<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Sensor Channels Settings

A sensor has one or more channels in which it handles the actual monitoring data. In the channel settings you can define how the data from the sensor's different channels will be displayed in graphs, gauges, and tables. Additionally, the channel data can determine the sensor's status. Use the limit settings to achieve this.

On the sensor's Overview page, click on the gear icon of a specific channel gauge to change its settings. A click on the pin symbol on the left of the gear icon in a gauge will make this channel the primary channel of the selected sensor.

You can alternatively call the settings of a channel by clicking on the respective gear icon in the channels data table underneath the gauges.

Note: For lookup channels, we recommend staying below 120 lookup values to get expressive gauges. For non-primary lookup channels, the upper limit is around 40 lookup values.

The Gear Icon of an SNMP Traffic Total Channel to Open Channel Settings

The available options are nearly the same for all sensor types. An exception applies to the "Downtime" channel which is automatically calculated and does not offer all settings. Channels with "absolute" values additionally have an option for defining the Value Mode. You can quickly choose another channel of the selected sensor via the dropdown list on the top of the settings dialog.

Channel Settings for a Memory Sensor

Available Channel Settings

Edit Channel "[Name]"
Name	Enter a meaningful name to identify the channel (not editable for script sensors after sensor creation). The name will be shown in graphs and tables. You can automatically add the sensor's ID to the name by using the placeholder [#id].
Unit	This field is only visible for script sensors, the SNMP Custom sensor, and the SNMP Library sensor. Enter a string describing the unit of the returned values. This is for display purposes only. Please enter a string.
Value Lookup	This field is only visible for script sensors, the SNMP Custom sensor, and the SNMP Library sensor. Select the lookup list to be applied to this channel's settings.
ID	The ID of the channel cannot be changed; it is used for unique definition. For example, you need the ID when using Sensor Factory sensors.
Display	Define where the channel will be displayed. Choose from: Show in Charts: The data of this channel will be shown in sensor graphs. Note: If you hide a channel here, it will also be hidden if this graph is used in a Report. Show in Tables: The data of this channel will be shown in sensor data tables. Note: If you hide a channel here, it will not be considered for the calculation of the "sum" (total) channel of this sensor! To change this setting, remove or add the check mark symbol in front of it.
Line Color	Define in what color the channel will be displayed in graphs. You can choose between Automatic Manual When you set this option to manual color definition please enter a color below.
Color (#rrggbb)	This option is only available if Manual is selected in the Line Color setting above. Please either enter a color in hexadecimal RGB notation (as in HTML/CSS), or choose a color from the visual color selector. The field containing the hexadecimal color value will change to the resulting color immediately in both cases.
Data	This setting is available for most channels. Define how data will be displayed. Choose between: Display actual values in [unit]: Display the values in the unit shown. Display in percent of maximum: Calculate and show percent values based on a maximum value. Provide a maximum below.
Maximum ([unit])	This field is only visible if the percent of maximum setting is selected above. Enter a value that will be regarded as maximum. Please pay attention to the given unit. All percent values will be calculated based on this value. Please enter an integer value.
Line Width	Define in what color the channel will be displayed in graphs. Enter an integer value in pixels. Although the line width is not limited, we recommend using values between 1 and 7 only in order to achieve optimal results.
Value Mode	This setting is only available for sensor channels which return absolute values. It is not available for sensors showing difference values, such as traffic sensors. Depending on this setting, the channel can not only show averages, but also minimum or maximum values in the graphs for the respective time spans. Choose between: Average: The channel shows average values. Minimum: The channel shows minimum values. Maximum: The channel shows maximum values. See section More for a description of each value mode.
Decimal Places	Define how many decimal places of the channel's data will be displayed in graphs and tables. Choose between: Automatic: Let PRTG choose how many decimal places will be used for optimal viewing results. All: Force display of all available decimal places. Custom: Manually define the number of decimal places. If you choose this option, an additional field will appear. Please enter an integer value there.
Spike Filter	A spike filter can be used to correct obviously faulty monitoring data. Sometimes, sensors report enormously high or far too low values; due to an error in data transmission, or due to incompatibilities of the physical device you are monitoring. This can make graphs unreadable. A spike filter can compensate for these flaws. When enabled values above and below a certain limit are disregarded in the monitoring data for graphs and tables. Note: The monitoring data itself will not be changed (but only the presentation of the data) and this setting is valid for all data of this channel (also the historic data). Choose between: Disable Filtering: Display all data as it is; do not filter out spikes. Enable Filtering: Enable a filter to remove spike values. Additional fields appear below. Note: The spike filter option is not available for the channel Downtime.
