Delta AS Series Manual page 615

2
2 R es ol utio n
Counter
value
Ring
Counter
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.
31
2 -1
Counter
0
value
31
-2
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
Single-turn encoder
Multi-turn encoder
See the reference values for the formula above in the following table.
Monoflop time
(us)
64
4000
8000
12000
Ch ap te r 14 H igh Spe ed Cou n te r Mod ul e AS02HC
31
-1
Zero Zero
crossing crossing
0
31
-2
Ring counter
overflow
Counting up
±
60
2×tp×10
−6
(tp: monoflop time, unit: us)
±
60×2
MT data length
2×tp×10
−6
(tp: monoflop time, unit: us)
Max. rotation rate
of single-turn encoders
(RPM)
468750
31
2 -1
2 R es ol utio n
counting up
0
31
-2
31
2 -1
0
31
-2
Rotation rate (RPM)
7500
3750
2500
Zero Zero
crossing crossing
counting
down
The absolute position
of SSI encoder
Ring counter
Ring counter
underflow
Counting down
Max. rotation rate
of multi-turn encoders
(RPM)
✕
468750 2 MT data length
✕
7500 2 MT data length
✕
3750 2
MT data length
✕
2500 2 MT data length
1 4 - 1 7
14