Find the family.
Then the exact fit.

1–52 kV; about 400–4,000 A; 16–63 kA; fused, breaker or contactor lineups

250 kW–100 MW; seconds-to-hours duration; UPS replacement, ride-through or behind-the-meter applications

0.5 kVA–5 MW system range; single phase below about 20 kVA, three phase above; scalable parallel systems

0.5 kVA–5 MW; VFI topology; tower, rack, modular and central systems

10 kW–5 MW system; module sizes commonly 10–250 kW; N+1/N+X

200 kVA–5 MVA per unit; flywheel/diesel rotary and motor-generator variants

1 kVA–5 MW; transformerless or transformer-based; single/three phase

5 kVA–6 MVA+; LV and MV systems; harsh-environment and DC plant variants

10 kW–5 MW per system; parallel plants tens of MW; lithium, VRLA and flywheel options

24/48/110/125/220 Vdc; about 1–1,000 kW; telecom, substation and industrial variants

100 kW–2 MW per unit; typically 10–60 seconds ride-through; parallel systems

5–1,000 kWh per cabinet/string group; VRLA, lithium-ion and Ni-Cd; matching DC bus required

1 kW–5 MW; 24–1,500 Vdc; 1/3 phase AC input; modular hot-swap variants

1 kVA–5 MW; 24–1,500 Vdc input; 120–690 Vac output; standalone or UPS module

16–6,300 A; 120–690 Vac; 1/3 phase; maintenance/automatic transfer configurations

16–6,300 A; wall, cabinet or switchboard integrated; make-before-break options

0.12 kW–7.5 MW+; 230 V–13.8 kV; Ex db/ec/eb/p, gas and dust groups

Small machine panels through multi-bay lineups; 24 Vdc controls to 690 Vac power; climate-controlled variants

LV through 38 kV commonly listed; complete lineups, cells and individual cubicles; higher HV rare

1 kVA–5 MW systems; battery age usually excludes batteries from valuation; modular parts often available

1–500 kVA commonly marketed; larger central systems through integrators; batteries usually new/replaced

Any electrical package; transformers, switchgear, generators, BESS, UPS and cooling are most realistic

Panels, cable, motors, drives, UPS and packaged equipment from over-order/cancellation

Donor transformers, breakers, motors, turbines, generators, UPS and controls; no standard size range