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 The displayed values are no longer valid.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 The displayed values are no longer valid.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).

Additive Feeders

Chapter 4: Operation

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Sterling AF-XXX specifications Injection Mode Application Notes