# 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](https://github.com/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.