Time-of-Use (TOU) Controls: V1 vs V2

Solis hybrid inverters expose two independent, non-interacting sets of scheduled charge/discharge controls. SolisConnect maps both, but they cover different register ranges, different slot counts, and different levels of Modbus/SolisCloud parity.

The config flow’s “V2 support” toggle is auto-detected from the inverter’s HMI firmware version (Modbus register 33002, or SolisCloud inverterDetail field hmiVersionAll) whenever that read succeeds: an HMI version at or above 0x4B00 supports V2. Detection silently overrides whatever the installer picked in the form (same pattern as automatic model detection); if the read fails or is unparseable, the form’s choice is left as-is rather than blocking setup.

Summary

	Time-Charging (V1)	Grid Time of Use V2
Enable switch	Read-only — bit 1 of storage-mode register 43110, exposed as binary_sensor.solis_timed_charge_status (see note below; not user-settable on this firmware family)	Per-slot switch.solis_timed_charge_enable_N / switch.solis_timed_discharge_enable_N — bitfield register 43707, one bit per slot
Slot count	3	6
Per-slot fields	Start/end hour+minute for charge and discharge	Start/end hour+minute, target SOC, cut-off voltage, battery current, per slot, for charge and discharge
Charge/discharge current	One global pair (43141/43142), not per-slot	Per-slot (register offset +1 in each slot block)
Target SOC	Not available	Per-slot (register offset +0 in each slot block)
Cut-off voltage	Not available	Per-slot (register offset +2 in each slot block)
Modbus registers	43141-43170	43707-43791
SolisCloud support	Mapped: control CID 103 (see below)	Mapped: control CIDs 5916-5987
SolisCloud enablement gate	N/A	CID 6798 (0xAA55) reports whether the inverter supports V2; SolisConnect reads this once at first poll in cloud-only mode and disables the V2 entities if unsupported (see caveat below)

Time-Charging (V1)

The older scheduling mechanism. One shared charge current and one shared discharge current apply across all slots; only the start/end times vary per slot.

• Enable: bit 1 (Time of Use) of the storage-mode bitfield at register 43110. This bit is read-only in SolisConnect — exposed as binary_sensor.solis_timed_charge_status (sensor_data/binary_sensors.py), not a controllable switch. On this inverter firmware family the bit does not persist as a user-set value: a Modbus write to set it succeeds and is acknowledged, but the device silently clears it again within one poll cycle while leaving every other storage-mode bit untouched. This was confirmed live and cross-referenced against wills106/homeassistant-solax-modbus (plugin_solis_fb00.py), which never exposes this bit as a controllable option either and drives all real TOU enablement through register 43707’s per-slot switches. The Work Mode select (register 43110) likewise now writes only the 8 field-tested whole-register values from that project (1, 17, 33, 37, 41, 49, 64, 96), none of which set bit 1.

• Global settings: Time-Charging Charge Current (43141) and Time-Charging Discharge Current (43142), both in amps, editable as number entities.

• Per slot, each slot is a block of paired hour/minute registers exposed as HA time entities:

  • Charge Start / Charge End

  • Discharge Start / Discharge End

• Register layout: slot 1 starts at 43143, slot 2 at 43153, slot 3 at 43163 (each slot block is 8 registers of data plus a 2-register reserved gap).

• SolisCloud mapping (sensor_data/cloud_mapping.py, control CID 103, “Charge and discharge Settings”): a single comma-separated string of 18 values covering all 3 slots, with per-slot charge/discharge current — unlike Modbus, where current is one pair shared by all slots. Field order per slot: ChargeCurrent, DischargeCurrent, ChargeStart(HH:mm), ChargeEnd(HH:mm), DischargeStart(HH:mm), DischargeEnd(HH:mm). Source: SolisCloud_control_api_command_list workbook, “Hybrid Inverter” sheet.

  • Since Modbus has no per-slot current, decoding a cloud read takes slot 1’s current values as the representative Modbus value, and a Modbus-side current write is broadcast uniformly to all 3 cloud slots. A single-register (current) or paired-register (one time field) write reads the full current 26-register state (from cache, or atRead(cid=103) if the cache is incomplete), splices in the change, and writes the whole recomposed string back — the same pattern already used for TOU V2’s time-pair writes (_execute_tou_time_write, reused here rather than duplicated).

