Fox ESS EQM2900 2.88kWh Master Battery

Fox ESS EQM2900 2.88kWh master battery

The Fox ESS EQM2900 is the master battery module for the EQ2900 high-voltage storage system. It acts as the main battery in the stack and is required where the installation needs the master unit rather than an expansion battery. For customers or installers familiar with older part codes, EQM2900 is the updated replacement for ECM2900 references still found on legacy paperwork, historic stock files or earlier installations.

This matters because many buyers still search using older ECM product codes. Making the replacement clear helps avoid confusion while keeping the product page aligned with the current Fox ESS naming. It is also important to note that the latest EQM2900 modules use Type A connectors, so existing systems should always be checked before ordering replacement or expansion parts.

What EQM2900 is used for

EQM2900 is used when building or replacing the master section of a Fox ESS EQ2900 battery stack. It is not the add-on battery for increasing capacity later, but the core module that starts the system. Additional storage is then added with matching EQS2900 support batteries.

This makes it suitable for new Fox ESS battery installations, replacement projects and system expansions where the original master battery reference has changed from ECM2900 to EQM2900. It is particularly useful where a modular high-voltage battery system is preferred over a fixed-capacity setup.

Main features

• 2.88kWh nominal capacity
• Master battery for the EQ2900 range
• 90% depth of discharge
• CAN communication
• Scalable battery system up to 20.16kWh
• Supplied in Type A connector format

The 2.88kWh capacity makes this a practical starting point for modular storage systems where the customer may want to increase battery capacity later. Rather than oversizing the system from the outset, the EQ2900 platform allows projects to start smaller and expand as energy usage, tariff strategy or storage demands change.

Fox ESS also quotes 90% depth of discharge, helping deliver strong usable energy from the installed battery capacity. Combined with CAN communication and the wider modular design of the EQ range, that gives installers a flexible battery platform for compatible Fox ESS systems.

Master and slave battery difference

One of the most important points on this product is that EQM2900 is the master battery, not the slave or support battery. If a customer is starting a new EQ2900 stack or replacing the master module, this is the correct unit. If they are only expanding capacity on an existing compatible stack, they would normally need the EQS2900 instead.

That distinction is worth making clearly because it helps reduce incorrect orders and makes the battery roles easier to understand at a glance.

Installation and compatibility notes

Fox ESS presents the EQ battery system as a plug-and-play storage solution, which helps simplify installation for qualified professionals. The range is designed for scalable battery storage projects and can be used in suitable indoor or outdoor stand-mounted applications, subject to correct system design and installation requirements.

Before ordering, installers should check compatibility carefully, especially where an older system is being expanded or updated. Current EQM2900 modules use Type A connectors, while older ECM or ECS versions may differ. That makes connector verification essential before mixing old and new components in one stack.

Replacement for older ECM2900 references

If you have reached this page while searching for ECM2900, this is the updated model you are likely looking for. EQM2900 is the current Fox ESS replacement reference for the older 2.88kWh master battery code, helping customers and installers move onto the latest product naming without losing track of what fits the system.

For ecommerce and trade supply, this is useful because many repeat buyers still search by the older code they already know. Making the replacement clear improves product search visibility and gives buyers more confidence that they are ordering the current equivalent part.

Why buy Fox ESS EQM2900 from Evergy

At Evergy, we understand that battery system compatibility matters just as much as the headline specification. The Fox ESS EQM2900 is a straightforward choice for projects needing the current 2.88kWh master battery within the EQ high-voltage range, whether for a new installation, a replacement requirement or a carefully checked system upgrade.

It is a sensible option for buyers who want a modular Fox ESS battery system, a current-production replacement for ECM2900, and a clear route for future expansion using matching EQS2900 modules.

Related ranges

You can also browse our wider solar batteries range or view more products from Fox ESS to compare compatible storage options.

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