DUoS Tariff ID

Under MHHS, the single legacy LLFC concept separates into two distinct identifiers:

• DUoS Tariff ID - determines which distribution (DUoS) tariff category applies, that is, your charges
• LLF ID - determines which line loss factors apply for settlement, that is, your losses

Historically both jobs were bundled into one 3-character LLFC. MHHS pulls them apart so charging and loss-adjustment can be referenced independently.

The crucial continuity point: At MHHS go-live the DUoS Tariff ID is identical to the existing LLFC (the same data item, J0147, simply renamed over time). It is a 3-character code in the same format and it maps to the same 32 CDCM tariff categories. So existing charge lookups keyed on the LLFC continue to work unchanged; only the name of the field evolves.

Where each one lives: The split is in the settlement data model, not on the supply number itself. The 22-digit MPAN top line carries the DUoS Tariff ID; the LLF ID is held in settlement data, not displayed on the MPAN.

Why split it at all: Separating charging from losses gives a cleaner data model for a half-hourly-settled market, where loss factors are applied per settlement period. The LLF ID can be maintained and updated independently of the charging tariff.

The practical read: If you maintain systems, treat the DUoS Tariff ID as the new name for the charging role of the LLFC, and expect a companion LLF ID for losses. No tariff rate or category changes as a result of the rename.