Schneider Electric A9C20731 iCT 25 A 1NO 230-240 V Contactor

A9C20731: single-pole 25 A contactor in an 18 mm module

The A9C20731 is a Schneider Electric Acti9 contactor listed in the datasheet as: iCT 25A 1NO 230 to 240V 50Hz contactor. The A9C20731 is the smallest building block of the Acti9 iCT contactor range: one normally open pole, a 230 to 240 V AC coil and a body only two 9 mm pitches wide. It exists to let a small control signal, such as a time switch, a thermostat or a push-button, switch a single-phase load of up to 25 A without that load having to pass through the control device itself. Seven Star LLC supplies the A9C20731 in Oman and the GCC as an independent supplier based in Muscat.

Reading the reference from the datasheet: A9C is the Acti9 contactor family code, the description gives 25 A, one pole with one normally open contact (1P, 1 NO) and a coil of 230 to 240 V AC at 50 Hz. The datasheet states a rated operational voltage of 250 V AC, so this is a single-phase device (phase switched, neutral not interrupted) and not a three-phase motor contactor.

Technical specifications of the A9C20731

Power circuit and coil data of the A9C20731

The rated operational current is 25 A AC-7A; 8.5 A AC-7B. Rated operational voltage: 250 V AC 50 Hz. Maximum power figure: 1.2 W at 250 V AC. Coil voltage: 230 to 240 V AC 50 Hz. Hold-in consumption: 2.7 VA. Inrush consumption: 9.2 VA. Rated insulation voltage: 500 V AC 50/60 Hz. Rated impulse withstand voltage: 4 kV. Mechanical durability: 1000000 cycles.

Because it has a single pole, the A9C20731 interrupts only the phase conductor of a circuit. That is acceptable for many lighting and resistive heating circuits where local rules allow single-pole switching, but the designer must confirm that the installation practice at the site accepts a neutral that stays connected when the contactor is open. Where a double-pole break is required, the sibling A9C20732 with two poles is the natural step up in the same 18 mm width.

AC-7A and AC-7B ratings of the A9C20731: reading the load categories

The datasheet lists the load ratings by category from IEC/EN 61095. AC-7A covers slightly inductive loads of household and similar use, which is where lighting, heating and resistive circuits belong. AC-7B is the rating for the motor loads of household appliances and is always much lower than the AC-7A figure. A designer who reads only the headline current can therefore overload the contacts with a motor-type load; reading the category avoids that.

Electrical durability in the datasheet: 100000 cycles IEC/EN 61095 25 A 50 Hz AC-7A; 30000 cycles IEC/EN 61095 8.5 A 50 Hz AC-7B; 30000 cycles IEC/EN 61095 50 Hz AC-7C.

How the A9C20731 compares with neighbouring iCT contactors

The A9C20732 differs in poles 2P against 1P here; contacts 2 NO against 1 NO here. The A9C20834 differs in poles 4P against 1P here; contacts 4 NO against 1 NO here; coil 220 to 240 V AC 50 Hz against 230 to 240 V AC 50 Hz here; width 36 mm against 18 mm here.

The table below lists the iCT references of this group with their main differences so that a purchase order can be checked against the family.

Selection checklist for the A9C20731

• Confirm that one switched pole is acceptable for the circuit and the local wiring practice; otherwise select a two-pole version.
• Check that the load current, including lamp inrush for lighting groups, stays within the 25 A AC-7A rating and the 8.5 A AC-7B motor-type rating.
• Match coil voltage and frequency to the control supply; this reference uses 230 to 240 V AC 50 Hz.
• Check the width of 18 mm (2 pitches) against free rail space and spare gaps for heat.
• Confirm the number of operations per day stays within the datasheet figure.

Mounting, wiring and maintenance of the A9C20731

Mount the contactor on a 35 mm DIN rail by clipping it on; no screws are needed for the body. Use the tightening torques from the datasheet: Control circuit: 0.8 N.m, Power circuit: 0.8 N.m. Leave a gap beside the contactor when several are fitted in a row, because every energised coil dissipates heat, and in a warm Gulf plant room the margin to the -5 to 60 °C operating limit is often small. Label the coil terminals A1 and A2 clearly, since a mistaken coil connection is the most common commissioning error.

The datasheet lists the environment as -5 to 60 °C in operation and -40 to 70 °C in storage, relative humidity of 95 % at 55 °C, an altitude limit of 2000 m and pollution degree 2.

Where the A9C20731 is used in Oman and the GCC

In Oman and the GCC a one-pole 25 A contactor is typical of villa and small commercial distribution boards: it switches an outdoor lighting circuit from a photocell or time switch, a single-phase water heater element or a ventilation fan group. The datasheet places the product in the residential and small-commercial market segments, which matches this use.

Heat inside a distribution board is the practical enemy. The datasheet gives -5 to 60 degrees C for operation, so a board in a sun-exposed plant room should be checked on site; leaving a spare module width beside the contactor helps it shed heat. Only 1.2 W is listed at 250 V AC for the pole, so the heat contribution is small, but several contactors side by side add up.

Information to send with an RFQ for the A9C20731

• Full reference (A9C20731) and quantity required
• Supply and control voltage at site, with the frequency
• Existing panel, rail and neighbouring devices it must fit beside
• Delivery location and timing
• Whether it is a spare, a like-for-like replacement or a new installation
• Load type and current: lighting, heating or motor-type

Documents and quotation

A datasheet for the A9C20731 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.