Symptoms from inside the car:
Running normally, come to a floor, door opens, door closes. Immediately the annunciator reports "We are experiencing technical difficulties." All car calls drop. After between 5-15 seconds, the car will once again take car calls and all is well. The elevator can go for a day, or sometimes the symptom occurs after 10-20 runs.
The problem occurs in both up and down directions. It also occurs after I've taken the car out of the group and turned off door operation.
Symptoms from the machine room:
Everything is running normally, and then all of a sudden in will go to NAV. After a few seconds, it will go back to NOR. The MCSS faults show a 2700 and a 2702. However, the brake is not the cause, but that's the first thing the computer picks up. Those are the ONLY two faults, and they occur EVERY time this event happens. What I DON'T get is a U or a D. They turn on through the MCB board, but I don't know what happens prior to that, to turn on the XU and XD signals. I can see that they're turned on by modules on the board, but that's it.
What I've tried:
I've replaced the MCB with one from Otis. I've replaced all the relays that turn on with the self check (CIO?). And today I replaced the Ring Board.
Any ideas what direction I can take this on Monday morning? I can go 150 runs with everything ok, and then all of a sudden I'll fail to get the XU or XD from the MCB. I'm stumped.
Thanks.
You say "it's not the brake", although both your faults point to it. I don't know what faults 2700 and 2702 are exactly (obviously brake related), but let me ask, is there a brake switch on the brake itself? If so, have you metered the contacts opened and closed? Sluggish to drop the switch contact after a run can generate faults.
Or if no switch is present, have you checked the brake relay itself?
I don't know how to do that.
Do you have a procedure or address?
If nothing else, if the car doesn't shut down for the brake fault, it might give me more time to watch and see what's happening.
Thx.
Brk sw pres
Change to 0
Jump out brake switches in controller .
You should only do this as long as it takes to prove the switches are or are not the fault tho . If they are then Otis sell a replacement kit .
The problem might be resolved. Once again, this morning I went over all the basic things and found nothing of consequence. So I set up to watch the drive's LVIB (specifically the U30, UDX, and the UDX LED).
200 runs later, there were no anomalies, so I turned the car loose. It's at 306 uneventful runs as I type this.
I didn't disable brake monitoring, as I didn't figure out the secret key codes until just now.
Gonna watch it some more.
Nah, I dig a challenge... as long as I don't let the pressure get to me. That is the REAL challenge. This one went on too long. Hopefully tomorrow's new challenge will be easier.