AXIOMTEK MVS900-511-FL Series, Руководство пользователя

Страница: 47 / 80

MVS900-511/512-FL
Operating 41
Section 4
Operating
4.1 Operating
This section describes the detail operation of the MVS900.
4.1.1 Encoder function
The MVS900 supports 2CH 32-bit incremental quadrature encoder input for the ABZ signal by
a mode x1, x2 or x4, which is used for applications where direction sensing is required. This
mode consists of two square-wave pulse signals known as Phase A and Phase B, which are
generated by a rotating encoder. Phase A and Phase B signals are coded 90° out of phase
from each other: Phase A is either 90° phase leading or lagging behind Phase B. The MVS900
is able to count square-wave pulses of Phase A and Phase B, and then determine the rotating
direction of motor movement by comparing the phase relationship between Phase A and B:
 When the quadrature encoder is rotating in a clockwise direction, its signal will show a
positive direction of Phase A leading Phase B.
 When the quadrature encoder rotates counterclockwise, its signal will show a negative
direction of Phase A lagging behind Phase B.
Besides direction, the quadrature encoder can generate another signal named Phase Z, which
is produced once per complete rotation of the quadrature encoder. Phase Z is used by the
MVS900 to locate a position of the motor when the quadrature encoder completes a 360°
rotation, so that the counter value of Phase Z can reset to zero if the configuration set the
homing conditions.
 Counter mode
x1 mode: The counter value will increment or decrement when a rising edge happens on
Phase A.
x2 mode: The counter value will increment or decrement when a rising edge or a falling edge
happens on Phase A.
x4 mode: The counter value will increment or decrement when a rising edge or a falling edge
happens on Phase A or B.
In most cases, the x4 Phase AB signal mode is applied to incremental encoder devices. For
example, when a motor completes a 360° rotation, an incremental encoder will generate 1000
pulses per phase (A or B phase), but the count will show 4000 pulses.
1/2 mode: The counter value will increment or decrement when a rising edge happens twice
on phase A.
1/3 mode: The counter value will increment or decrement when a rising edge happens three
times on phase A.
1/4 mode: The counter value will increment or decrement when a rising edge happens Four
times on phase A