Load Shedding

[Anonymous user]

I have a new SMX3000RMLV2U (with a SMX120RMBP2U and AP9631 giving me 50 minutes of runtime at 60% load) and I want to use the 3 individually controllable Outlet Groups for Load Shedding.

1. I want to shutdown the UPS with 10 minutes of runtime remaining to be able to immediately power everything on, once power is restored, knowing i will have enough runtime remaining to shut everything down, should there be a secondary power outage. (The owner hates the idea of waiting for the battery to charge after power has been restored)
2. To accomplish this i want to Network PowerChute shutdown the servers on Outlet Group 3 after 10 minutes on battery, then power off.
3. Because the networking equipment draws very little power, I would like to keep all the networking equipment on Outlet Group 1 on, until there is only 10 minutes of runtime remaining, then power off.

I beleive I have Outlet Group 1 configured correctly. However I am unsure about Outlet Group 3. I would prefer NOT to configure Network PowerChute on each server, rather just using the Network PowerChute software defaults, and instead use the setting on the Network Management Card.

Please checkout my config and comment on what you think. THank you very much for your time. =D

Low Battery Duration: 5m
Maximum Required Delay: 5m
Basic Signaling Shutdown: No
Basic Low Battery Duration: 5m
Sleep Time: 0
On-Battery Shutdown Behavior: Restart

Outlet Group 1 - Network Equipment (Router, Firewall, Switches)
Power Off Delay: 5m
Reboot Duration: 8s
Power On Delay: 0
Min Return Runtime: 0
Turn Off Outlet Group when power failure lasts longer than: No
Turn Off Outlet Group when UPS runtime remaining is less than: 10m
Turn Off Outlet Group when UPS is overloaded: No
Skip outlet off delay: Yes
Stay off after power returns: No

Outlet Group 3 - Servers
Power Off Delay: 5m
Reboot Duration: 8s
Power On Delay: 0
Min Return Runtime: 5m
Turn Off Outlet Group when power failure lasts longer than: 10m
Turn Off Outlet Group when UPS runtime remaining is less than: 10m
Turn Off Outlet Group when UPS is overloaded: No
Skip outlet off delay: No
Stay off after power returns: No

Message was edited by: str1ct

[Anonymous user]

i think i found a flaw in my plan on Outlook Group 3.

If Min Return Runtime is 5m, and Turn Off Outlet Group when UPS runtime remaining is less than 10m could this cause a loop?

Lets say that some other Outlet Group, or any other unforeseen power draw, drains the battery down to 2 minutes of runtime, and then power is restored. Once the battery charges to 5 minutes or runtime Outlet Group 3 would be turned on. However because there is less than 10m of runtime remaining, then wouldn't it be immediately turned off, possibly looping like this over and over until there was at least 10m of runtime remaining?

Thoughts? Suggestions?

Thanks!

-mark

[Anonymous user]

to be clear... a PNCS signal will be sent 10 minutes after the UPS is on battery (or when less than 10 minutes of runtime is remaining), then 5 minutes later Outlet Group 3 will be turned off, effectively giving the PNCS clients on Outlet Group 3 the 5 minutes configured to properly shutdown before the power is turned off?

i read in the NMC users guide that "With PCNS v3.x, the Maximum Required Delay value is never used by the NMC for a UPS with outlet groups". that certainly relieves some of the confusion i had about how the Maximum Required Delay value would affect my Outlet Group 3. With that being true i dont understand why the Maximum Required Delay would be an option on a UPS with Outlet Groups? Wondering if you have any insight on that?

[BillP]

well after lengthy discussion here, i believe that could happen. what i think will avoid it is if you make your minimum return runtime 12 minutes so that you don't encounter any loops. that is 2 minutes more than you're runtime remaining threshold you've set and why we suggest that value.

[BillP · Accepted solution]

this document might be of good reference: http://www.apcmedia.com/salestools/NWHG-8ACJSR_R0_EN.pdf

Also, refer to PDF page ~41 here: http://www.apcmedia.com/salestools/PMAR-8P9G2C_R2_EN.pdf

the way i am seeing outlet group 3 (as long as PCNS 3.0.X is being used and each server knows what outlet group it is in) is that after any one of the load shedding conditions is met, so power failure longer than 10 minutes most likely, PCNS will be told to turn off and then apply a 5 minute delay before actually turning off.