Porter 91101-100, Инструкция по установке, эксплуатации и обслуживанию

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Page 22
FIGURE P
17. HOW THE SELF-LEVELING/MONITORING SYSTEM WORKS
The control panel is furnished pre-wired, programmed and factory tested to provide
proper operation. Each hoist has a built-in reed device (see
Figure P ), which ensures
the motion of each hoist is transmitted to the control system a minimum of eight (8)
times per 12” of travel. If one of the winches is not operating, or the reed device is
disabled (loose wire, etc.), the watchdog timers will be timed out, disengaging the
system for approximately 60 seconds. If the key switch is actuated before the 60
second time limit, a new 60 second “time-out” clock will be started. The system must
be inspected to determine the cause of the one unit not running, or the reed device
being by-passed, before the watchdog timers allow the system to run consistently.
The reed device also ensures the load bar stays within approximately 3” of level during
the operation cycle. If one unit operates (winds) faster, the unit will
automatically shut
off. The operator simply needs to turn the key to “OFF,” and then turn the key back in
the corresponding direction the hoist was moving. If the alignment adjustment is signif-
icant, one unit will raise (or lower) itself and shut off again. Turn the key to “OFF,” and
back to “ON.” Both units will now raise consistently. If the alignment problem was not
significant, the “OFF/ON” scenario will only be required once by the operator.
The load bar will level and reset the counter on every down cycle. It is important that
the operator hold the key in the “DOWN” position until both lower limit switches are ac-
tuated. This will zero out the internal counter and reset the unit.
If the lower limit
switches are not adjusted properly, the load bar will stay misaligned. See Step
15 for setting the lower limit switch.