APC REMOTE POWER-OFF DEVICE AP9830 - Manual (Page 23)

20 Remote Power-Off Device — Installation and Quick Start
How to Turn Off the Output of Multiple UPSs
To set up more than one APC UPS to turn off from one remote
switch, you must have one Remote Power-Off Device for each
UPS. You can set up remote turnoff of multiple UPS outputs in
either a cascading (serial) configuration or (for voltage input
switches only) a parallel configuration.
Cascade
multiple RPOs
(serial setup) You can set up either type of remote switch (contact closure or
voltage input) by cascading Remote Power-Off Devices.
Warning
To connect multiple UPSs to a system that uses
contact closures to turn off the UPSs, you must
provide a separate set of contact closures for
each UPS. Do not set up multiple UPSs in a
parallel configuration to a single set of contacts.
A parallel configuration can introduce
intersystem ground noise or generate false EPO
signals at the integrated EPO interface of a
UPS or at the Remote Power-Off Device.
UPS 1 UPS 2
UPS
n
Connection to remote switch