LMV Series Technical Instructions
Document No. LV3-1000
SCC Inc. Page 1 Section 5
Section 5: Variable Speed Drive Control
Table of Contents
Introduction ................................................................................................................................ 2
VFD and AC Induction Motor Fundamentals ................................................................................ 2
Line Reactors............................................................................................................................... 3
Output Wiring / Load Reactors .................................................................................................... 4
Shaft Current............................................................................................................................... 5
Braking Resistors ......................................................................................................................... 5
Types of VFDs: Vector and Volt/Hz ............................................................................................. 7
Configuring VFDs for use with the LMV3 ..................................................................................... 7
Brushless DC Blowers (PWM Blowers) ......................................................................................... 9
Centrifugal Blower Fundamentals ............................................................................................. 10
Standardized Speed - Standardizing the LMV3 .......................................................................... 11
Blower Speed Monitoring ......................................................................................................... 16
Blower Speed Response during Operation ................................................................................ 18
Suggested Setup Procedure for the VSD Control - Parallel Positioning Application .................... 20
Suggested Setup Procedure for the VSD Speed Shift ................................................................. 23
Additional Tips for Burners with VSD Speed Shift ...................................................................... 27
Additional Tips for Burners with VSD Control ............................................................................ 28