16
HYDROFIT
™
Owner’s Information Manual
WARNING: The use and ownership of this work is defined in the legend upon the front page hereof.
The Microprocessor Controller
The controller is the central nervous system of the elevator. The controller assembly
houses electrical, electronic, and microprocessor components that provide three main
areas of control: motion, operation, and door control. It is here that all signals are
processed. The signals are either generated by a passenger, such as calling the car to a
landing, or the system itself, such as monitoring systems to ensure they are operational.
The hydraulic control board coordinates all of these signals. If you think of the controller
as the central nervous system, then the hydraulic control board is the brain. The board
includes two printed circuit boards:
• The Microprocessor Board
• The Input/Output Board
Today, we find the microprocessor in many applications used in our everyday lives:
appliances, automobiles, banks, and so on. It is also used extensively in elevator
control. Although small, it contains thousands of integrated circuits on a single
chip. Prior to the microprocessor, elevators used discrete parts such as resistors,
capacitors, and switches to do the same work. However, very large enclosures were
required to house these parts.
The primary functions of the controller are to track the direction and position of
the elevator car, monitor the safety circuits, and respond to the elevator’s demand
patterns efficiently. The system and passenger information (in the form of electrical
signals) are directed to the input/output board. One of the functions of the input/output
board is to serve as traffic manager of the signals to and from the controller.
The controller needs additional instructions, or inputs, to make a correct decision.
The instructions for the controller are kept in programmable chips on the microprocessor
board.
The controller takes the system signals, which represent various conditions within
the elevator, and processes or samples them against the programmed instructions
maintained in the memory chips. Based on the processing of the data, the controller
makes new instructions.
Instructions, in the form of signals, are sent to various pieces of equipment to carry
out operations properly, within acceptable time, and in a safe manner. The
microprocessor has the ability to change instructions easily. This may include adding
features to your elevator service. Changing the program instructions is all that is
required to accomplish this; additional components or wiring are not needed. Information
in the microprocessor is used to help troubleshoot the elevator. There are
three basic methods to access this information:
• Otis Field Tools (OFT)
• Remote Elevator Monitoring (REM®)
• Light Emitting Diodes (LEDs)
