Oops!
My Concord Series 8000 Pro Lift Elevator was failing to decelerate during descent.
Troubleshooting indicated a fault in the 772048 (mod 772041) proportional control valve.
A 470 mf radial electrolytic capacitor was swapped with Mouser # 647UPW1H471MHD, Mfr. #: UPW1H471MHD Aluminum Electrolytic Capacitor Radial 50volts 470uF AECQ200
A Sipex 805LCP integrated circuit was swapped with Mouser # 700MAX805LCPA Mfr. #: MAX805LCPA+ Microprocessor Supervisory Circuit
A CSI 93C57P integrated circuit was swapped with Mouser # 57993AA56/P Mfr. #: 93AA56/P EEPROM 256x8128x16 1.8V
The elevator now decelerates on descent, and operates normally … however …
The control board no longer stores modifications to function parameters.
It loads factory defaults.
According to documentation, the values are correct for initial installation.
I can live with it for the time being.
But I’d like to fix it the right way.
Who can tell me what happened? I’m guessing one or both IC is not an exact replacement.
