Maguire Products WEIGH SCALE BLENDER WSBMB Series, Установка, эксплуатация и обслуживание

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M A G U I R E P R O D U C T S , I N C .
88
W E I G H S C A L E B L E N D E R
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_PT For augers and micro pulse devices only
The _PT parameters will cause the first try dispense to be a percentage of the full
target weight. For example, with component 4 set to (4PT 00090), the first try will be
90 percent of the full target amount. Retries then occur, but each will target only 50
percent of the remaining requirement. A series of progressively shorter retries should
be expected, until the retry parameters are satisfied (RP and RD). The _PT
parameter is most effective for slow dispense devices, like augers. When setting
_PT, also set the _RP parameter to 00001. This forces retries up to within 1 percent
of target, instead of 10, improving accuracy.
_RP
_RD
No change required
_RD is set AUTOMATICALLY by the CALIBRATE routine
These two parameters determine the dispense shortage error that is be acceptable
for each component.
_RP is the shortage expressed as a PERCENT of the target dispense weight and
_RD is the shortage expressed in GRAMS. These parameters are used together,
either one will force a "retry".
A "retry" is an additional dispense that is calculated to add the amount of material
that is short. This comes into play only when the amount dispensed is less than
expected. Retries will occur until the difference between the required amount and the
metered amount is equal to or less than the _RP percent difference AND the _RD
weight difference. These numbers dictate just how close to perfect the dispense has
to be before going on. If the dispense overshoots the target, then the process
continues. These parameters only control the degree of weight SHORTAGE that is
acceptable.
The _RP parameter is important when SMALL DISPENSE requests for color or
additive are made. Large PERCENT errors are more likely to occur when very small
dispenses are requested.
The _RD parameter is important when LARGE DISPENSE requests for color or
additive are made. Large GRAM weight errors are more likely to occur when very
large dispense percentages are being requested.
Depending on the accuracy of the metering device, a certain amount of hunting is to
be expected from one dispense to the next. Allowing the software to stop trying
when it gets sufficiently close to the target results in more perfect average dispenses.
The mix chamber and the barrel of your process machine average out the small
errors that occur from cycle to cycle. If no shortage is ever to be allowed then these
parameters can be set to prevent any shortage from occurring. This will, however,
cause an overall error on the plus side.