Primary And Secondary Position Feedback - GAL GALaxy eHydro Manual

GALaxy eHydro Elevator Controller
Figure 1-1: Absolute Position System Selector

1.4.2 Primary and Secondary Position Feedback

The Main CPU receives position feedback from the channel A camera CAN bus and builds a table of
floor positions and slowdowns for each floor during setup. On a normal run, the Main CPU uses the
slowdown points to initiate a slowdown to the appropriate floor and uses the floor position to determine
the door zone and exact stopping position.
The NTS processor receives position feedback from the channel B camera CAN bus and builds an
independent table of floor door zone positions and normal terminal slowdown limits (UN, UT, DN, and
DT) during setup. On a normal run, the NTS processor uses the NTS slowdown points to
independently remove power from the appropriate run valves as a redundancy to slowdown and stop
the car at terminal landings.
Both the Main CPU and NTS processor outputs door zone and control signals, (SU, SUF, SD, SDF for
the Main CPU and UN, UT, DN, DT for the NTS processor), to the Safety PAL to make hardware-
controlled decisions that the car is safe to run.
To protect the car from hitting the stop ring at a speed greater than 50 fpm in the up direction, two
mechanical switches are wired in the hoistway at the top terminal landing. The first switch actuated
Section 1 – Product Description
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