Siemens SIMATIC S7-1500 System Manual page 66

Example 1: Avoiding downtimes
Automation task
An automation solution is required for a road tunnel to:
• Control the lighting in the tunnel
• Control the ventilation in the tunnel in line with the concentration of pollutants in the
tunnel
Feature
Uninterrupted operation of the ventilation system is required to keep the concentration of
pollutants below a set level. Constant availability must be ensured for the event that
individual automation components fail, for example because of a fire in the tunnel.
Solution
Three fans (M) ventilate the tunnel. The automation solution controls the fan speeds in line
with the measured pollutant concentration. Three sensors in the tunnel measure the
pollutant levels in the air. The S7-1500H redundant system with two redundant CPUs is used
to ensure fan availability.
As well as controlling the fans, the S7-1500H redundant system also controls the illumination
and the traffic lights.
Figure 5-1 Example: Tunnel automation
Benefits
The user program for controlling the fans runs on both CPUs in the S7-1500H redundant
system. You can position the two CPUs up to 40 kilometers apart. If one CPU or one
redundancy connection fails due to a local incident, the incident does not affect the
controlled process. The fans continue to operate.
You can find a detailed description of tunnel automation with S7-1500H in Getting started
(https://support.industry.siemens.com/cs/ww/en/view/109757712) Redundant system S7-
1500R/H.
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF
5.1 What is the S7-1500R/H redundant system?
System overview
65