PRTG Manual: SIMATIC S7-1200/1500 CPU Status Sensor

Enabled Beta Sensors experimental feature

This sensor requires that the Beta Sensors experimental feature is enabled.

For more information, see the Knowledge Base: What are beta sensors and how can I use them?

S7 Web API

Requires S7 Web API to be enabled on the device.

Credentials

This sensor requires credentials for the S7 Web API in settings that are higher in the object hierarchy. Additionally, the user account must have read_diagnostics permissions.

Scanning interval

This sensor has a fixed minimum scanning interval for performance reasons. You cannot use a shorter scanning interval. Consequently, shorter scanning intervals in the Monitoring settings are not available for this sensor.

• The minimum scanning interval of this sensor is 1 minute.
• The recommended scanning interval of this sensor is 1 minute.

IPv6

This sensor supports IPv6.

Performance impact

This sensor has a very low performance impact.

Lookups

This sensor uses lookups to determine the status values of one or more channels.

Limits

This sensor has predefined limits for one or several metrics.

Primary Channel

Select a channel from the list to define it as the primary channel. In the device tree, PRTG displays the last value of the primary channel below the sensor's name. The available options depend on what channels are available for this sensor.

You can set a different primary channel later by clicking below a channel gauge on the sensor's Overview tab.

Graph Type

Define how this sensor shows different channels:

• Show channels independently (default): Show a graph for each channel.
• Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This generates a graph that visualizes the different components of your total traffic.
  You cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).

Stack Unit

This setting is only visible if you select Stack channels on top of each other above.

Select a unit from the list. PRTG stacks all channels with this unit on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so.

Result Handling

Define what PRTG does with the sensor result:

• Discard result (default): Do not store the sensor result.
• Store result: Store the sensor result and the last response in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file name is Result of Sensor [ID].log. This setting is for debugging purposes. PRTG overwrites this file with each scanning interval.

This option is not available when the sensor runs on the hosted probe of a PRTG Hosted Monitor instance.

In a cluster, PRTG stores the result in the PRTG data directory of the master node.

Communication Load

The current communication load of the CPU (%)

Communication Load Ratio

The current communication load in relation to the configured maximum communication load (%)

Current Cycle Time

The duration of the most recent program cycle

Cycle Time Events

If the Cycle Time Exceeded event occurred

• Up status: OK
• Warning status: Diagnostic Buffer Overflow
  Diagnostic Buffer Overflow happens when the number of events surpasses the diagnostic buffer limit between sensor scans, which prevents PRTG from finding the last known event. The events PRTG cannot detect might include a Cycle Time Exceeded event.
• Down status: Cycle Time Exceeded
• Unknown status: Unknown

Longest Cycle Time

The longest program cycle time that the CPU measured

Mode Selector

The position of the mode selector of the CPU

• Up status: RUN
• Warning status: STOP, UNKNOWN
  PRTG distinguishes between two different unknown states for this channel: UNKNOWN indicates that the PLC could not determine the position of the mode selector, while Unknown indicates that PRTG has not received any data yet.
• Unknown status: Unknown, No Switch

Mode Selector (R2)

This channel is only available for redundant PLCs.

The position of the mode selector of the second CPU in a redundant setup (R2)

• Up status: RUN
• Warning status: STOP, UNKNOWN
  PRTG distinguishes between two different unknown states for this channel: UNKNOWN indicates that the PLC could not determine the position of the mode selector, while Unknown indicates that PRTG has not received any data yet.
• Unknown status: Unknown, No Switch

Operating Mode

The operating mode of the CPU

• Up status: RUN, RUN REDUNDANT
• Warning status: STARTUP, HOLD, STOP SELF-INITIALIZATION, SYNCUP, RUN SYNCUP, REMOTE UNKNOWN, ERROR SEARCH
• Down status: STOP
• Unknown status: Unknown

This channel is the primary channel by default.

Operating Mode (R2)

This channel is only available for redundant PLCs.

The operating mode of the second CPU in a redundant setup (R2)

• Up status: RUN, RUN REDUNDANT
• Warning status: STARTUP, HOLD, STOP SELF-INITIALIZATION, SYNCUP, RUN SYNCUP, REMOTE UNKNOWN, ERROR SEARCH
• Down status: STOP
• Unknown status: Unknown

Program Load Cyclic OBs

The load that cyclic program organization blocks (OBs) cause (%)

This channel has default limits:

• Upper warning limit: 80%

• Upper error limit: 100%

Program Load High-Priority OBs

The load that high-priority program organization blocks (OBs) cause (%)

Shortest Cycle Time

The shortest program cycle time that the CPU measured

Downtime

In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status.