Trend ColumnsThere is a vertical column of colored lights
for each slide corner. By just glancing at these lighted columns you can
immediately tell how a job is running.
The TREND columns are calibrated so each light represents a specific
percentage of deviation in tonnage (load). For example, if the
instrument was monitoring a tolerance bandwidth of plus (minus 20%, each
TREND light would represent a 5% deviation from the optimum tonnage.
- The center green GOOD lights of each column will be the only ones
lit when the press is forming parts at the optimum tonnage.
- One of the red HIGH ALARM lights will turn on if the tonnage
exceeds the high tolerance limit you selected for that corner of the
slide.
- One of the red LOW ALARM lights will turn on if the tonnage does
not reach the minimum tolerance level you selected for that corner of
the slide.
- Any green or amber lights that are lit between the GOOD light and
an ALARM light show you that the forming process is not optimum but is
still safe. If any amber light is on, the forming process is getting
marginal. You should think about stopping the press to look for
potential problems.
Any time a red light turns on it means an off-tolerance or overload
condition occurred. The press will be stopped. The red ALARM lights are
tied to factory calibrated TOLERANCE band selectors inside the
instrument. This gives each red HIGH or LOW alarm light a specific
percentage value.
Alarm Levels
Eight alarms monitor for an overload on any corner of either slide
and are manually adjusted when the instrument is installed. The
additional TREND alarms are for die and product protection. There is one
HIGH alarm and one LOW alarm for each slide corner. They are tripped by
excess deviation in tonnage. These TREND alarms will be adjusted
automatically whenever the instrument is put into a MONITOR PARTS mode.
The trip points of these TREND alarms are established by the TOLERANCE
control selectors. No operator interaction is required to set these
TREND alarms once a satisfactory tolerance band has been established.
Tolerance Selectors
There are two 10-position TOLERANCE switches for each corner of both
slides. The setting of these switches determines the tolerance band to
5% then any tonnage deviation in excess of plus/minus 5% would trip an
alarm and stop the press. All TOLERANCE switches may be set to the same
number. Or, each switch may be set to a different number to custom
tailor the tolerance band for complex forming operation. It is generally
not necessary to alter the tolerance band or change the switches every
time a new job is set up.
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