HP rp7400 Manual page 15

Specify Power Protection
The only supported HP PowerTrust UPSs are the 3.0kVA and 5.5kVA
models. These UPSs can provide power protection to a single rp7400
SPU. Recommendations for other manufacturers and models are not yet
determined.
HP rp7400 server power supplies may be plugged directly into the
customer's site UPS. However, customers are advised against plugging
the power supply into an HP PowerTrust UPS and then connecting that
UPS to the site UPS.
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