Smart-UPS 750 /NAS power on after **long** power failure

[BillP]

Hi,

Suppose there is a long power failure, and my UPS 750 becomes totally discharged (after shutting down required devices safely)
I have a NAS connected to the UPS which is set to power up automatically when power is eventually restored.

When power is restored:

1) Will the UPS automatically power on?
2) Will power be supplied to the NAS immediately?

It seems to me that If the NAS is powered up immediately, then it won't be protected against any subsequent power failure because the UPS is charging from completely flat. So if there's another power failure, the NAS might not have time to shut down safely.

It seems like in this scenario there needs to be a delay before any connected devices are powered by the UPS until the UPS has charged up sufficiently.

Thanks for your help.

Liz

[BillP]

Hi,

If your Smart-UPS 750 is a SMT or SMX model you can set a power on delay for the outlet group via the LCD panel. If your Smart-UPS 750 is an SUA you will need to install a network management card. From within the NMC you would be given the option to set a delayed power on.  

[BillP]

Thanks Bill,

My UPS is a SMT750IC

I don't believe it's possible to set the power on delay from the LCD panel, and I can find no mention of it in the manual.

However it can be set from Power Chute, so I temporarily connected my PC to the UPS so I could set it, then switched it back to the NAS.

All seems to work perfectly!

Thanks

Liz

[BillP · Accepted solution]

Hi,

To set the outlet group thresholds you need to change the menu from standard view to advanced view and the configure the outlet on delay. See pages 17 and 19 of the user's guide https://download.schneider-electric.com/files?p_File_Name=SU%20UM%20990-5442%20MN01%20EN.pdf&p_Doc_R...