[time-nuts] Help needed with a UPS for my GPSDO

[Dave]

Hi, I managed to find two second hand UPS at a ham rally but neither had 
a battery pack in it

One, an "APC backups-ups 400"Â  works well with a single 12V 7Ah sealed 
lead acid battery.

The other, an "APC SMART-UPS 600" seems to have space for two batteries.

I have found a manual for the "600" unit but it mentions nothing about 
the number of batteries or if they should be connected in series or 
parallel :-(

Has anyone any experience of these ??

Any help more than welcome.

Regards,
Dave