SAJ EK90 HS5-5K-S3-X (5 kW single-phase all-in-one)

The single-phase ladder covers 5 kW to 10 kW, but check the DSO limit before specifying the top of the range for 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)
• Naming note: SAJ's own documents designate the 10 kW unit EK90 HS5-10K-S4-X, which has 4 MPP trackers instead of 3
• Germany planning caveat: 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
• Alternative: clarify with the DSO before specifying, or use the three-phase EK90 HS5 T3 line (8-20 kW) instead
• Electrical spec: 220/230/240 V, 50/60 Hz, L+N+PE

Up to 6 stackable EK90 BU5 packs per system, giving configurable capacities from 6 kWh to 54 kWh.

• Pack sizes: 6 / 7 / 9 kWh (LiFePO4, 314 Ah cells, 100% depth of discharge, usable = total energy)
• System voltage window: 300-600 V on the single-phase models
• Independent modules: each pack has its own built-in DC-DC optimizer for fully independent charge/discharge, what SAJ calls "eliminating the wooden-barrel effect," which is what allows adding packs later without the stack being dragged down by the weakest module
• Wiring: packs connect blind-mate, no inter-module cabling

For a specific mixed-size combination, confirm against SAJ's battery-combination datasheet.

Backup (EPS) output on the EK90 HS5-5K-S3-X is 5000 VA continuous with no separate backup box required.

• Peak rating: 10,000 VA for 10 s, for motor/compressor start-up
• Switchover time: ≤10 ms
• Built-in bypass: a 63 A bypass (current configurable in the elekeeper App) covers whole-house backup, so no separate retrofit box is required
• Whole-home topology: SAJ's manual also describes 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
• RCD: 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.

• Design intent: the HS5 is built around a bidirectional DC EV-charging module SAJ positions as an "EV-Home-Grid energy bridge" (V2H/V2G)
• Current status: the single-phase EU datasheet explicitly footnotes the EVDC V2H & V2G capability as "currently under development and coming soon", with no DC charging power rating (kW) published
• Guidance: 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

• Monitoring and commissioning run through the elekeeper App (3-step initialization, One-Click Self-diagnosis with meter & CT phase auto-adjustment)
• Communication via an eSolar AIO3 Pro or eSolar 4G Pro 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