CONTREX ML-Drive - Manual (Page 47)

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Follower Mode
The Follower mode of operation is the most frequently used mode of operation. It is a
multi-motor operation in which the entire process can be controlled by any number of
motors and ML-Drives.
The ML-Drive allows you to control your system in Follower Engineering Units
(e.g., Follower to Lead ratio or percentage of RPMs, gallons per minute, feet per
minute). The Follower Engineering Units that you want the system to operate at are
entered into the two available Follower Setpoints (CP-03 and CP-04). However, before
the ML-Drive can determine how to operate at these setpoints, you must enter Scaling
Control Parameters into the ML-Drive. Scaling is a convenient method for translating
the relationship of the Lead and Follower motor RPMs into Follower Engineering Units.
Scaling Control Parameters give the ML-Drive the following information:
Max RPM Lead (CP-33)
Measured at the Lead sensor shaft, this number is the maximum RPMs
at which the Lead will operate in your system.
Max RPM Feedback (CP-34)
Measured at the sensor shaft, this number is the maximum RPMs at
which you want the follower to operate when the Lead is operating at its
maximum RPMs.
PPR Lead (CP-30)
The number of gear teeth or number of encoder lines on the Lead
sensor per revolution (pulses per revolution).
PPR Feedback (CP-31)
The number of gear teeth or number of encoder lines on the Follower
feedback sensor per revolution.
Follower Engineering Units (CP-21)
Enter a number that will represent the setpoint Engineering Units when
the Lead and Follower are operating at their maximum RPMs. This
number is usually either the ratio of Max RPM Feedback (CP-34) to
Max RPM Lead (CP-33) or the ratio of Follower to Lead Engineering
Units at maximum desired RPM. When this number is also entered as
a setpoint (CP-03 or CP-04), the Follower will operate at maximum
desired RPM when the Lead is at maximum desired RPM.
The factory default Control Parameters for Scaling are found on Table 3-8. To modify
these default parameters, refer to Table 3-9. If you are uncertain how to enter a Control
Parameter, review the
Operations: Keypad section, page 3-3.