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, setting _RP to 00000 will prevent any shortage from occurring. This will, however, cause an overall average error on the plus side.
NOTE: Remember that EITHER ONE of the these two parameters will cause retries to occur. BOTH parameter conditions must be met before the process will continue, with one exception: If the ALARM parameter (_AL) is set to 00000, indicated that you do not want any retries to occur, then these two RETRY parameters will have no effect. The first dispense will always be accepted and no retries will be made.
The _RD parameter is adjusted automatically by the software after every power on, after the blender has been operating smoothly, without retries, for 10 cycles. If you wish to change _RD and have it stay changed, then enter a 1 as the first digit in the parameter:
(_RD 10020). The 1 signals the software to NOT make any automatic adjustments to this parameter.
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_LA (change if you change metering device)
_LA is the lag TIME before dumping actually starts. This lag time is the time it takes for the dispense system to mechanically respond to the controller's signal to start. Lag time is automatically added to all dispense times.
Changing the means by which a device is operated such as using a different diameter air cylinder, or a different drive system for an auger feeder may require a change in this parameter.
These parameters represent the number of interrupts (time) that pass before the feeder or dispense system actually begins to dispense. There are 244 interrupts per second. To determine these times, use the TIME dispense function in the Manual mode (KEYPAD instructions).
Following the instructions given in the KEYPAD portion of the manual (TIME key), start with a dispense time of 1 (001). Try successively higher time numbers until some movement is noted in the mechanical device and a minimum amount of material IS dispensed on each try. This is the MINIMUM lag time number; the lowest number that DOES cause some movement and DOES result in a minimum dispense. Add 5 to this time period and use this number as the lag time. Lag times that are too short can cause problems. That is why the MINIMUM lag time determined above should be increased by 5 as a safety factor.
Use minimum plus 5.
These numbers are preset at the factory for the equipment we have supplied. When a dispense of only a few grams or a fraction of a gram
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