Delta AS06XA-A - Page 615

Chapter 14 High Speed Counter Module AS02HC
14-17
14
Ring
Counter
2
31
-1
2
R es ol ut io n
0
Coun ter
value
-2
31
Zero
crossing
2
31
-1
0
-2
31
The absolute position
of SSI encoder
Ring counter
2
R es ol ut io n
counti ng up
counting
d own
Zero
crossing
Zero
crossing
Zero
crossing
9. Ring Counter Overflow / Underflow Detection
The Ring Counter Overflow/Underflow Detection function is enabled on the Alarm Setting tab page of the
HWCONFIG software. The alarm will appear as the counter value overflow/underflow occurs.
Ring counter
overflow
2
31
-1
-2
31
0
Counter
va lue
2
31
-1
-2
31
0
Ring counter
underflow
Counting up
Counting down
10. SSI Encoder Rotation Rate Restriction
For the SSI input counting, the rotation rate restriction is influenced by the SSI encoder resolution and monoflop time.
Use the corresponding formula in the following table to calculate the rotation speed of the SSI encoder.
Encoder type
Rotation rate (RPM)
Single-turn encoder
±

××

(tp: monoflop time, unit: us)
Multi-turn encoder
±
×
  
××

(tp: monoflop time, unit: us)
See the reference values for the formula above in the following table.
Monoflop time
(us)
Max. rotation rate
of single-turn encoders
(RPM)
Max. rotation rate
of multi-turn encoders
(RPM)
64 468750
468750
✕
2
MT data length
4000 7500
7500
✕
2
MT data length
8000 3750
3750
✕
2
MT data length
12000 2500
2500
✕
2
MT data length