  • Not yet live-verified on a real inverter. The mapping and write path are implemented and unit-tested against the worked example from the CID 103 spec, but several assumptions remain unconfirmed on real hardware: whether CID 103 is supported on non-“Hybrid Inverter” product lines, whether a partial write silently resets untouched fields, and whether broadcasting one Modbus current value to all 3 cloud slots is accepted by the device if it already has genuinely different per-slot currents set. Use the established safe live-write pattern (read original → write test value → verify → revert) before relying on this in production.

• The official Solis RS485_MODBUS Hybrid Inverter protocol document only documents slot 1 (43141-43150); slots 2-3 (43153, 43163) are undocumented in that particular revision but independently confirmed by SolisCloud control CID 103, which covers exactly these 3 slots and no more. (An earlier version of SolisConnect also defined a “Slot 4” and “Slot 5” at 43173-43190; these fell entirely inside the vendor’s documented Reserved range with no confirmation from any source and have been removed.)

Grid Time of Use V2

The newer, richer scheduling mechanism with independent settings per slot.

• Enable: dedicated bitfield register 43707 (Time of Use V2 Switch), 12 bits — one per slot (bits 0-5 for charge slots 1-6, bits 6-11 for discharge slots 1-6). This is a separate switch entity from the V1 enable bit; the two schedules do not share a switch.

• Per slot (1-6), each slot block is 7 registers, base offset 43708 + (slot - 1) * 7 (charge) and 43750 + (slot - 1) * 7 (discharge) — e.g. Slot 1 charge SOC is 43708, Slot 2 charge SOC is 43715:

  • +0: cut-off/target SOC (%, editable number, 0-100)

  • +1: battery current (A, editable number, 0-300, ×0.1)

  • +2: cut-off voltage (V, editable number, 0-300, ×0.1)

  • +3..+6: start hour, start minute, end hour, end minute (paired into a time entity)

• SolisCloud mapping (sensor_data/cloud_mapping.py, _tou_v2_mappings()):

  • Slot enable bits -> CIDs 5916-5927 (charge slots 1-6, then discharge slots 1-6), merged into the shared 43707 bitfield by CloudDataRetrieval._merge_switch_bits. On a cold cache the merged register is only published once all 12 slot-switch CIDs have been observed in a poll cycle, so a CID transiently missing from one atReadBatch response is never mistaken for “off”.

  • Target SOC -> CIDs 5928-5933 (charge), 5965, 5969, 5973, 5977, 5981, 5984 (discharge).

  • Battery current -> CIDs 5948-5963 family (charge), 5967-5986 family (discharge).

  • Cut-off voltage -> the paired CID in the same current/voltage CID families.

  • Start/end time pairs -> CIDs 5946, 5949, 5952, 5955, 5958, 5961 (charge), 5964, 5968, 5972, 5976, 5980, 5987 (discharge); the cloud API represents each pair as a single HH:MM-HH:MM string, which SolisConnect composes from/decomposes into the paired hour/minute registers.

• Enablement gate: SolisCloud CID 6798 reports whether the connected inverter actually supports TOU V2 (value 43605 / 0xAA55 = supported). In cloud-only mode, CloudDataRetrieval reads this once at first poll and — if the value is anything else — disables every sensor covering registers 43707-43791, the same treatment already given to registers with no cloud mapping at all (_disable_unmapped_sensors). A failed or undeterminable read never disables anything (no guessing). This check does not run in dual-protocol modes, since Modbus can still serve these registers there regardless of what the cloud gate reports.

Practical implications

• V1 and V2 are independent schedules on the inverter itself; enabling one does not disable the other, and having both enabled is a device-level conflict outside SolisConnect’s control — check your inverter’s own firmware behavior before enabling both.

• If you only have local Modbus, either scheme is fully readable and writable.

• If you are on SolisCloud-only or a dual-protocol setup where cloud may become active, both V1 and V2 now have cloud mappings; V1’s cloud write path is implemented but not yet live-verified (see above) — prefer V2 for cloud-active setups until V1’s cloud path has had a live test pass.