+ | Velocity |
| Index Velocity |
| Index Decel |
| Index Accel |
| Offset Distance |
| Time |
| Index Accel |
| Index Decel |
| Index Velocity |
- |
|
Index Initiate
Registration Sensor
Figure 47: Registration to Sensor Profile (Offset < 0)
5.4.4 Rotary Plus Index
A Rotary Plus Index is used when Rotary Rollover is active. The Rotary Plus Index is similar to an Absolute Index, but it is forced to go in the positive direction to get to its programmed position. The programmed position for a Rotary Plus Index must be within the Rotary Rollover range (Posn < Rotary Rollover). Figure 48 compares a Rotary Plus Index to an Absolute Index (Rotary Rollover is enabled).
Starting Position 0o
90o
180o
Rotary Rollover: 360o, Index Position: 270o
Position After Index
0o | 0o |
90o | 90o |
180o | 180o |
Rotary Plus | Absolute |
(Forced Positive) | (Shortest Path) |
Figure 48: Rotary Plus Index Profile
5.4.5 Rotary Minus Index
A Rotary Minus Index is used when Rotary Rollover is active. The Rotary Minus Index is similar to an Absolute Index, but it is forced to go in the negative direction to get to its programmed position. The programmed position for a Rotary Minus Index must be within the Rotary Rollover range (Posn < Rotary Rollover). Figure 49 compares a Rotary Minus Index to an Absolute Index (Rotary Rollover is enabled).
Starting Position 0o
90o
180o
Rotary Rollover: 360o, Index Position: 180o
Position After Index
0o | 0o |
90o | 90o |
180o | 180o |
Rotary Minus | Absolute |
(Forced Negative) | (Shortest Path) |
Figure 49: Rotary Minus Index Profile
5.4.6 Timed Index
A Timed Index is not a specific type of index like the other types listed above. Timed Index is simply an option for the other types of indexes. Each index type (other than registration indexes) can be configured as a Timed Index.
In many applications, the user knows how far the load must move in a certain period of time. Rather than making the user calculate an acceleration, velocity, and deceleration so that an index takes the right amount of time, the
In a Timed Index, the user provides the distance and time, and the firmware automatically calculates the accel, velocity, and decel to finish in the right period of time. Figure 50 shows an example of a Timed Index profile.
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