Dyness Tower T21
Verified distributor global (EN documentation); also sold in the US via dyness.us verified Sept. 2, 2026
Unresolved safety-relevant conflict
Two sources give different figures for a value on this product and nobody has resolved it. The specifications below are shown as recorded, but this product must not be treated as verified for engineering purposes until the conflict is closed.
Two sources give different figures for a value on this product and nobody has resolved it. The specifications below are shown as recorded, but this product must not be treated as verified for engineering purposes until the conflict is closed.
Identity
| category | batteries |
| ean | UNKNOWN |
| generation | 1.5g |
| hardware_revision | Tower 1.5g (per the user manual title) |
| legacy_name | UNKNOWN |
| manufacturer | Dyness (Dyness Digital Energy Technology Co., LTD) |
| market_version | EN |
| model | Tower T21 |
| mpn | UNKNOWN |
| product_family | Dyness Tower (T7 / T10 / T14 / T17 / T21, 192-576 V HV) |
| product_status | UNKNOWN |
| product_status_detail | current |
| product_status_evidence | Live official product page with a full specification table at https://dyness.com/tower-high-voltage-storage-battery-for-household-use (accessed 2026-09-02), and Tower T21 is listed for sale on the official Dyness USA store dyness.us. Counter-evidence: the ONSA Plus retailer blog (30.06.2026) states 'The original Tower (T7-T21) series is being phased out and sold while stocks last.' - recorded as a conflict. |
| region | global (EN documentation); also sold in the US via dyness.us |
| release_year | UNKNOWN |
| sku | UNKNOWN |
| subcategory | high-voltage residential stacked battery SYSTEM (BDU control unit + N battery modules + base) |
| variant_note | SYSTEM-level record. Tower T21 = 6 x HV9637 battery modules on one BDU control module plus a base. The 21.31 kWh / 576 V figures are SYSTEM figures, not module figures (the module is 96 V / 37 Ah / 3.552 kWh - see the separate HV9637 record). |
Electrical
| cell_chemistry | LiFePO4 (manual: 'LFP' / 'Li-ion (LFP)') |
| cell_type | UNKNOWN |
| continuous_charge_current_a | 18.5 |
| continuous_discharge_current_a | 18.5 |
| continuous_power_kw | 12.78 |
| cycle_life | 6000 |
| depth_of_discharge_pct | 95 |
| max_charge_current_a | 37 |
| max_charge_power_kw | 12.78 |
| max_discharge_current_a | 37 |
| max_discharge_power_kw | 21.31 |
| max_parallel_units | 12 |
| max_series_units | 6 |
| modules_per_tower_max | 6 |
| modules_per_tower_min | 2 |
| nominal_capacity_ah | 37 |
| nominal_energy_kwh | 21.31 |
| nominal_voltage_v | 576 |
| operating_voltage_max_v | 657 |
| operating_voltage_min_v | 504 |
| parallel_supported | True |
| peak_charge_current_a | UNKNOWN |
| peak_discharge_current_a | UNKNOWN |
| peak_power_kw | UNKNOWN |
| round_trip_efficiency_pct | UNKNOWN |
| series_supported | True |
| system_energy_max_kwh | 255.72 |
| system_energy_min_kwh | 7.1 |
| usable_energy_kwh | 20.245 |
Physical / mechanical
| color | White |
| cooling_method | UNKNOWN |
| depth_mm | 380 |
| enclosure_material | UNKNOWN |
| height_mm | 1500 |
| installation_notes | Tower Pro/Tower user manual clearance guidance: 300 mm minimum clearance around the enclosure. Total weight includes the BDU control module and the base, which are counted separately from the battery modules. |
| ip_rating | IP54 |
| mounting_type | floor-standing stacked tower (BDU control module on top of N stacked battery modules, on a base) |
| rack_units | UNKNOWN |
| shipping_weight_kg | UNKNOWN |
| weight_kg | 269 |
| width_mm | 504 |
Installation
| clearance_notes | 300 mm minimum clearance is shown in the Dyness tower installation clearance diagrams |
| indoor_outdoor | indoor and outdoor (IP54) |
| notes | The BDU control module and the base are mandatory, are ordered separately from the battery modules, and their mass is included in the quoted tower net weight. Modules are stackable with auto-configuration / wireless connection per the official product page. |
| parallel_hub_required | UNKNOWN |
Environment
| indoor_outdoor | indoor and outdoor (IP54) |
| max_altitude_m | UNKNOWN |
| operating_humidity | UNKNOWN |
| operating_temperature_charge_max_c | 50 |
| operating_temperature_charge_min_c | 0 |
| operating_temperature_discharge_max_c | 50 |
| operating_temperature_discharge_min_c | -10 |
| operating_temperature_max_c | 50 |
| operating_temperature_min_c | -10 |
| pollution_degree | II (battery module table) |
| storage_humidity | <65% RH |
| storage_temperature_max_c | 45 |
| storage_temperature_min_c | 5 |
Interfaces & connectors
| bluetooth | UNKNOWN |
| can | True |
| communication_ports | BDU 'EXT-CAN/RS485' RJ45 to inverter; composite 9-pin connectors between BDU and battery modules; parallel ports for multi-cluster |
| dry_contact | UNKNOWN |
| ethernet | UNKNOWN |
| modbus_rtu | UNKNOWN |
| modbus_tcp | UNKNOWN |
