Schneider Electric EZ9F51310 Easy9 3P 10 A C-curve MCB

EZ9F51310: Easy9 3P 10 A C-curve miniature circuit breaker

The EZ9F51310 is a Schneider Electric Easy9 miniature circuit breaker with three-pole construction, a 10 A rated current and a C trip curve. It uses thermal-magnetic tripping, clips onto a DIN rail and is rated for AC networks. Seven Star LLC supplies the EZ9F51310 in Oman and the GCC as an independent supplier based in Muscat.

Reading the reference from the product title: 3P is the pole count, 10 A is the rated current [In], C is the curve code, and the series title states the breaking capacity and voltage class. Three protected poles open all three phases at once, so a fault on one phase disconnects the whole three-phase load. This sits in the higher breaking-capacity group of the series, with 10000 A listed at both 230 V and 400 V.

What the C curve and 10 A rating mean for the EZ9F51310

The datasheet gives a magnetic tripping limit of 5 to 10 times In. For a 10 A device that works out to roughly 50 A to 100 A, the band in which the instantaneous magnetic element is expected to open the circuit on a short circuit. Below that, the thermal element handles ordinary overloads and trips more slowly the smaller the overload is. The C characteristic tolerates the inrush of lamps, small transformers and motors better than a B curve, yet reacts sooner than a D curve to a genuine fault.

Under IEC 60898-1, the standard named in the datasheet, a breaker of this kind carries its rated current without tripping and then opens within defined times at higher multiples; the exact time-current curve belongs to the manufacturer’s published characteristics. This unit is therefore best matched to lighting circuits, small control supplies and low-power equipment feeders, where the cable is sized for 10 A or slightly above and the downstream load has moderate starting current.

Technical specifications of the EZ9F51310

Installation and maintenance of the EZ9F51310

Isolate the board before work, clip the EZ9F51310 onto the DIN rail and make sure the toggle moves freely. Strip conductors to the length the terminal needs, insert them fully and tighten to 2 N.m. This unit accepts the cross-sections listed above, so avoid forcing larger cable or using ferrules that do not fit. After energising, operate the toggle once to check the contact position indicator, then label the circuit.

Periodically re-torque terminals in boards that see vibration or large temperature swings, and look for discoloured plastic, which indicates heat at a termination. A breaker that has tripped on a short circuit should be investigated before it is reset, and one that trips repeatedly on a normal load points to an undersized rating, not a faulty device.

Size, terminals and mounting of the EZ9F51310

The EZ9F51310 is 54 mm wide, 81 mm high and 66.5 mm deep, which equals 6 modules of 9 mm. It clips on a DIN rail and its toggle shows the contact position. Terminals are tunnel type, top or bottom, with Tunnel type terminal (top or bottom) 1–25 mm² rigid; Tunnel type terminal (top or bottom) 1–16 mm² flexible. The tightening torque is 2 N.m, and a calibrated screwdriver avoids both loose and crushed conductors.

At 6 modules it takes three times the width of a single-pole breaker, so allow for the extra rail length and neutral busbar arrangement. Ambient limits are -5 to 60 °C in operation and IP20 applies to the front of the breaker, so the enclosure supplies the wider protection.

Breaking capacity and voltage data of the EZ9F51310

Breaking capacity is listed as 10000 A Icn at 230 V AC 50/60 Hz; 10000 A Icn at 400 V AC 50/60 Hz. The rated operational voltage is 400 V AC and the rated service breaking capacity [Ics] is 10 kA 100 % x Icn at 400 V AC 50/60 Hz. The Ics line is expressed as a percentage of Icn, so read both figures together when you compare with the prospective short-circuit current at the board.

The prospective fault current at the installation point must stay below the relevant rating, and the voltage on your network must match the voltages the datasheet quotes, not only the nominal value. The datasheet also lists 500 V AC insulation voltage and a 4 kV impulse withstand voltage. For a 3P circuit, confirm the supply type (phase-neutral or phase-phase) before ordering, because the quoted voltage differs between the references in this group.

How the EZ9F51310 compares with sibling references

These nearby Easy9 C-curve references from the same group show how rating, width and trip band move together. The pole count and the breaking-capacity group are the real differences; the amp rating changes the magnetic range and, at the top end, the terminal torque.

Information to send with an RFQ for the EZ9F51310

• Exact reference EZ9F51310 and the quantity needed.
• Supply voltage, system type and earthing arrangement.
• Prospective short-circuit current at the board, if known.
• Load description and cable size for the circuit.
• Any companion devices needed in the same order, such as other pole counts or ratings.
• Delivery location and project timeline.

Documents and quotation

The manufacturer datasheet for the EZ9F51310 is attached on this page and holds the full specification summarised above.

Send us the reference EZ9F51310, quantity and delivery location and Seven Star LLC will reply to your request. We supply as an independent supplier based in Muscat.