Schneider Electric A9E21180 Acti9 iRCP Phase Control Relay 400 V

A9E21180 iRCP phase control relay: protection against phase loss and reversal

The A9E21180 is a Schneider Electric Acti9 iRCP phase control relay for a 400 V, 50/60 Hz three-phase supply, listed in the datasheet with one changeover signal contact (1 C/O). It monitors the three phases and signals if one is lost, if the phase order is reversed or if the phases are unbalanced beyond the set threshold. Seven Star LLC supplies the A9E21180 in Oman and the GCC as an independent supplier based in Muscat.

The relay does not carry the motor current. It watches the supply and its changeover contact is wired into the control circuit of a contactor, a circuit breaker shunt trip or an alarm, so that the load is stopped or the operator is warned before damage occurs. A reversed phase sequence is a threat for pumps, fans, compressors and conveyors that must turn in one direction only.

Technical specifications of the A9E21180

Settings and detection data for the A9E21180

The tripping threshold is adjustable from 5 to 25 percent of phase asymmetry with a rotary knob on the front, and the measurement range is selected by wiring. The datasheet lists a hysteresis of 5 percent, a time delay entry of 0.3 s and an accuracy error of plus or minus 10 percent. These figures explain how the relay behaves: it needs a deliberate imbalance to react, it releases only after the supply has recovered by the hysteresis amount, and the knob position should be seen as a setting with a tolerance rather than a precision measurement.

The supply is 400 V AC 50/60 Hz and the relay consumes 3 VA. The contact is rated 8 A at 250 V AC with a power factor of 1, so it is a signal contact for control circuits and small coils and not a load-switching device.

Front indications and diagnostics of the A9E21180

Two LEDs are fitted. A green LED shows that the relay has power, and a red LED indicates a fault; the datasheet states that it reports phase loss or reversal. This gives a technician an immediate first diagnosis at the board: green without red means the supply is within the thresholds, green with red points to the supply, and no green points to the relay’s own supply or wiring.

A practical test is to compare the indication with a voltage measurement at the supply terminals, then swap two phases temporarily with the load isolated to confirm that the reversal detection works. Such a test should be done by qualified staff and recorded in the commissioning sheet.

Wiring and mounting of the A9E21180

The A9E21180 clips onto a 35 mm DIN rail, occupies four 9 mm pitches (36 mm) and measures 88.1 mm in height and 67 mm in depth, with a net weight of 0.21 kg. Terminals are tunnel type and accept up to six rigid conductors of 1.5 mm squared on the top or bottom. That number of terminals allows the three phases and neutral if needed, together with the changeover contact outputs, without extra bridging.

The operating ambient range is -5 to 55 °C and the storage range is -40 to 80 °C. The lower operating limit of -5 degrees C is irrelevant in the Gulf, but the upper limit of 55 degrees C needs checking in plant rooms. IP20 protection means the relay must sit inside a closed enclosure.

Where the A9E21180 fits in a motor or pump circuit

In a typical scheme the supply passes through a circuit breaker to the phase relay and the contactor. The changeover contact of the relay is wired in series with the contactor coil so that a fault removes the coil supply and drops the contactor. A second contact path can drive an alarm lamp or a signal to the building management system, using the changeover contact in its other state.

Because the relay watches asymmetry as well as loss and reversal, it also protects against a gradual voltage imbalance, which can overheat a motor even when all three phases are present. For critical motors the thermal protection and a motor protection relay remain necessary; the phase control relay is the first line of defence at the supply side, not a replacement.

Applications of the A9E21180 in Oman and the GCC

In Oman, phase loss events appear on long overhead feeders, at construction sites on temporary supplies and in buildings that move between mains and generator supply. A phase relay protects air-conditioning compressors, water pumps, lifts and escalators, all of which can be damaged by a lost phase or a wrong rotation after maintenance on the supply.

Another typical use is at generator changeover panels and in temporary site distribution, where the phase order can change when connections are remade. A phase sequence relay at the incomer prevents the plant from starting in reverse when a cable is reconnected incorrectly.

Selection checklist for the A9E21180

• Supply: 400 V AC three-phase, 50/60 Hz
• Asymmetry threshold: adjustable 5 to 25 percent, with 5 percent hysteresis
• Output: one changeover contact, 8 A at 250 V AC, for control duty only
• Space: four 9 mm pitches, 36 mm wide
• Environment: -5 to 55 degrees C in operation, IP20, closed enclosure

Information to send with an RFQ for the A9E21180

• Reference (A9E21180) and quantity
• Supply voltage, frequency and neutral availability
• Load protected: motor, pump, compressor or lift
• How the output is used: contactor coil, shunt trip or alarm
• Delivery location and timing

Documents and quotation

A datasheet for the A9E21180 is attached on this page. It lists the electrical, mechanical and environmental data summarised above, and it should be read together with the manufacturer’s installation instructions for the final design.

Send us the part number, quantity and application and we will confirm availability and a quotation. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.