| protocol_notes | EXT-CAN/RS485 pinout: PIN1 Orange/White 485_A, PIN2 Orange 485_B, PIN3 Green/White Reserved, PIN4 Blue CANH, PIN5 Blue/White CANL, PIN6 Green CANIN, PIN7 Brown/White CANOUT, PIN8 Brown NC |
| rs232 | Datasheet 'Communication' row reads 'CAN/RS485/RS232'; the user manual documents only CAN/RS485 pins on the BDU EXT port |
| rs485 | True |
| usb | UNKNOWN |
| wifi | UNKNOWN |
Protection
| fire_suppression | UNKNOWN |
| notes | Manual Table 2-1 'Short circuit current [kA]' = 1.5. Manual protection chapter also requires a 30-minute wait before resetting a tripped DC breaker. |
| overcurrent | Datasheet 'Protection Features': Overcharge/Overdischarge/Overcurrent/Overtemperature/Short Circuit |
| short_circuit_current_ka | 1.5 |
Certifications
| emc_certifications | CE-EMC |
| safety_certifications | IEC62619 / IEC63056 / IEC62477 / IEC62040 / IEC60730 / VDE2510-50 / UL1973 / UKCA / CEC Accredited |
| standards | UN38.3/CE-EMC/IEC62040/IEC62619/IEC62477/IEC60730/IEC63056/UKCA/CEC Accredited/UL1973/VDE2510-50 |
| transport_certifications | UN38.3 |
Warranty & service
| conditions | UNKNOWN |
| summary | No warranty period is printed in the fetched Tower datasheet, user manual or product page for this model. The 7SUN listing for the Tower BDU control module quotes a 10-year warranty. |
| years | UNKNOWN |
Documents
compatibility_list
List of the Inverter Brands Compatible with Dyness Tower Series, last updated 06/05/2025 - distributor mirror on vanmeenen.com
rev 250506
datasheet
{# Located but never retrieved: listed, but deliberately not linked, and it
backs no stored value. #}
Dyness Tower datasheet EN 2025-04-22 (TowerDatasheetEN20250422-281.pdf) - official, linked from the Tower product page — located, not retrieved
rev 2025-04-22
datasheet
Dyness Tower datasheet-EN V1.0-20230704 - distributor mirror on estsolar.lt
rev V1.0-20230704
retailer_article
ONSA Plus retailer blog: 'The Dyness Tower is ending: move to Tower Pro and Stack' (published 30.06.2026)
rev UNKNOWN
Recorded conflicts
electrical.nominal_energy_kwh / electrical.usable_energy_kwh (label semantics) Review required
21.31 kWh labelled 'Total energy stored' with a separate 'Usable energy' of 20.245 kWh — Tower 1.5g User Manual EN, Table 2-1
21.31 kWh labelled 'Usable Energy' — Dyness Tower datasheet-EN V1.0-20230704 (distributor mirror: estsolar.lt)
identity.product_status Review required
current - a live official product page with a full spec table exists on dyness.com — Dyness Tower official product page
being phased out - 'The original Tower (T7-T21) series is being phased out and sold while stocks last.' — ONSA Plus retailer blog, 'The Dyness Tower is ending: move to Tower Pro and Stack' (30.06.2026)
electrical.max_parallel_units Review required
12 — Dyness Tower official product page (dyness.com), technical specification table 'Expansion' row and feature text 'Up to 12 clusters in parallel, 7.1kWh~255.72kWh capacity'
4 — Dyness Tower datasheet-EN V1.0-20230704, 'Parallel Expansion' row: 'Max. 4 towers can be connected in parallel' (distributor mirror: estsolar.lt)
Additional documented parameters
Recorded verbatim from the source; no schema field exists for these yet.
| Battery system charge current [A] (standard) | 7.4 A |
| Battery system charge voltage (V/DC) | 657.0 V |
| Battery system discharge current [A] (standard) | 7.4 A |
| Battery system discharge minimum voltage (V/DC) | 504 V |
| Battery system max charge & discharge current [A] (in communication with inverter) | 22.5 A |
| Colour (official product page) | White |
| Longest storage duration without charge/discharge (user manual) | should not exceed 6 months; activation every three months advised |
| Market experience claim (official product page) | 'It has been market-verified for 5 years with 0 accidents.' |
| Max depth of discharge | 100% |
| Module configuration | 6 series |
| Pre-storage SOC (user manual storage chapter) | 50 - 55% |
| Short circuit current [kA] | 1.5 kA |
| documented_relationship:battery_inverter | {"to_manufacturer": "Afore", "to_model": "AF3K~9.6K-DH, AF3K~30K-TH", "relationship_type": "battery_inverter", "match_level": "series", "communication_protocol": "CAN/RS485 (Tower BDU EXT-CAN/RS485 RJ45 port)", "required_settings": "UNKNOWN - the compatibility list carries no protocol/DIP/firmware column, and the Tower user manual only says to select the correct battery type in the inverter settings", "source": "List of the Inverter Brands Compatible with Dyness Tower Series, last updated 06/05/2025 (distributor mirror: vanmeenen.com)", "source_url": "https://www.vanmeenen.com/wp-content/uploads/2025/05/Dyness-Tower-series-campatible-list-250506.pdf", "source_page": "compatibility table", "confidence": "distributor-verified", "notes": "The document's Tower columns are headed T-7 / T-10 / T-14 / T-17 / T-21 and every listed brand is check-marked across all five columns, so the approval is |
| identity.product_status | current |
| manufacturer_legal_entity_as_printed | Dyness Digital Energy Technology Co., LTD |