TR-Electronic CDV582 - Calculating Delay for Moving Axis

TR Safety – Preset Adjustment Function
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Page 76 of 91 TR-ECE-BA-GB-0163 v03 10/07/2020
10.3 Calculating the delay for a moving axis
If the preset adjustment function is executed while the axis is in motion, processing and run-times in
the control system and the speed of the measuring system play a major role for the delay between
preset execution and actually setting the value. The faster the axis moves, the greater the delay,
measured in revolutions.
The delay can also be expressed in steps when using the programmed Number of steps per
revolution.
The following example explains these facts in more detail.
Given:
- Programmed resolution = 8192 steps per revolution
- Speed: n = 3000 revolutions per minute
- Processing time in the controller: t
Control
= 100 ms (application-specific)
- Transmission time via EtherNet/IP™ network: t
EtherNet/IP
= 10 ms (application specific)
- Processing time in the measuring system: t
measuring system
≤ 10 ms
Wanted:
- Delay in revolutions and steps
The static delay time t
static
[ms] is a result of adding the processing times and the EtherNet/IP™
transmission time:
t
static
= t
Controller
+ t
EtherNet/IP
+ t
Measuring system
= 100 ms + 10 ms + 10 ms = 120 ms
The dynamic delay in revolutions V
dynamic
results from the static delay time multiplied by the speed:
V
dynamic
= t
static
* n =
0.120 s * 3000 rev.
= 6 rev.
60 s
The steps taken result from:
V
dynamic
* Resolution =
6 Rev. * 8192 steps
= 49152 steps
Rev.