COM connector

Missing Communication Connector for Huawei LUNA2000-5KW-C0 – Matching Weidmüller Part Found

After buying a Huawei LUNA2000 battery system at a bankruptcy auction, I discovered that the communication connector for the LUNA2000-5KW-C0 top module was missing. This connector is needed for the low-voltage communication wiring between the Huawei inverter and the battery control module.

After comparing the connector housing, pitch, number of positions and mechanical fit, I found what appears to be the matching connector:

Weidmüller 1277310000
DigiKey part number: 281-8087-ND

The connector is a 10-position pluggable terminal block with 3.50 mm pitch. It is listed by DigiKey part number 281-8087-ND as a Weidmüller terminal block plug, manufacturer part number 1277310000.

I have physically tested this connector in the Huawei LUNA2000-5KW-C0 communication port and it fits mechanically. This article identifies the connector only and is not a wiring guide.

Background

The Huawei LUNA2000-5KW-C0 is the top control/power module used with the LUNA2000 battery modules. When these systems are bought second-hand, from surplus stock or from bankruptcy auctions, it is quite common that small accessories are missing. In my case, the battery module itself was present, but the removable communication plug was not included.

Without this plug, it is difficult to make a clean and serviceable connection to the communication port. The power connectors are a separate issue that I post in a separate article; this article is only about the small communication terminal plug.

Identified Connector

The connector I found is:

• Manufacturer: Weidmüller
• Manufacturer part number: 1277310000
• DigiKey part number: 281-8087-ND
• Type: Pluggable terminal block plug
• Number of positions: 10
• Pitch: 3.50 mm / Row pitch: 2.50 mm
• Connection style: Push-in spring terminal
• Orientation: Inline / 180°

This connector matches the missing plug for the communication connector on my Huawei LUNA2000-5KW-C0 top module.

Photos

Below are some photos of the connector and the LUNA2000-5KW-C0 communication port.

LUNA2000-5KW-C0 communication port without connector

Weidmüller connector plug 1277310000

[Insert photo: connector installed in the LUNA2000-5KW-C0 top module]

Important Notes Before Wiring

This article is only intended to help identify the missing physical connector. It is not a complete wiring guide.

Before connecting anything, make sure that you have the correct Huawei installation manual for your exact inverter and battery model. You should also verify the pinout, cable type, shielding and grounding requirements from the official documentation.

Do not assume that the connector position alone is enough to determine the wiring. Incorrect wiring of communication, enable, ground or shield connections may prevent the battery from working and could potentially damage equipment.

The LUNA2000 system is part of a high-voltage battery installation. Installation and commissioning should be carried out by a qualified person familiar with Huawei ESS systems and local electrical regulations.

Why This May Be Useful

If you buy a used Huawei LUNA2000 battery, especially from an auction, the small removable plugs may be missing. These parts are easy to overlook, but without them the system can be difficult to install properly.

Hopefully this part number helps someone else avoid the same search.

For my unit, the matching communication connector was:

Weidmüller 1277310000
DigiKey 281-8087-ND

As always with second-hand solar and battery equipment: verify everything carefully before powering the system.