo

[solarbbq2003]

i was messing with low voltage cut off in a 36v/48v 20amp crystalyte controller ( oder version ) the other day.
Wanted to run on 24v.
The resistor r3 is 33kohhm, I put a variable resistor in parallel with r3 to adjust low voltage cut off. One measurement i took was a 61k in parallel with r3 ( 33k) will make the cutoff 20volts.
But if wanting to use for 24v system, and not worried about what level is the low voltage can throw in anything under 61k, I went down to 68ohmn in parallel with r3 and controller still worked.
From a very old bit of info off old crystalyte site values to use as follows:
( this is replacing r3 with new resistor value)
75k = 62v cut off
68k = 58v
36k = 31.5v ( but there was a 33k in the controller giving 31.5v cut off anyhow)
Also i'm not really sure if there is much practical value in low voltage cut off.
If using sla batteries you will know way way before 10.5v per battery that the batteries are flat, batteries will still be over 12v and feel flat as can be.
Might be useful if controller is left on for a long time to stop complete drainage of batteries though, but I dont see much value in low voltage cut off.
( antonio I cant help with your question!!! I've paralleled fets before and its worked is all I can say on that)

[The7]

The original 48V IS controller has an LVC at 29V.

The 33k and the R6(5.1k) will be removed to de-activate the LVC so that the controller will work from 24V battery to 48V battery for my AL1020 ebike.

Please see the diagram in my previous post:
http://endless-sphere.com/forums/viewto ... c&start=90

[fechter]

I wonder if I can stack two mosfets of that type by paralleling them pin to pin, and if the twin ones behave just like one. Should I expect from the mosfet pair double current, half on resistance, double input capacitance?

The stock controller has only 6 mosfets, so I would arrange the new 12 mosfets on two 6 unit strings placed on a separate board.
Each string would have its buss bars interconnected to the other string in order to paralleling mosfets, and each string would have its proper heat sink.....
What should I expect from this arrangement? I would be happy if the on resistance of the coupled mosfets is cut in half, but worried if the input capacitance gets twice as much!

Any comment/suggestion will be greatly appreciated.

Antonio Zanardo

Yes, you can parallel the FETs as long as each one has its own gate resistor. Do not put the gates in parallel directly. The gate resistors should be at least 10 ohms.

The gate capacitance could be an issue depending on the drivers, but based on our combined experience here, you can increase the capacitance quite a bit without causing switching speed problems.

Doubling the FETs will cut the on resistance in half. As long as the switching speed stays fast, the heating will be about half as well. I think current spikes are responsible for most failures, so with twice the current capacity, reliability should be improved.

Go for it!

[Antonio Zanardo]

Go for it!

Thank you Richard! I'll give it a try.
Would you suggest to place some clamp diodes on the second board close to the mosfets, as I have some space available? If so, which diode part # would be suitable?
Thanks again.

Antonio Zanardo

[fechter]

I wouldn't bother with clamp diodes. A second large capacitor(s) across the power rails would be good.

[rsisson]

Apparently my crash did more damage than I thought. Got the hall effect wires fixed powered it up and it seemed ok, motor runs...

Put it on the Ground, apply power and THUNK on power up, and nothing more. It just goes THUNK, and then nothing...

Ok, this is obviously NOT a warranty issue, so I open the controller. Oh, Oh, I fried two surface mount resistors and a fet or so... but good...

Whats interesting is my board looks NOTHING like the boards posted earlier.

Looks like it has room for another set of FETs... no connectors... and lots of other changes ....

I have ordered a NEW controller as I can't see well enought to work on things like this anymore... who might be able to repair this one for me?

[fechter]

I'm pretty busy lately, but it looks like it would be interesting (translation: it would take a long time).

Bob Mcree or Lowell might be able to help.

[Brucey]

Hay rsisson, welcome to the club!

I've had 1 Motor blow, and 2 controller blows since august.

My bikes ran a week since I paid for it!

Same style controller as yours though.

(By the way, 2010 sucked, don't watch it.)

[fechter]

It looks like the same FET that blew. Just coincidence?

They changed the design, but it seems like it's not really better (probably cheaper to make).

Somebody's going to have to try loading up one of those with 4110's.

You might be able to get away with just cuting off the stock fets with clippers and installing six 4110's in the empty holes. I wonder if the empty holes have gate resistors installed?

[Jozzer]

Which controller are these? I hope they arn't the new ones Justin has...

[Brucey]

Mines the brand new 72V40A from poweridestore

I'm considering replacing the fets and giving my ebike one more chance (see for sell if you want the full story on that)

[Jozzer]

Can anyone confirm if these are the same as Justins new controllers?
Seems a bit strange they replaced 12 half arsed fets with 6 fully arsed ones so to speak...

[rsisson]

I think they are BOTH the crystalyte 4850 (4840) controllers with the 07-5-11 date code.

[GGoodrum]

Geez, this is confusing. Do both of these have the extruded cases, or the regular square ones? The extruded versions (with the fins...) are a bit narrower and longer than the original rectangular cases.

-- Gary

[Brucey]

mines the newer design with the fins.

[rsisson]

Mine too has fins on the FET portion of the enclosure.

Looking at the rough circuit design posted in the section, if a FET dies, unless it dies OPEN which apparently is rare, it provides a direct short to the Rail, which invariably will take out the OTHER FET or two.

Is there any way to Protect the FETs from self destructing? Obviously it would need to be just as fast as the FET....

Looking at lots of other FETs, do we NEED the speed, or just the Low Rds. The Low Rds keeps the power dissipated by the FET down, but I would be willing to give up some of that for Robustness.

IR makes some "Fully Protected" MosFets http://www.irf.com/whats-new/nr070123.html that have a higher Rds, but might survive what we attempt to do...

The other option is to go with some seriously over sized devices in a True POWER configuration in another package, like the ISOPlus-227 from http://www.ixys.com/powerproducts.html or http://www.st.com/stonline/products/lit ... 80ne10.pdf

[Jozzer]

Hmm, I mailed Justin, he said..
"All of the 40A controllers we have have 12 mosfets, either 12
IRFB4110's as the option or 12 IRFB4310's as the stock.

The controllers with the 4110's are the old style analog circuit. The
72V 40A stock controllers are the newer style with a microprocessor.
The 36V 35A controllers are the old style.

Justin"
Seems like they are completly different from the powerrider ones?

[rsisson]

Ok, where do the crystalyte 4850 (4840) 6-FET controllers fit in the life cycle?