I wonder if you could have a drive offset problem. I am just basing this off of general drive principals but the car has to be able to hold zero speed long enough for the brake to set. Is there a way you can put a scope on a current feedback circuit and verify you are not getting a spike in current as the car stops due to noise induced by a poorly suppressed relay coil collapsing?
good point, I was waiting for a chance to offer the same question but have been busy.
does the motor still have voltage on it AFTER the brake is set? are you pulling through the brake with stored energy in the motor? could it be stored energy?
have you compared settings to the unit you say is running fine?
have you brought the weights over and verified the brake is set to hold 125% of full load?
First of all, on a good car, you can watch the main contactor and brake leds, on the HCB board. When both the leds are lit, that means the drive is on, (201 picked), and the main brake coil is picked.
When a good car comes to a stop, you can see a very obvious delay, where on the HCB, the main brake led goes dark first, and then the main contactor led stays up for just a little bit, before also going dark.
On the bad car, the leds on the drive HCB board are doing EXACTLY what they are doing on a good running car. It is the intention of the drive to keep the motor torque up for a bit, while the main brake sets.
That's it's intention....good intentions...
But that's not what is happening with the output of the main brake power supply, and the 201 main contactor.
What the bad car is doing is this-
The main brake pick command, (24vdc, referenced to ground), is fed from the drive HCB board, to xb2-7 pin on the main brake power supply.
On a good car, when this main brake pick command goes low, the output of the main brk ps drops out immediately. No command, no output.
But on our bad car, when the main brk pick command drops to 0 volts, the output DOES NOT TURN OFF right away. It takes a few milliseconds for the output to turn off.
So the drive has the intention of dropping the main brake first, before removing the motor torque,
BUT-
The main brake power supply is schizophrenic, and marching to the beat of it's own drum. Our brake voltage decays simultaneously, with the drop of 201, and removal of motor torque. This must not be, because we need the brake to set before the removal of motor torque. Otherwise, it will roll-up before the brake sets. Which is what this car is doing. No no, can't have it this way. MUST drop brake voltage first, before the drive shuts off.
There is a pot inside the main brk ps, located on a timing relay (416), but it's only purpose is "economizing", or reducing the brake voltage during a run. THink of it as a cooling resistor! Tried turning the pot anyway, had no efffect at all.
Tomorrow, gonna take the main brake power supply out, and swap in a good one, see what happens.
Kone wants WAY too much money for the boards. An ADON board costs thousands, door operator board looks like it's worth $250, they want $2,900 for it, a motor tach is in the thousands, etc, etc. Spare parts cost way too much.
I don't appreciate the fact that the event log has no date and time stamp. You can't tell easily where one fault starts, and the other one ends, or when it was running on auto between faults, or for how long, what floor a fault occured on, etc. It does show the state of all basic signals, when the fault occured.
The 77S, 77N, 77U rail magnets are just stuck on the rail, without a bracket, w/o some recess to fit into, not even a spray paint shadowing. Seems like an afterthought, poorly executed.
The control program seems too uptight, too highly strung. It shuts down if a leaf falls on the roof, spits out codes left and right. Kinda flakey.
Removing the HCB board in the drive is a root canal. I've never worked on any controller that had a board so difficult to work on.
Compare the above to an MCE 4000 traction control, well, you can't, cuz there's no comparison. According to an engineer from MCE, a local Kone office asked MCE to design a mod controller, to replace the KCM831 and V3F25. They were gonna do so, but word was Kone hdqrtrs in Finland put a stop to it. I can see why, it would have been a black-eye for Kone if one of their own offices contracted with MCE to replace their own stuff. But this stuff is a black eye on them anyway...so it's a moot point. Maybe they were afraid contingency attys would smell blood in the water.
Short answer? Get a Motion controller.
Now that you've dug into this control and motor, more than any other NON-OEM that I've heard of...
What is your opinion of this control????
Must be a tough go for an independent.
The main brake pick command from the HCB drive board to the main brake power supply wasn't turning off all the way, just going sorta "brown". On a good car, it drops to 0, but with this bad drive board, the pick command voltage wouldn't drop off to absolutely zero, rather, it hovered at about 18 volts. It was low enough for the main brake power supply to "eventually" turn off, but it wasn't shutting off it's output quick enough. Which is why the main brake was staying picked for just a few milliseconds too long, allowing the roll-up, and subsequent releveling failure.
The pick/drop command really just "browned-out", rather than going all the way to 0 quickly. This adversely affected the timing of the brake release.
When you are troubleshooting, we tend to think of things as basically working, or not working. One might assume the "pick/drop" command was fine, since the brake was indeed "picking", and "dropping"! Many of us turned our thoughts to other possibilities. But it was the quality and characteristic of this signal that caused the problem. The scope helps to see signal timing relationships and voltages very plainly, which is why I trot it out, when something weird is kicking my butt.
The shorted motor (original problem) put a ton of stress on the drive. I don't know if you read my thread on that issue, but it was turning on and shutting off with rapid, high-current pulses. It was alternately turning on and shutting off on max current limit, protecting itself. Only this happned very rapidly, like a jackhammer. The drive was not designed to endure such a high-current, high-heat duty cycle, not to mention the current spikes and emf it caused. Punish a drive that way for a while, and it will have some kind of failure. Abnormal conditions would definitely include a shorted motor!
It actually ran for hours and hours before a troublecall was originally placed. This heated up the motor, heated up the drive cabinet, and took out the HCB board. That is beyond is design parameters. Before the motor issue, there was not a releveling problem on this car. Only after the motor issue was resolved, and the car turned on for the first time, was the issue with the HCB revealed. We couldn't check for that, nor evaluate the drive in any way, without a good pmsm motor to drive. So this is how latent issues are progressively revealed, after a major issue like a shorted motor has occured.
Semper Fi
I've follow your posts from the beginning. As trying as it appeared to be thank you for your posts.
It was a great ride!
Jon
I've follow your posts from the beginning. As trying as it appeared to be thank you for your posts.
It was a great ride!
Jon
As difficult as some problems are, they still intrigue me. It's kinda like a fox hunt. Sometimes I get 'em, and sometimes they beat me up! But we've never just "called it quits", that's not an option.
I'm glad this was of some value. I sure learned a lot from everybody here.
Good job on the fix and the documentation of the process!!!!!
Agreed.
Sometimes we dump on them unfairly. But I still fault them for no time/date
stamp, and way expensive parts!
Thanks for your input, and following along!
Good job on the fix and the documentation of the process!!!!!
Good job on the fix and the documentation of the process!!!!!
Glad it was interesting. Kind of like a mystery novel? 8^)