Replacement batteries for three-phase UPS systems

What you are actually replacing

Small single-phase units take a cartridge. Three-phase systems take a string: a series of blocks or modules wired to a DC bus, held in a cabinet or on a rack. The UPS model tells you the bus voltage and how many blocks sit in the string, and the part number on an existing block tells you the format. Replace a string as a set, not a block at a time, because a new block sitting in an aged string ages to match it.

What we need to identify it

• UPS make and model, from the plate on the front or side
• The part number printed on the block, module or cartridge already installed
• String voltage, and how many blocks or modules the cabinet holds
• Whether the batteries sit inside the UPS, in a matched cabinet, or on an open rack
• How old the current string is, if you know

Signs a string is due

• The UPS reports a failed or aborted self test
• Measured runtime is well short of what the system is rated to hold
• Impedance readings have drifted apart across the string
• A block is swollen, leaking, or running hot compared to its neighbours
• The string is past the service life the manufacturer states for its design

By manufacturer

Go to the brand page for model level detail, or send us the model and we will identify the string.

Single-phase and small systems

If the unit is single-phase or rack mount, the cartridge is usually a stock item, listed in the replacement battery catalogue.

Send us the details

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