Spike Filter Max. Value [unit]	This field is only visible if spike filter is enabled above. Specify the maximum value allowed in the channel's data. All values above this value will be disregarded in graphs and tables. Please enter an integer value or leave the field empty.
Spike Filter Min. Value [unit]	This field is only visible if spike filter is enabled above. Specify the minimum value allowed in the channel's data. All values below this value will be disregarded in graphs and tables. Please enter an integer value or leave the field empty.
Vertical Axis Scaling	Define how the vertical axis for the channel is displayed in graphs. Choose between: Automatic Scaling: Let PRTG decide on the optimum scaling; usually ranging from the minimum to the maximum value. PRTG will use one single scale for each unit label only. Manual Scaling: Define the scaling manually. Additional fields appear below. Defining manual axis scaling can make low values better visible in your graph; but it may result in a chart with multiple vertical axis for the same unit label. Note: Settings for this option are ignored if Chart Type Stack channels on top of each other or Show in and out traffic as positive and negative area chart (available for traffic sensors) is enabled in the sensor's Settings tab.
Vertical Axis Maximum [unit]	This field is only visible if vertical axis scaling is enabled above. Specify the maximum value that will be used on the vertical axis for the channel. Enter an integer value.
Vertical Axis Minimum [unit]	This field is only visible if vertical axis scaling is enabled above. Specify the minimum value that will be used on the vertical axis for the channel. Enter an integer value.
Limits	The channel can affect the status of the sensor it is part of. By entering limits, you can define when the sensor will enter a Warning or Down status; depending on the channel's data. Using this function, you can e.g. set a traffic sensor (which is usually never in a down state) to error when certain limits that you consider critical are reached. Choose between: Disable Limits: Do not use the channel's data to control the sensor's status. Enable Limits: Define limits. Additional fields appear below. The sensor belonging to the channel will enter a Warning or Down status when limits are undercut or overrun. Note: The limits option is not available for the channel "Downtime". Note: If a channel uses lookups, we strongly recommend you to control the sensor status only via the lookup definition. If you define limits in addition here, the sensor will use both the channel limits and the status as defined in the lookup file. In this case, channel limits will determine the overall status of the sensor and overwrite the sensor message while the channel gauge still shows the status as defined in the lookups.
Upper Error Limit [unit]	This field is only visible if limits are enabled above. Specify an upper limit for an error state. If the channel's values overrun this value, the sensor will be set to Down. Note: While a sensor shows a Down status triggered by a limit, it will still receive data in its channels. Please enter a decimal value or leave the field empty.
Upper Warning Limit [unit]	This field is only visible if limits are enabled above. Specify an upper limit for a warning state. If the channel's values overrun this value, the sensor will be set to Warning. Please enter a decimal value or leave the field empty.
Lower Warning Limit [unit]	This field is only visible if limits are enabled above. Specify a lower limit for a warning state. If the channel's values undercut this value, the sensor will be set to Warning. Please enter a decimal value or leave the field empty.
Lower Error Limit [unit]	This field is only visible if limits are enabled above. Specify a lower limit for an error state. If the channel's values undercut this value, the sensor will be set to Down. Note: While a sensor shows a Down status triggered by a limit, it will still receive data in its channels. Please enter a decimal value or leave the field empty.
Error Limit Message	This field is only visible if limits are enabled above. Enter an additional message. It will be added to the sensor's message when entering a Down status. Please enter a string or leave the field empty.
Warning Limit Message	This field is only visible if limits are enabled above. Enter an additional message. It will be added to the sensor's message when entering a Warning status. Please enter a string or leave the field empty.

Click on Save to store your settings and to close the settings window. With a click on Apply changed settings will be stored and the settings window remains open. This functionality is useful if you want to change the settings of other channels of the current sensor as well. You can then select another channel via the drop-down menu on top of the settings window. You can Close the settings window with a click on this button.

Note: If you have changed any settings and click on Close or choose another channel via the drop-down menu without applying the changes, PRTG will ask you to confirm this step. Discard Changes will ignore any edits and closes the window or shows the settings of another selected channel respectively. Click on Save to apply your changes.

Knowledge Base: What is the Value Mode in channel settings?

http://kb.paessler.com/en/topic/60238

Sensor Settings Overview

For information about sensor settings, please see the following sections:

Ajax Web Interface—Device and Sensor Setup—Topics

Other Ajax Web Interface Sections