User Manual

Rockwell Automation Publication 20P-UM001K-EN-P - July 2014 283
Application Notes Appendix C
Example 5: Encoder with Field Weakening
This example is similar to example 4 except that an encoder is configured so there
is no feedback scaling required.
• Par 175 [Rated Motor Volt] = 500V (default)
• Set Par 45 [Max Ref Speed] = 2500 rpm
• Set Par 162 [Max Feedback Spd] = 2500 rpm
• Set Par 169 [Encoder PPR] = 240 ppr
• Set Par 585 [Overspeed Val] = 2750 rpm
• The reference and feedback resolution = (7500 fpm/25000 counts) = 0.3
fpm/count
Speed Feedback
Regardless of the type of speed feedback device used, (selected in Par 414 [Fdbk
Device Type]), the value of parameters 162 [Max Feedback Spd] and 169
[Encoder PPR] must be in the allowed area shown in Figure 85
on page 284
based on the value of Par 175 [Rated Motor Volt].