Siemens SIMATIC S7-1500R/H Getting Started page 30

Setting the watchdog time
Do not enter the watchdog time directly, but as "Accepted number of update cycles when IO
data is missing". The resulting watchdog time is automatically calculated from the "Accepted
number of update cycles when IO data is missing".
1. Select an interface module IM 155-6 PN HF.
2. Navigate to "Properties" > "Advanced options" > "Real time settings" > "IO cycle" >
"Watchdog monitoring".
3. Set the update cycles for the example to 112 (224 ms).
Figure 2-10 Setting the watchdog time
4. Follow steps 1. to 3. for the other two interface modules IM 155-6 PNHF (tunnel sections
2 and 3).
S7-1500R/H redundant system
Getting Started, 10/2018, A5E44910930-AA
Configuration
2.3 Configuring ET 200SP
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