Had a new customer come to us for service on his residential elevator (3 stop) - he said a previous elevator company serviced it, there was an issue with the bottom door lock they told him and he has not heard from them since and hasn't been able to get in touch either. We went on site and found the bottom door lock keeper was removed from the door and simply stuck in the lock so that the door could be opened, obviously a huge safety issue as this also means the elevator could run with this door open and you can open this door at any point... so we reinstalled the keeper to the door. The doors have Porta Locks and it seems the issue is with that bottom lock not unlocking when the lift gets to the floor. We replaced the lock, thinking the solenoid or some contact inside was bad but still have the same issue. We basically traced the problem to the controller - we swapped wires going to the first floor lock and moved them to the terminals for the middle floor, sent the car and the lock worked properly which tells me it's something in the controller not sending the proper signal to the door lock. further troubleshooting found a small diode that is connected to each door lock circuit.... we basically swapped the diode for the bottom floor with one from the top floor (as the top floor lock worked fine) and tried it but still nothing - we actually found it burnt out that diode we swapped as we installed it back into the top floor circuit and the top floor lock would no longer operate properly - luckily we had a spare on site to replace that.
so currently we have the lift running only to the top floor and middle floor, the bottom floor door is locked but still does not open. We know the bottom floor door lock is good and the field wiring to the lock is good....we have a set of diodes to replace the burnt out one for the bottom lock however we are assuming this will not resolve the issue as it seems to be elsewhere in the controller that is causing the problem. Wondering if anyone has any recommendations, info, etc so we can hopefully resolve this issue when we return.
