Clear Fault Light and Remove Power Supply 2 Alarm on Hirschmann Managed Switch

Hirschmann Managed Switches have redundant power supply inputs which are a great feature; however, many users don’t take advantage of them for a variety of reasons. In these cases, the unused benefit can become a nuisance. This is because by default, the managed switch monitors for power on both Power Supply 1 and Power Supply 2 inputs and flags it as a fault when either is missing. This fault is presented as both a red fault light on the front of the switch, and as an alarm in the Web Management of the switch. There are three solutions to this issue:

1) Take full advantage of the feature and provide secondary power to the switch. 

2) Jumper Power Supply 1 to Power Supply 2 to “trick” the switch into thinking secondary power is connected. 

3) Disable monitoring of Power Supply 2 through the Web Management of the switch.
 
I’m going to show you how to accomplish #3. First, let’s look at the alarm in question. On the Basic Settings>System Page, you see we have a nasty red alarm indicating Power Supply 2 failure.


To disable the monitoring, let’s visit the Diagnostics>Device Status page. Here, we will modify the Monitoring Status of Power Supply 2 from “Monitor” to “Ignore” and then hit Set down at the bottom of the page.


If you’re near the switch, you’ll hear and see the fault light click off. Similarly, if we go back to the Basic Settings>System page we see that the alarm has cleared.


Also, If you’re using the Signal Contact output of the switch, you need to make a similar change on the Diagnostics>Signal Contact page as shown below:


Finally as always, don’t forget to save your changes to NVRAM before leaving the switch. Basic Settings>Load/Save>Save-ToDevice>Save!