How can I improve slow feed rate performance on my HI 2160RC or HI 4060 rate controller?

My HI 2160RC or HI 4060 is feeding at a very slow rate below the recommended feed levels. How can I improve the controller performance to feed at this level?

If you want to improve the slow feed rate performance on your Rate Controller you need to remember that the backbone of a rate controller is the rate of change calculation. The goal is to allow the rate controller to calculate a consistent rate of change and produce smooth and equal control.

Rate of change is a product of weight change over a given time base. The typical problem is a bad calibration, bad or oversized load cell, poor scale installation, the material does not flow consistently, or the amount of flow is below the resolution of the scale system. Before any control can be achieved the scale system must return a clean rate of change signal. There are several items under the configuration menus that can be adjusted to improve how the scale information is processed.

IMPORTANT: When a feeder system does not operate properly, do not over look scale mechanics (including binding and bridging material), environmental and electrical noise conditions. A scale problem can result in poor feed rate control. Remove any cable binding or rubs, and connect the mounting cabinets and junction boxes to earth ground. Verify cable routing, grounding, and the shields terminate to a single point and at the power source end of the cable. There are additional tips in the troubleshooting section in the rate controller operation and installation manual and in the Hardy's Webtech online knowledebase. (search "lockup" as a key word.)

We suggest you use Hardy Process Solutions C2® certified cable if multiple load cells or remote controller locations are used. If a single load cell is used in an application layout, the single load cell lead could terminate directly to the controller.
Using a portable scale and catch container can help set the rate cal numbers. This could prove to be an unreliable method if the catch method is flawed. Blow-by information from the catch container or transfer errors to the scale could induce errors. This will cause an error in establishing the rate cal numbers. If caution is taken the catch samples will reflect the true rate of change.

On applications where you cannot catch the material and it has to be run through the process.  You can run live and collect the rate calibration information on the fly. 

On the HI 4060, HI 1769FC, and HI 1756FC you can use the OP%, ROC and ACT readings to reflect the actual rate.  This assumes the calibration is correct.  The ability to read the ROC in the manual mode allows you to tune on the run.  Select a rate just under your target rate and then adjust the manual OP% until the lower target rate is achieved. Repeat the run with a target slightly higher than your normal target setpoint.  Using these two point you can enter a rate calibration using ADVANCE Mode in the HI 4060 and User set cal in the HI 1769FC and HI 1756FC.  Input the two rate percentages and OP% and then do the mentioned rate calibration.  In Advanced or user set mode the feeder will not activate, only calculate the rates across the board.

Optimize the ACT and OP% motor output by setting the PID numbers. Auto rate calibration sets these values to a balanced output. The PI are the product of Averages, Time Base, and Rate Of Change. Where the OP% controls the feeder speed and ACT (actual) displays the averaged flow rate over a specified time base.

The HI 4060 PI numbers are actual PID calculable numbers and can be changed/tuned on the fly. The P is the percentage of change for each correction, aggressiveness.  For middle of the road update rates, use the P number set during the rate calibration, or increase.  For a slower correction reduce the P factor.  The I is the speed at which it obtains the target over time.  Increasing from the rate cal setting will cause overshooting.  Reduci