Server restarts when switching to battery

[Anonymous user]

HI Folks,

I just purchased a 2nd hand UPS (Smart-UPS 1400VA 2U) with new batteries.

I have 4 servers connected to it. When I pull the utility power from the UPS, 3 of my servers are fine however the Dell Poweredge R200 restarts (as if the power isn't being flipped over quick enough..)

The other 2 servers are HP and the 1 other is a VIA EPIA firewall (They are fine).

I used to have another Smart-UPS 1400VA (but not the rack version) and it as fine..

Help is appreciated cheers.

P.S. I'm not using PowerChute

[Anonymous user]

Ok I narrowed it down a bit...

If you look at my post above, I have 2 HP servers. They are different models.

If I disconnect the ML310G5 HP server, the Dell stays on no problem. Even if I replace the ML310G5 with my desktop Core2 Quad Q6600 and pull the plug, the Dell stays on ok when the plug is pulled.

It's as if the PSU of the ML310G5 is interfearing with the Dell's ability to withstand the "flip-over to battery"...

Any ideas?

Cheers

[Anonymous user]

Ok just trash my theory on the HP server causing problems.

Just seems to be the Dell having issues with this UPS...
Sometimes it stays on..sometimes it reboots...

[BillP]

one other thing that i will throw out there could be transfer time to and from battery.

regular Smart UPS (not SC or RT families) take about 2-4ms to transfer to battery. a lot of high end, sensitive equipment cant take this and may reboot or turn off. i cant say from experience that i see it a lot with Dell servers but i will just mention it. if it were the case, it may be require a UPS with 0ms transfer time, such as a Smart UPS RT.

but before we assume that, since I dont think it's the case, do you have another UPS to try this server with? also, does this server have redundant power supplies?

[TheNotoriousKMP_apc]

jonnytabpni wrote:
Someone else suggested to me that due to the inital surge on the UPS when switching to battery, the waveform may be less that what the Dell server can handle. This is probably due to worn capacitors or something.

I'm waiting on an APC Line-R to see if that fixes the issue. I'm going to put it between the UPS and the Dell Server.

I don't think that's going to matter. There is no initial surge when transferring to battery, but there is that 2-4 ms blackout time. So it goes from AVR corrected input power to blackout to battery power (pure sine) in that period of time. If the Server works fine on another Smart-UPS, then I'd say the UPS is the problem, and it's probably just worn due to age. However, I don't see the Line-R doing anything for you since it's going to regulate the voltage, and if it's a "surge" as you've been told, the Line-R output is going to be 0VAC.

[Anonymous user]

Oh I forgot to mention that I tried the UPS with the only thing plugged in being the Dell and it's all fine...

I'm kinda hoping that the Line-R will add some extra capacitance just enough to let the Dell server hold out long enough.
I don't understand why the Dell server is the only one causing an issue when all the servers are on the UPS...

[Anonymous user]

Thanks for your reply.

As noted above, I do have another APC UPS (Smart-UPS 1400VA non-rackmount) and the Dell Server is fine with it.

Someone else suggested to me that due to the inital surge on the UPS when switching to battery, the waveform may be less that what the Dell server can handle. This is probably due to worn capacitors or something.

I'm waiting on an APC Line-R to see if that fixes the issue. I'm going to put it between the UPS and the Dell Server.

I know APC don't reccomend daisy chaining surge protection devices however the Smart-UPS is a true Sine Wave machine so it shouldn't be anywhere near as bad as a stepped-approx'ed one.

Any comments?

Cheers 🙂

[BillP]

how many load LEDs are lit up on the UPS with everything connected?

just for the heck of it, did you try the Dell server COMPLETELY alone - I noticed you tried it with your desktop and one of the other servers...

[Erasmus_apc]

Do you have a network management card free that you could install in the UPS? Or...could you install our PowerChute software with no shutdown options enabled just to check on some of the data and events?

Are you using any daisy chained extension cords, surge protectors, or other UPS-type products in your configuration?

Finally...I notice from your other posts that you are using mainly international units. What is the exact model # on this UPS and do you know the power specs on the servers you plugged in?

[Anonymous user · Accepted solution]

I'm sorry I don't have a management card and I can't use powerchute as I don't have the APC serial cable.

I am using a surge protector daisy chained onto the UPS however disconnecting it still causes the problem.

The 2 HP servers and 1 Dell (problem) server is plugged directly into the UPS with the surge protect daisy chain being used for the firewall, switches, modems etc..

Where can I find the serial number of this unit?

Overall, using my power meter, the whole rack takes up about 360W.

What really gets me is that the HP servers seem happy as anything!

I havn't tried the Dell completly alone. I will do that in a couple of hours when I can take the rack down as it is being used currently.
With everything connected, 2 load LEDs light up

Message was edited by: jonnytabpni