or you can email me and i'll give you his phone number... ifrratedpilot@msn.com

Thank you, ifrratedpilot

jkh, I'll remember to check the limit. Good thinking

theshaft, we got both brakes at a tight .003", but will drop down to.002"

Thanks very much for the offer. I might take you up on that.

Tomorrow we've got a lot of things to check, we'll see how it goes.

It sounds like your service brake is not holding the car. This brake alone should hold it in place and the e brake is a back up. If you have an extra brake change it or lock the car on the pins and swap out the ebrake for the service brake. It sounds like its hanging up and not setting properly. I came across this problem over a dozen times and changing the brake fixed it.

Thanks for the idea

We could swap the brake coil + switch wires, too

If the problem goes away, we'll know one brake has an issue.

But I don't think the main brake is slipping at all. The car actually
stops very abruptly when the coil is de-energized.

It's just that it rolls up, before the shoes contact the drum.

Hey brake needs to be set at .002. Use a brake tool. If u don't the brake will sag a little on inspection. Also it sounds like your brake is not centered in the hole. This will still allow it to pick but will cause it to drop at a angle of the drum. Also if u have the KDL drive on it and the car drifts up only on the top floor, after it parks I have a fix for that. But PM me if that's the case.

Its not a KDL...but if it was, the fix for the problem you describe is...6_12_0 right?

If your unit has the machine tach in addition to the resolver - check for slippage.

itsallgood, thanks for the suggestion. Will do.

So far, we have done the following-

Completely reset and calibrated loadweighing.
Set resolver angle.
Verified tach polarity, and resolver polarity.
Checked tach voltage, and adjusted tacho pot.
Dumped the drive parameters, and reloaded them.
Shaft learn.
Adon learn.
Adjusted both brakes to about .002".
Adjusted brake switches.
Tried swapping brakes.
Checked dead zone.
Checked limits, just for good measure.
Cleaned brake drum at great length, but could use even more. Odd.
Tried running it up at high speed twice, then dropping the brake, to burnish it, burn off any contaminants.

Today, I checked the brake really up close and personal, and found that when you're on car top inspection, going up, and you release the buttons, the main brake sets right away, but the rotor moves like an inch or an inch and a half, before stopping. At the suggestion of a friend, I cleaned the brake drum with denatured alcohol, and man was it dirty. The dirt just kept coming off, and coming off. I wondered when a clean rag would come out clean, but it never did. So I quit cleaning the drum for a bit, and looked at the shoes, to see if they were oil soaked, and maybe that was leeching crap back onto the drum. But the shoes looked typical, just like the other good running cars.

If I put 2000# in the car, it comes into floors perfectly, and stops perfectly, and does not relevel at all.

But with an empty car, the current state of affairs is that it comes into any floor perfectly, (up or down), levels in perfectly, comes to a complete stop as it should, (61U and 61N are high at this point), but then as the main brake sets, the car drifts up like 1/2, then it is out of the dead zone, so it wants to relevel downward. Which it does. Yes, indeed, it relevels perfectly, comes to a complete stop for the second time, perfectly level, but then again, as the main brake sets, the car again rolls up and out of the dead zone. It kinda makes you wanna reduce the main brake to .0005" gap! The fact that it comes in so controlled, so smooth, dials itself into floor level so very finely, and comes to a complete, dead stop, exactly at floor level, each and every time, tells me that this issue isn't a dynamic issue related to the S-curve, dynamic braking, loadweighing (with one small caveat), limit switches, resolver angle, tach, etc, etc. All those things will affect the way the car runs, and may affect the way it stops, sure. But this car we're dealing with here, runs perfectly, slows down perfectly, levels perfectly, stops perfectly, perfectly level with the floor, each and every time, any direction, all floors-

Then it rolls up out of the dead zone, while the main brake sets!
This issue appears to have nothing to do with any dynamic forces/adjustments during the run. It runs perfectly. Just doesn't "stay put" while the main brake sets!

I did notice that a V3F18 drive haas a brake timer parameter, 6-43, but the V3F25 doesn't have this. I was really hoping there would be a parameter that would hold torque on the motor for a few milliseconds, until the main brake is well and truly set. But there isn't such a parameter, or at least it's not field adjustable. I was really wondering what the timing relationship was, between the drive shutting off, (no motor torque), and the de-energizing of the main brake.

I wanted to investigate the timing relationship between the motor torque, and the operation of the main brake, to see maybe if our "bad" car has too much time between the cessation of torque, and the de-energizing of the brake. So I took my trusty oscilloscope, (BK PRecision, $200 Korean special build), and went over to a good running car. I hung one probe on the main 201 contactor coil, and the other probe on the main brake coil. First off, the brake is only half wave rectified DC, and not even filtered, which sounds pretty rudimentary these days...but onward-

Watching the dual traces, it was clear, that the main contactor stays energized for like a half a second, after the main brake coil de-energizes. Well, of course. How else are you going to fight gravity from pulling the cwt downward, which pulls the car upward, until the brake has set? I knew there had to be a delay, where the motor torque holds the car, while the brake completes the mechanical motion of setting. Yes, the gap is very tight on these brakes, but it is not "0". The drive and the main brake do not de-energize simultaneously, no, rather the motor stays up for a bit, giving the main brake a few milliseconds to set.

Tomorrow, I check the "bad" car. If the timing is identical, then it's back to the brake. Full disassembly, check shoes wear pattern, look for soaked/contaminated brake shoe material, cleaning, lubrication where appropriate, and re-adjustment. Maybe scuff the shoe surface with some emery cloth.

Vic...
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????

Is there a way for you to verify the drive can regulate zero speed?
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?

Smitty...

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?

Uhm, great ideas all, but maybe best to just tell you what I've found out today.

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.

Uh, well, at least I am able to trace signals through the controller, so that's not too bad.

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.

That's kind of been my impression as well. Wonder if Kone's even making any $$$$ on this stuff???

Must be a tough go for an independent.

Today, she's fixed.

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.

I'd like to thank everyone for their extremely valuable input, especially Elevator Steve, and all the suggestions taught us a lot, and ruled out a lot of things, and gave me confidence to carry on. You guys are the wind in my sails!

Semper Fi

Vic
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

what you said is an amazing analogy of many problems that I find. The hanging voltage or the voltage that hangs in the middle that causes false firing and slow relay picking is so common among what we do. I can't even begin to tell you, how many arguements I have had in the last 20 years, with design engineers over this type of failure that I have had. I can honestly say that in the last year alone I have replaced at least twenty boards or more with this problem, from many different controllers. Every one I send back they just say it was a bad chip. I really wish we could get the engineers of the company's that we all work for on this forum. What a great help it would be for them and us, with the instant feedback that would be provided to them.To bad proprietary interests bind their every thought and action.

PS, thank you to all you guys on here that give all they got:>