EATON 91PS and 93PS Three-Phase UPS Hong Kong

The logic of this capacity band

The "mid" band is where UPS selection gets indecisive: single-phase models are running out of capacity, while a large modular frame is obviously oversized and unaffordable. The 91PS / 93PS class fills that gap. Three questions decide it:

Does the site have three-phase distribution? If yes, three-phase is cleaner and more efficient.
Will the load keep growing? If yes, choose an architecture with parallel expansion and redundancy headroom.
What does downtime cost? If high, design redundancy and a maintenance bypass in — do not look at unit capacity alone.

Installation scope

Site survey, load audit and capacity calculation
Distribution board capacity check, breaker and cable sizing
Phase rotation confirmation and earthing check
External maintenance bypass (recommended)
On-load testing and simulated mains-failure transfer test
Test records and a configuration note on handover

Maintenance afterwards

On a three-phase system the work concentrates on the battery bank and cooling. We provide scheduled inspection, discharge testing and full battery string replacement — optionally under an annual maintenance contract, so one team stays accountable and nobody has to argue about responsibility when something fails.

Key features

Three-phase online double-conversion — the output is fully isolated from the mains

A relatively compact three-phase chassis that fits an existing equipment room

Parallel redundancy and external battery expansion supported

Integrates with building monitoring and supports remote alarms

The natural step for a site moving from single-phase to three-phase

Where it fits

A site that already has three-phase distribution

With a three-phase feed in place, one three-phase unit is a cleaner answer than several single-phase units.

Growing out of single-phase

The load has outgrown single-phase models — move up while keeping room to expand.

Plant control centre

Backbone-grade backup for control systems and servers.

Frequently asked questions

When should I move from single-phase to three-phase?

Three common triggers: a single load is close to the ceiling of a single-phase model; the site already has three-phase distribution and clear expansion plans; or you need parallel redundancy. If the load has only grown slightly, check whether the problem is capacity or configuration — sometimes it is the latter.

What matters at installation?

Phase rotation, panel capacity, cable sizing and earthing. Get the rotation wrong and the unit alarms or will not run; undersize the supply or the cable and you get volt drop and heat. This is installation scope and we handle it, including on-load testing.

Can it connect to a larger system later?

Architecturally yes, but the expansion path has to be designed at the start. If growth is foreseeable, design for it now rather than replacing the whole set partway through.

Specifications

Capacity range	Mid-range three-phase models (by model — confirm with us)
Architecture	Three-phase online double-conversion
Input	Three-phase (confirmed against the site distribution)
Output waveform	Pure sine wave
Redundancy	Parallel redundant configurations supported
Runtime	Calculated from battery capacity and load
Typical sites	Mid-size machine rooms, critical equipment rooms, control centres

Specifications follow the manufacturer's latest data. Actual configuration must be sized against the site load, required runtime and distribution environment — this table is for selection reference only.

EATON 91PS / 93PS three-phase UPS