8.1 System Configuration and Connection Example for SERVOPACK with Fully-closed Loop Control
8-5
8
Fu
lly-close
d L
oop
Co
ntro
l
(2) Analog Signal Input Timing
Input the analog signals with the timing shown in the following figure.
The /cos and /sin signals are the differential signals when the cos and sin signals are shifted 180
°
. The specifi-
cations of the cos, /cos, sin, and /sin signals are identical except for the phases.
The Ref and /Ref signals are input to the comparator. Input a signal that will exceed the hysteresis of the com-
parator (i.e., the broken lines in the following figure).
When they are crossed, the output data will be counted up.
∗1.
If the analog signal amplitude declines to approximately 0.35 V because of the differential amplitude, the serial con-
verter unit will output an alarm.
∗2.
This is the hysteresis width.
• Never perform insulation resistance and withstand voltage tests.
• When low-voltage analog signals are input to the serial converter unit, noise influence
on the analog signals affects the unit’s ability to output correct position information.
The analog cable must be as short as possible and shielded.
• Use the serial converter unit in a location without gases such as H
2
S.
• Do not connect or disconnect the unit while power is being supplied, or the unit may
be damaged.
• When using multiple axes, use a shielded cable for each axis. Do not use a shielded
cable for multiple axes.
• If you use any external encoder other than a recommended external encoder, evalu-
ate the system in advance before you use it.
100%
12.5%
75% max.
75% max.
12.5% min.
12.5% min.
Zero Point
Count-Up Direction
0.05 V
cos
(A+)
/cos
(A-)
sin
(B+)
/sin
(B-)
/Ref
(R-)
Ref
(R+)
*2
*1
SERVOPACK
origin pulse output position
12.5%
Ref and /Ref input
voltage range:
1.5 V to 3.5 V
cos, /cos, sin, and
/sin input voltage
range: 1.5 V to 3.5 V
0.2 V to 0.6 V
Rotation
