[Ziggythewiz]

I don't see why the resistor would have failed. It should be passing 6 mA continuous, not enough to damage it and likely not enough to feed the DC-DC and the controller caps.

[major]

Originally Posted by Ziggythewiz

I don't see why the resistor would have failed. It should be passing 6 mA continuous, not enough to damage it and likely not enough to feed the DC-DC and the controller caps.

You're right, kinda. 60mA for 120V/2K, right? But within the 20W rating. So, then there would have been some charge on the controller caps depending on the current the converter was drawing.

pedm should not have wired the converter where he did. But I don't see that as the certain cause for the controller failure.

[Tesseract]

Originally Posted by major

Let's see if the resistor is OC. If it is still 2K, then the converter connection is unlikely the cause of the failure.

From post #1, I suspected another cause

The reason why I'm fairly certain that connecting the dc/dc converter after the precharge resistor killed the controller is because most switchmode power supplies will operate in "hiccup" mode if connected to their supply voltage through the typical value precharge resistor (ie - 0.5k to 2k). The precharge resistor charges up the dc/dc converter's input capacitor, too, and when it hits a certain voltage the PWM chip will turn on and rapidly consume all of the stored charge in the capacitors in both the dc/dc converter and the controller. This cycling repeats until the resistor burns out and/or the main contactor is closed to drive the car.

Did you have another scenario in mind?

Originally Posted by major

I finally figured out how to paste a picture in there

File under: "Old Dogs Learning New Tricks"

[major]

Originally Posted by Tesseract

Did you have another scenario in mind?

Made by Kelly

Originally Posted by pedm

I was thinking about many possibilities to have caused this:
- Because the regen function was activated, and the car was sliding back, pressing the throttle might have shorted something?
<snip>
- I live on the top of a hill, it was taking 120 amps continuously to climb during 3 minutes before arriving home. Turning back on with the controller hot maybe have caused any problem.

Here's a couple. Kelly didn't account for plugging. And/or 120A for 3 minutes is too close for an 800A Kelly controller.

Called me a dog, and an old one. Thanks

[Tesseract]

Originally Posted by major

Made by Kelly

No Comment...

Originally Posted by major

Here's a couple. Kelly didn't account for plugging. And/or 120A for 3 minutes is too close for an 800A Kelly controller.

hmmm... plugging from the car rolling backwards? The tires *should* chirp before the motor generates enough current/torque to cook the diodes inside the controller... "Should" being the operative word here...

Strictly anecdotally, I've heard that the latest Kelly's are much improved in the claimed vs. actual ratings department but, sadly, not much improved in the reliability department. In the spirit of Mythbusters, I'll agree this one is "plausible".

Originally Posted by major

Called me a dog, and an old one. Thanks

The dog part was actually a compliment. In my special little universe, anyway.

[pedm]

Finally kelly replyed to my e-mail :

please don't connect the DC/DC positive on the B+ terminal.
It should be connected to the terminal of power fuse holder.

I measured the precharge resistor, and it is still alive:


They want me to send it back to their factory to double check it, so that we can find out what was the problem.

Before the Fuse I have a circuit breaker.

I usually turned the circuit breaker on before the power switch. And the Power switch off before the circuit breaker off.

You guys are helping me a lot on solving this problem. Thank you!

[pedm]

I received the new controller.

First the car did not reaches 50A ( rated at 300 A constant and 800 peak).

And today I felt a lot of "hiccups" 39A max.

I still can´t move the car to the garage because it is not able to climb the hill. It just stops at the middle punching 39A.

I tested with a filed current of 8A, 15A but the armature current is always the same: 49 or 39A maximum.

I changed to 25% and 50% of motor and battery current. On 50% I started to feel stronger "hiccups".

I disabled the regen, all I want now is the car to work again...

Also the battery terminal bolts are getting small white dots... Seams like a chemical reaction.

The motor is a Kostov 9'' SepEX. Does the problem affected the motor?

[DavidDymaxion]

Pedm: I have the 1000A version of your controller, powering an 11 inch Kostov Sepex. It was painful to watch the video and read about the problem!

• My Kelly will pump current through the field 100% of the time, even when the motor is stopped, foot off the accelerator, or foot on the brake. You should be sure the field current is either low enough to not overheat the fields, or better yet put an electric cooling fan on the motor so it is always getting cooling air.
• It wasn't instrumented well, so I can't vouch for the actual number, but I have run my Kelly and motor at the 1000A setting -- the car was fast enough I believe it could be accurate. I have run the car full out for about 40 seconds, the controller was fine.
• I had heard that Kellys run hot. Mine sits on a huge 11 inch x 17 inch (28 x 43 cm) heat sink, with a huge fan blowing on it. It has always been cool to the touch, I can't detect that the controller heats up at all, so I haven't been using the fan.
• 39 Amps is barely enough to turn the motor in neutral, no surprise you can't get it to drive.
• There is a small chance you cooked something in your motor, particularly if it doesn't have extra cooling -- have you spun up the motor with a 12V battery? Be sure to do both the field and the armature, connect the field first and disconnect it last.
• Get a clamp on current meter and check the field actually has current -- my Kelly always powers the field so you should be able to see this even if the motor isn't turning.
• Why not go to 100% current? You could use your clamp on ammeter to make sure the current stays at a low enough level.
• 39A sounds more like a field current maximum -- just to be sure is that number battery or armature Amps?
• I'd suggest disabling regen until you get the forward motion thing sorted out.

Originally Posted by pedm

I received the new controller.

First the car did not reaches 50A ( rated at 300 A constant and 800 peak).

And today I felt a lot of "hiccups" 39A max.

I still can´t move the car to the garage because it is not able to climb the hill. It just stops at the middle punching 39A.

I tested with a filed current of 8A, 15A but the armature current is always the same: 49 or 39A maximum.

I changed to 25% and 50% of motor and battery current. On 50% I started to feel stronger "hiccups".

I disabled the regen, all I want now is the car to work again...

Also the battery terminal bolts are getting small white dots... Seams like a chemical reaction.

The motor is a Kostov 9'' SepEX. Does the problem affected the motor?

[somanywelps]

Originally Posted by DavidDymaxion

Pedm: I have the 1000A version of your controller, powering an 11 inch Kostov Sepex.

How's that working out?

Voltage and which K11 was it based off of?

[Stiive]

Originally Posted by pedm

It has a precharge resitance. That came with the HSE assembly:

From the looks of the picture, that looks like an AC fuse... Probably not adequately rated to your DC pack, created an arc, and that's why your controller blew and not the fuse.
Also that contactor looks suspiciously like a 96V contactor i have previously used... what is you battery pack voltage? That may not be adequate either.

Is this entire assembly from Kelly? And it just comes exposed like that?