Schneider Electric A9N61521 C60H-DC 2P 1 A C Curve

A9N61521: C60H-DC 2P 1 A C-curve breaker

The A9N61521 is a Schneider Electric Acti9 C60H-DC miniature circuit-breaker with 2 protected poles, a rated current of 1 A and a C trip curve. Although the shop title only says miniature circuit breaker, the datasheet lists the network type as DC, so this is a direct-current device and should not be confused with the AC members of the Acti9 range. Seven Star LLC supplies the A9N61521 in Oman and the GCC as an independent supplier based in Muscat.

Reading the reference from the datasheet rather than from the number itself: A9N61521 is the 1 A step in the 2-pole ladder, it is rated for 500 V DC, and it occupies 4 modules of 9 mm on the DIN rail. Two poles switch both conductors of the circuit together, which is why this version carries the higher rated voltage.

2P versus 1P in the C60H-DC family

Within the two-pole ladder the available current steps in our lane are 1, 2, 3, 4, 5, 6, 10, 16, 20, 25, 32, 63 A. A9N61521 shares the 500 V DC rating, 4-module width and 0.256 kg weight with all of them; only the current rating changes. Siblings: A9N61522 (2 A), A9N61523 (3 A), A9N61524 (4 A), A9N61525 (5 A), A9N61526 (6 A), A9N61528 (10 A), A9N61531 (16 A), A9N61532 (20 A), A9N61533 (25 A), A9N61535 (32 A), A9N61539 (63 A).

The single-pole references (A9N61508 (10 A), A9N61511 (16 A), A9N61512 (20 A), A9N61519 (63 A)) are rated 250 V DC, occupy 2 modules and weigh 0.128 kg. They are the better fit for lower-voltage buses where a single pole is accepted, while the 2P series covers the higher 440 V DC and 500 V DC systems and interrupts both conductors.

Typical use of the A9N61521 in Oman and the GCC

DC distribution appears in the region in substations, power plants, telecom shelters, solar-powered monitoring stations, battery rooms and process control cabinets in oil and gas, petrochemical and desalination facilities. A low-current branch like this one, rated 1 A, is usually found on instrument and signalling feeders inside marshalling cabinets. The datasheet gives an operating range of -25 to 70 °C, tropicalisation level 2, pollution degree 3 and altitude up to 2000 m, which is a useful starting point for panels in hot, dusty, humid coastal sites; keep panels out of direct sun.

Technical specifications of the A9N61521

How a thermal-magnetic DC breaker protects the circuit

The A9N61521 uses a thermal-magnetic trip unit. The thermal element reacts to a sustained overload by bending as the conductor heats, giving a delayed trip that tolerates short switching surges. The magnetic element reacts to a short circuit almost instantly. The curve code on the datasheet is C, which places the instantaneous threshold higher than a B curve and suits loads with moderate inrush.

Interrupting direct current is harder than interrupting alternating current because there is no natural current zero to help extinguish the arc. That is the reason the datasheet gives breaking capacity separately for each DC voltage: 20 kA at 220 V DC and 250 V DC, 10 kA at 440 V DC and 6 kA at 500 V DC. Service capacity Ics, at 75 % of those values, is 15 kA at 220 V DC and 250 V DC, 7.5 kA at 440 V DC and 4.5 kA at 500 V DC. The lower the system voltage, the higher the fault current the device can clear, so always compare the prospective fault current at your actual bus voltage with the matching line, not with the largest number.

Installation, commissioning and maintenance of the A9N61521

The A9N61521 clips onto a 35 mm symmetrical DIN rail and is fixed mounting. The power terminals, top or bottom, accept a tightening torque of 2.5 N.m; use a calibrated driver rather than judgement, because DC contacts that are under-tightened heat up and can degrade slowly. The datasheet lists comb busbar compatibility at top or bottom in standard configuration, which allows neat feeder groups in a distribution board.

At commissioning, verify polarity against the wiring diagram, operate the toggle several times, confirm that the contact position indicator and the ON/OFF indication agree with the actual state, and check that the padlocking provision in position O works with your lock-out procedure. Mechanical durability is stated as 20000 cycles and electrical durability as 3000 cycles at L/R = 2 ms, so an annual operation check is reasonable, but do not use the breaker as a routine switch for heavy inductive loads.

Selecting the A9N61521 for your DC circuit

At 1 A this is the smallest step, suited to signalling loops, meter feeds and electronic inputs where the load current is a fraction of an ampere and the cable is very light. A 1 A rating is typically chosen for control supplies, signalling, instrumentation feeders and small auxiliary loads where conductors are thin. At this level the breaker’s job is mostly to protect the cable and to give a clear isolation point, so the conductor size and the load’s inrush matter more than the breaking capacity. Check that a 1 A to 6 A step truly leaves headroom above the running current, because thermal tripping at 25 °C reference conditions can come sooner in a hot panel. This is the first step of the 2-pole ladder in our lane; the next rating up is A9N61522 at 2 A.

• Highest system voltage: must not exceed 500 V DC.
• Prospective short-circuit current at the breaker location, compared with the Icu line for that voltage.
• Continuous load current and ambient temperature inside the enclosure.
• Number of poles needed: 2 here; confirm whether your earthing arrangement needs both conductors switched.
• Polarity or terminal markings: follow the marks on the device and the wiring diagram supplied with the installation.

What to send with an RFQ for the A9N61521

To quote the A9N61521 quickly, send the complete part number, the quantity, the system DC voltage and earthing arrangement, the highest prospective fault current, whether you need 2 poles, and the delivery location in Oman or the GCC. Mention if it replaces an existing device so we can compare labels.

Documents and quotation

A datasheet for the A9N61521 is attached on this page. The copy we reviewed is dated 8 Nov 2026 and lists the environmental data of the reference as well as the electrical values above.

Send the part number and your project details through the RFQ form; Seven Star LLC will confirm availability and lead time in Oman and the GCC.