8
SM-Encoder Plus User Guide
www.controltechniques.com
Issue Number: 3
3.3
Set-up parameters
All parameters associated to the SM-Encoder Plus can be found in either menu 15, 16,
or 17. Each of menus 15, 16, and 17 refer to one of the available slots into which the
SM-Encoder Plus can be fitted. Slot 1 = Menu 15, Slot 2 = Menu 16, Slot 3 = Menu 17.
3.4
Compatible with encoder types
The SM-Encoder Plus will allow for the following encoders to be used with Unidrive SP:
Incremental encoders Ab, Fd, and Fr
This type of encoder gives incremental position and can only be used for control in
Closed Loop Vector and not Servo mode.
Ab, Fd, Fr
Quadrature detection logic determines rotation from the phase relationship of the two
channels. These encoders are available with a marker pulse, which identifies each
individual rotation of the disc, and is also used to reset the drive position parameter. The
incremental encoder can be used when operating in Closed Loop Vector mode, with the
optional marker pulse not being required for correct operation.
*
Max input frequency = LPR x rpm / 60
Type
Encoder
Description
Pr x.15
Incremental
Ab
Quadrature incremental encoder.
With or without marker pulse.
0
Fd
Incremental encoder with frequency and direction outputs.
With or without marker pulse.
1
Fr
Incremental encoder with forward and reverse outputs.
With or without marker pulse.
2
Limitations
Type
Encoder
Max Input
Frequency
Max no. of
Lines (LPR)
Incremental
Ab
600kHz*
16,384
Fd
Fr
The maximum speed in rpm which an encoder connected to the SM-Encoder Plus can
reach can be calculated from :
Max rpm = (60 x Max input frequency) / Encoder LPR
e.g. For a 4096 line encoder the maximum rpm would be:
(60 x 600 x 10
3
) / 4096 = 8789rpm
NOTE
