APC Pro 550 switches to battery and dies when Data Port connected

[ppetrelli_apc]

This was originally posted on APC forums on 7/30/2020

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Hello!

I just got a used APC Pro 550 and connected my NAS to the UPS.

As i have some multiple devices that should shut down on their own i wanted to install N.U.T. on a raspberryPi and connect my devices to it.

And here my troubles begin: as soon as i connect the UPS-dataport to my raspberry the UPS switches to battery and soon after dies and restarts. When i boot my NAS up again after some seconds the UPS switches to battery again...

Am i missing something (configuration-wise) or is it a hardware problem?

any help would be appreciated!

[BillP]

This reply was originally posted by Bill on APC forums on 7/31/2020

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Hi,

Have you tried to connect the UPS to a Windows system or Mac and if you do is the UPS discovered and does it stay on line?

[ppetrelli_apc]

This was originally posted on APC forums on 8/4/2020

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Hi!

Sorry it took so long, had to find the time to get the UPS to my windows machine.

Connected both surge and data, seems stable, UPS is recognised as HID-USV-Akku (German).

huh - strangest thing: i connected the same Raspberry to the same output and to the data-port and... no shutdown.

i can't test very much with my NAS because these dirty poweroff can't be good for the drives 😞

[ppetrelli_apc · Accepted solution]

This was originally posted on APC forums on 8/12/2020

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no ideas?