SAJ EK90 HS5-10K-S4-X (10 kW single-phase all-in-one)

The single-phase ladder runs from 5 kW to 10 kW, with a planning caveat for high-power connections in Germany.

• Sizes: 5 kW (4,999 W), 6 kW (plus a 5,750 W Ireland '-IE' variant), 8 kW and 10 kW (9,999 W)
• SAJ's own documents designate the 10 kW unit EK90 HS5-10K-S4-X, it has 4 MPP trackers instead of 3
• Distribution network operators limit unbalanced single-phase feed-in under the VDE-AR-N 4105 regime (typically to 4.6 kVA per phase), so the 8 kW and 10 kW single-phase units are aimed at markets and sites where a high-power single-phase connection is permitted, clarify with the DSO before specifying, or use the three-phase EK90 HS5 T3 line (8-20 kW) instead
• Check the datasheet model list: 220/230/240 V, 50/60 Hz, L+N+PE

Up to 6 stackable EK90 BU5 packs give configurable system capacities, with independent charge/discharge per pack.

• Packs: up to 6 stackable EK90 BU5 packs per system in 6 / 7 / 9 kWh sizes (LiFePO4, 314 Ah cells, 100% depth of discharge, usable = total energy)
• System capacity: configurable from 6 kWh up to 54 kWh; system battery voltage window is 300-600 V on the single-phase models
• Each pack has its own built-in DC-DC optimizer for fully independent charge/discharge, SAJ's "eliminates the wooden-barrel effect", allowing packs to be added later without the stack being dragged down by the weakest module
• Packs connect blind-mate, no inter-module cabling
• For a specific mixed-size combination, confirm against SAJ's battery-combination datasheet

Backup on the 10 kW model is built in, no separate retrofit box is required.

• Backup (EPS) output: EK90 HS5-10K-S4-X delivers 10000 VA continuous with a peak of 20,000 VA for 10 s for motor/compressor start-up, at a switchover time of ≤10 ms
• Whole-house backup path is built in: a 63 A bypass (current configurable in the elekeeper App) means no separate backup retrofit box is required
• SAJ's manual also describes a whole-home topology using a Lazzen NDQ2S-63/1P manual transfer switch (63 A/230 V) and a partial-backup wiring option where only selected circuits sit on the backup output
• The inverter integrates an RCMU, so an external on-grid RCD is optional, where local rules require one, use a type A RCD of 30 mA or higher
• Note: SAJ's EU datasheet and manual both state 63 A for the single-phase bypass

Treat it as a roadmap feature, not a shipping spec.

• The HS5 is designed around a bidirectional DC EV-charging module that SAJ positions as an "EV-Home-Grid energy bridge" (V2H/V2G)
• The single-phase EU datasheet explicitly footnotes the EVDC V2H & V2G capability as "currently under development and coming soon," and no DC charging power rating (kW) is published
• Do not quote a specific EV-charging output; if a project depends on bidirectional DC EV charging, confirm availability, part number and power rating with SAJ before committing, request a quote

Warranty

The EU datasheet and user manual state "refer to the warranty policy", no capacity-retention figure is published for this model, so quote warranty terms from SAJ's warranty document rather than a number.

• SAJ's HS5 product page headlines a 15-year warranty on the battery concept with the 314 Ah cell
• The manual rates the cells at 10,000 cycles (battery-manufacturer figure, 25±2°C) while the datasheet promotes 12,000 cycles under lab conditions (0.2C, to 60% SOH)

Monitoring

• Commissioning and monitoring run through the elekeeper App (3-step initialization, One-Click Self-diagnosis with meter & CT phase auto-adjustment) with an eSolar AIO3 Pro or eSolar 4G Pro communication module
• Metering uses the wiring-free dual-channel Wireless-pro LoRa meter (optimal 150 m through walls), with wired RS485 meter connections supported as a fallback