Crystalyte Controllers - Repair and Modification information

After I switched from SLAs to a Yesa pack, my low voltage light in my throttle became useless because the Yesa pack voltage never goes low enough to trip it. While I'm saving my nickels for a Cycle Analyst, is there a way to modify my controller to adjust the low voltage warning?

Thanks,

-Cal
 
Yes. If you look toward the bottom of page 1 of this thread, you'll see the location of the low voltage cutout resistor. To get a higher voltage, you need a higher value resistor. Unfortunately, I never seemed to get that part of the circuit properly mapped out and there seems to be some variation between examples, so you may need figure out the right value.

If you take apart your controller and look closely at the resistors, you may be able to read off the numbers. From there we can make an educated guess as to the new value.

You could also replace the fixed resistor with a small trimmer pot to make the LVC adjustable. You will need to figure out a way to simulate the cutout voltage to test the circuit as well. A bench power supply is the best, but who has one of those? You could temporarily put a battery in series with the main pack *backward* to lower the voltage by a given amount. Even a small battery will be enough to test the LVC.
 
fechter said:
Yes. If you look toward the bottom of page 1 of this thread, you'll see the location of the low voltage cutout resistor. To get a higher voltage, you need a higher value resistor.
Cool! Thanks, fechter! I'll report what I find. It'll be my next project--right after I cut/thread 36 Sapim 12 ga spokes and lace up my new Salsa Gordo rim! :) My original rim supplied with my 5304 is cracking.

-Cal
 
Yes, you could power something off that. The pass transistor is good for a few amps and the controller is only using about 0.1 amps. It is a linear regulator, so it will waste most of the power and get pretty hot. If you take the (pack voltage-12v) x current= heat dissipated, you can get an idea of how hot your controller will get.

I'd recommend one of those switching power supplies with the wide range input or a dc-dc converter. Much less heat.
 
Thanks! good to know. I haven't found a switching DC-DC that would do up to 85 volts,function as low as 29 volts, and have an output around an amp. I figure I would have the controller feed an accesory battery, and run everything off that. Full current will only be needed a few seconds at a time.
 
anyone thought of using transient voltage suppressors to protect fets from voltage spikes, was some discussion on it for dual speed motors, but might make controllers less prone to fet damage
 
I'm not sure if they make them in the right voltage?

Anyway, it's better if your main capacitors are good enough that you don't need them. The energy can be recovered instead of dissipated.

You could get some benefit by adding super low ESR capacitors across the existing ones. Something like multilayer ceramic or polyester ones, less than 1uf. These can take up the very fast spikes better than the aluminum cans.
 
thats very interesting, so without removing the old caps you could add the 1uf caps?
so the function of the three caps on the fets is to dissipate the voltage spikes?? I never realised that was wondering what they were for!!!!
 
The main capacitors have to shuttle huge amounts of current back and forth. If they are undersized, they will heat up and sometimes explode. The aluminum electrolytics are pretty good at carrying the bulk of the charge, but they are not really good at very high frequencies.

Without the capacitors, the voltage spikes from the PWM switching would most likely destroy the FETs immediately. The batteries behave sort of like capacitors also, but their effective series resistance would be very high at the switching frequency, partly due to the inductance and resistance of the battery wiring.

I've had a couple of controllers where the main cap blew first, immediately followed by a FET failure.

Multiple smaller caps work better than one big one. More lead wires make for less resistance.
 
I alway like to read this part of the forum, thanks to all of you!
Last time you helped me with recognizing zenner diode 13V. Does any of you have a layout of other diodes on the board? I can provide the quality photos. I don't have the original controller any more so I'm unable to confirm what is zenner and what is only a regular diode. Most of them are in smd. I think those close to mosfets are also zenners. My cloned controller worked on lower voltage just fine but then one day blew and I need to get to the bottom of the problem.(building another 3!) That 13V zenner will definitely help. I didn't even use zenners close to mosfets and later on read somewhere in datasheet that zenners on the gate should protect the gate and are readily used there.As well as small 5-10 ohm resistors.(they protect the driver chip in case of the failure of the fets)
So if you have an idea what diodes are where I'll provide the photos. I'm still planning on drawing the schematics for all but recently I'm too busy with other projects. Also I'm not really sure that there really is interest for somebody to clone the controllers as I did. If I'm wrong let me know. (this may speed the schematics drawing)
 
Sure, post a pic. Most of the other diodes are just regular diodes. The larger ones are used in the driver bootstrap circuit. As I recall, the smaller ones are in parallel with a resistor to make the FETs turn off faster than they turn on.

Ah, here it is:
Brushless Controller Output stage.jpg
 
I've located some pictures from my pc of the original board.
Apart from bigger diodes that I can read and 1 smaller next to a big resistor that is 13V 1.3W zenner. There are 6 smd diodes (smd 4148?)paralel to 100ohm resistors going to 2n5551 as on your drawing. Then 1smd on the picture(unknown) and from the other side one smd called D4(unknown). All other parts I know. Thanks you!
 

