What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags

View all Tags

Set factory sensor state to down with greater than >



What is the formula for setting a factory sensor to down state using the greater than > symbol?

I have a channel in the factory sensor that counts the number of missing devices based on a number of expected devices and the number of actual connected/online devices.

I want the factory sensor to go in a down state when the channel has a value greater than 0. What is the formula I need to achieve this?

down factory-sensor greater-than

Created on Mar 14, 2018 2:38:09 PM

5 Replies



If you check out the manual page, there is a section on how to do formulas with comparisons.

PRTG Manual: Sensor Factory Sensor


Within a formula, the following elements are allowed to perform calculations with the values that are returned by one or more functions.

  • Basic operations: + (add), - (substract), * (multiply), / (divide)
    • Example: 3 + 5 * 2
  • Brackets: ( )
    • Example: 3 * (2 + 6)
  • Compare: = (equal), <> (not equal), > (greater), < (less), >= (greater or equal), <= (less or equal)
    • If the comparison resolves to true, the value is 10,000; if false, the value is 0. For delta sensors the speed is compared.

Created on Mar 15, 2018 5:27:04 AM by  Benjamin Day [Paessler Support] (1,441) 2 1

Last change on Mar 15, 2018 11:15:55 AM by  Luciano Lingnau [Paessler]




I already had the sensor factory working, but I was missing a formula to bring it to a down state when a specific number of devices is missing. I came up with the following:

  1. 1:If channel Missing devices is greater than 0, set the factory sensor to down state. channel(0011,3) > 0 status(0011)

Will this bring the sensor in a down state if the channel with ID #3 is higher than 0?

Created on Mar 15, 2018 8:22:21 AM



No, so the channel will let us know if it's a 0 or not. Then you'll set a threshold on that channel to when it's greater than 0, it puts the channel into a down state. Does this make sense?

Created on Mar 15, 2018 7:11:40 PM by  Benjamin Day [Paessler Support] (1,441) 2 1



Hello Benjamin,

That does make more sense. I have set the threshold as you described and it is working.

Created on Mar 16, 2018 7:58:31 AM



Glad to hear it!

Created on Mar 16, 2018 9:44:21 PM by  Benjamin Day [Paessler Support] (1,441) 2 1

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.