Installation guide

Estimating Network Performance

890 USE 100 00

For example.consider twocases in which an MSTR is enabled every

scan, and the scan time is 20 ms.

V Faster token If the token rotation time is estimated at 10 ms, count

the Data Master path use as 0.5 path. The ratio (10/20) shows the

use is onehalf path.

V Faster scan If the token rotation time is estimated at 50 ms, count

the Data Master path use as 1.0 path. Even though the ratio

(50/20) is greater than unity, the use will never be more than one

path.

Note: First estimate of the token rotation time and then refine it

after you perform the calculation. Use the chart in Figure 35 to make

the estimate.

For example, if an MSTR block will be timed to execute every 500 ms,

and the token rotation time is estimated as 50 ms, you can estimate the

Data Master path use as 0.1 path (50/500). After you calculate the

actual token time from the formula, review your initial estimate. If the

actual time is not close to 50 ms, refine your estimate and recalculate

the path use.