Sterling AF-XXX Manual Do Utilizador

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Additive Feeders 
Chapter 4: Operation 
27 of 55 
feeder. If you do not have these drawings contact service to have them forwarded to 
you.  
 
Injection Mode Application Notes  
 
The additive feeder controller has the ability to display feed rates in units other than the 
factory set auger RPM display.  With proper programming, the feeder can display 
pounds/hour, grams/minute, etc. 
 
Programming for units other than auger RPM REQUIRES that the system be calibrated to 
determine exactly how much material is delivered at specific RPMs.  Please refer to the 
Calibration Procedure section for additional details. 
 
Please note that custom programming for units other RPM will only provide meaningful 
results when the auger and sleeve size does not change, and when the materials to be fed have 
similar physical characteristics.   
 
Example 1:  The unit is programmed by the end user to display feed rates in pounds/hour 
with a ¾” auger and sleeve.  Someone else replaces this auger and sleeve with a 1” diameter 
unit and does not calibrate and reprogram the controller.  The displayed values are no longer 
valid. 
 
Example 2:  The unit is programmed by the end user to display feed rates in pounds/hour of 
a pelletized colorant material.  The pellets are of a uniform size and shape, freely flow, and 
contain no extraneous materials.  At some point the additive feeder is used to introduce 
regrind material instead of the previous colorant pellets and does not calibrate and reprogram 
the controller.  The displayed values are no longer valid. 
 
When the controller is to be programmed to display in units other than auger RPM, 
parameters P20, P21, and P30 will need to be modified. 
 
The value in parameter P20 must be programmed to the lowest desired delivery rate.  The 
value in parameter P21 must be programmed to the highest desired delivery rate, and the 
value in parameter P30 must be programmed to a value that matches what the auger delivers 
when it is operating at full speed (71 RPM). 
 
Example 1:  An end user wants the additive feeder to display how many ounces per second 
are delivered rather than what speed the auger is to turn at.  When the end user calibrated the 
unit they determined that at 10 RPM the unit delivered 1 ounce per second, and at 71 RPM 
the unit delivered 7.1 ounces per second.  The end user wants to be able to set the control to 
deliver between 2 and 5 ounces per second.  The value in parameter P20 gets programmed to 
“20” which will allow a minimum setpoint of 2.0.  The value in parameter P21 gets 
programmed to “50” which will allow a maximum setpoint of 5.0.  The value in parameter 
P31 gets programmed to “71” which is how much material is delivered when the unit is 
rotating at full speed (71 RPM).