Synchronizing controller
80
MG.10.N4.02 - VLT is a registered Danfoss trademark
Glossary of key terms
Master-Slave
- It means that a signal is taken from a master drive. The signal is then used to
control a second, “slave“ drive that follows the master. The master drive does
not have to be a drive; it can be any given part of a power transmission
system.
Incremental encoder
- This is an encoder system that picks up the speed and the direction
of rotation and transmits on the appropriate configuration. The number of
tracks, and thus the number of signals, indicates the properties of the
encoder system. There are single-track systems that deliver a pulse signal
dependent on the speed as well as a fixed direction signal. Dual-track
systems deliver two pulse signals that are offset 90 degrees. By evaluating
the two tracks, the direction signal is also obtained. Three-track encoders
deliver, as well as the two tracks of the dual-track encoder, an additional
“zero-track“. This emits a signal when the zero transit is passed through.
Figure 27: Incremental encoder signals
Quadcounts
- Through edge detection, a quadrupling of the increments is produced by both
tracks (A/B) of the incremental encoder. This improves the resolution.
Figure 28: Derivation of quad counts