MERC optimiser

Huawei MERC-1100W-P and MERC-1300W-P are DC module controllers for named commercial SUN2000 inverter families. They are not inverters, and the power in each model name describes DC power handled by the optimiser.

Controller and module input limits

The two codes have different input-power ceilings, so the larger nameplate cannot be treated as a software setting on the smaller controller. Module voltage and current must remain inside every input limit in the specification, including the MPPT range and short-circuit-current ceiling.

The efficiency figures describe the controller under specified conditions rather than the energy yield of the full array. The stated shutdown voltage applies to each optimiser separately.

Huawei gives each MERC code a separate module-STC power ceiling.

Full-optimiser design

Huawei states that MERC-1100/1300W-P supports full-optimiser configuration only. The current table lists compatible M2, M3, M5 and 50KTL-M3 inverter families, with minimum and maximum optimiser counts per string that vary by inverter.

MERC must not be mixed with SUN2000-450W-P2, SUN2000-600W-P or SUN2000-600W-PA0 under the same controller.

Huawei describes possible protective shutdown in the upper part of the operating-temperature range, so its maximum ambient figure is not an unrestricted full-power rating.

MERC warranty record and UK supply status

Huawei’s European policy dated 19 May 2026 places MERC-1100/1300W-P in its optimiser warranty schedule while leaving the sales contract controlling. MERC remains in Huawei’s commercial product material, although current UK supply for each code is unconfirmed. Compatibility must come from the current inverter table.

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