The S800 bridges the gap between a miniature circuit breaker and a moulded case breaker: DIN-rail mounted, up to 125 A, with breaking capacities well beyond a standard MCB. The C, N, S and P classes step up in performance, making the range a common choice for main incomers on sub-boards and for protecting large motor and transformer feeders.
The class letter (C, N, S, P) is the breaking-capacity tier — choose it from the installation's fault level.
Confirm the curve; the range covers B, C, D and K characteristics across the ratings.
At 100–125 A the terminal and cable arrangement matters — check the connection kit needed.
Auxiliary contacts, shunt releases and undervoltage releases are separate accessories.
Frequently asked questions
S800 or a moulded case circuit breaker?
The S800 gives MCCB-level breaking capacity on a DIN rail up to 125 A, which saves board space and cost. Above that current, or where adjustable electronic protection and discrimination are needed, a moulded case breaker such as the Tmax XT is the right device.
What is the difference between S800N and S800S?
Breaking capacity class. S800S interrupts a higher prospective fault current than S800N at the same rating and footprint. Choose from the board's calculated fault level, not by preference.
Are S800 breakers suitable for DC?
Specific DC-rated versions exist within the wider S800 family; a standard AC device should not be used on DC.