Delaying AX150 autoshutdown on Power Failure

Good Afternoon,

I am running ESX 3.5 on 3 PE2950's connected to an AX150i DP with the external UPS.  I had an issue this morning where we had a quick power failure in the building that lasted about 3 mins.  The issue I had was that as soon as the ax detected that its UPS was running on battery the ax instantly started emptying cache and started the shutdown process.  My esx servers are connected to a apc symetra and they stayed up because the outage was so fast yet all my network services on the vm's stopped working and the vm's gave me an error in Virtual Center that the config file could not be found. Once the power was restored the ax fired itself back up and the vm's came back up but I would prefer it waits a few minutes until it starts this shutdown process. Most of my power outages usually do not last longer then a minute or two. It there any way that I can delay the ax from beginning its shutdown process until I can have powerchute shutdown the vm's.  It appeared that powerchute wouldnt have enough time to shutdown every vm as some of them take a few mins to shut down before the ax was down.  The only solution I can see is to plug the UPS and the other ps for the AX into one of the power outlets on my apc symetra so the AX ups does not realize it is running on battery until the symetra is drained.  I have read in the AX docs where they mention specifically not to do this though.  Any help would be appreciated

Thanks

Rich