Attachments

  • diode 1.JPG
    diode 1.JPG
    53.3 KB · Views: 6,590
  • diode4.JPG
    diode4.JPG
    77.9 KB · Views: 6,593
I can't get to the one on the bottom easily since the heat sink is back on.
The one on top measures like a regular diode. I'd give you 90% odds the one on the bottom is the same. Something with a 50v rating should be fine.
 
Thank You, I'll try to confirm this from the schematic when I finish it. Nemo
 
I'm wondering if anyone got their hands on the complete schematic for the controller?
 
here are the circuits for the 15V regulators used in the Crystalyte controllers. first the one used in the original analog controller.

15V REGULATOR.jpg

and now the switching regulator used in the newer V2 controller

Low Voltage Switching Supply.jpg

hope this helps.

rick
 
Thanks to fechter for this great thread, and for so generously sharing information. I've learned so much from all your knowledge this past year. It makes one appreciate the limitless possibilities of this hobby, with a better realized ability to tackle them.
 
D4 is a regular diode like a 1N914 or 1N4148.
 
Hmm today i decided to do some wire maintenance on my bike when i decided to mod the controller while i have it disassemble anyway. I notice the wires on the new crystalyte 72v 35A controller is puny. They're like 14guage wires. I think i'll up them to 12 or 10. As people have stated these are populated with IRF4310 so i'm going to replace them with IRF4110. Someone asked this before about this controller having 6 Mosfet even though it have 12 slots. I did a quick look and i THINK there is gate resistor connection already provided for the unpopulated spot. Anyone have different opinion? Do you think i'll gain any any benefit to adding 6 more? I need to know since i have exactly 6 IRF4110 left from other mod and i'm thinking of ordering more. Don't want to waste time and money is it won't make a diff. Thanks ahead for any reply. BTW it's the white PCB version.
 
ngocthach1130 said:
Hmm today i decided to do some wire maintenance on my bike when i decided to mod the controller while i have it disassemble anyway. I notice the wires on the new crystalyte 72v 35A controller is puny. They're like 14guage wires. I think i'll up them to 12 or 10. As people have stated these are populated with IRF4310 so i'm going to replace them with IRF4110. Someone asked this before about this controller having 6 Mosfet even though it have 12 slots. I did a quick look and i THINK there is gate resistor connection already provided for the unpopulated spot. Anyone have different opinion? Do you think i'll gain any any benefit to adding 6 more? I need to know since i have exactly 6 IRF4110 left from other mod and i'm thinking of ordering more. Don't want to waste time and money is it won't make a diff. Thanks ahead for any reply. BTW it's the white PCB version.

you are certainly better off with twice as many fets, whether they are 4310 or 4110. I have not seen the new controller yet, but i have a couple coming next week.

if you measure with your meter from the empty location's gate pin to the gate of the populated location you should see 20 ohms if there are 2 10 ohm gate resistors installed. i would not recommend mixing the 4310 and 4110, and the 4310 has a higher Miller charge than the 4110 so 2 4310's would need more drive current than 2 4110's, but if they are using the same boost circuit for the high side fets as the older controllers it should be fine with either part. If you are not running at over 50A you might keep the 4310s and just add 6 more of them. With 12 4110's i have quite a few controllers running around now set at up to 85A.
 
It's too late anyway. I already clipped off and desoldered the 4310. I was going to add the 4110 anyway. Just a decision of adding 6 or 12. I think the lower resistance of the 4110 is better since I'll be changing the battery wire and the motor wire to larger 10guage wires. This might result in higher potential current traveling through. At the same time I would probably use the same controller for 99v once in a while. So the robustness of the 4110 will help. This will be for the occasional speed fix.
 
Hi all, i'm just repairing a dual motor controller, that appears to use the 20A miniboard (6 fets). Although the controller appears to work OK, the motor wont spin up from all positions. Sometimes it spins, other times you have to roll it back to make it fire up. Any idea's?
Thanks:)
Steve
 
Jozzer said:
Hi all, i'm just repairing a dual motor controller, that appears to use the 20A miniboard (6 fets). Although the controller appears to work OK, the motor wont spin up from all positions. Sometimes it spins, other times you have to roll it back to make it fire up. Any idea's?
Thanks:)
Steve

That usually indicates one hall sensor is not working. Could be just a bad connection.
 
Hmm, wasn't halls sensors at all, and by the time we got through a batch of 10 controller repairs, we found this fault on 2 controllers. One thing that will cause it, is the gate leg of the mosfet not soldered in properly, another was a driver chip. Strange to see the same fault with 2 different causes...
Another symptom is slightly noisier running. (rumbles and such)
 
Back
Top