Schneider Electric 28900 INS40 3P 40 A Switch Disconnector

28900: ComPact INS40 3-pole switch disconnector, 40 A

The 28900 is the ComPact INS40, a 3-pole switch disconnector rated 40 A. The datasheet lists a rotary handle in black, fixed mounting on DIN rail or plate, front connections top and bottom and a contact position indicator. Suitability for isolation is Yes. Seven Star LLC supplies the 28900 in Oman and the GCC as an independent supplier based in Muscat.

The ComPact INS family is a load-break isolator, not a circuit breaker: it has no trip unit and gives no protection of its own, so it is used with a breaker or fuse upstream. The 3-pole version is the right match for a three-phase motor feeder without neutral, such as a pump or fan starter, or the local isolator beside a compressor or conveyor drive.

What the 28900 ratings mean in practice

The datasheet gives the AC-22A rated current at 380 to 415 V as 40 A, and the same value at 220 to 240 V and 440 to 480 V. At 500 V in utilisation category AC-23A the figure is lower, 32 A, which is worth remembering for motor feeders on a 500 V system. The conventional free-air thermal current is 40 A at 60 °C.

The making capacity is 15 kA switch-disconnector alone 500 V AC at 50/60 Hz; 75 kA with upstream protection circuit breaker 500 V AC at 50/60 Hz. The second figure only applies when the switch is protected by an upstream circuit breaker, so the fault study of the board should confirm that the protective device is the one assumed. Short-time withstand values are listed from 0.55 kA for 30 s up to 3 kA for 1 s.

For motors in AC-23 the maximum power is 11 kW at 220 to 240 V, 20 kW at 380 to 415 V, 22 kW at 440 V and 18.5 kW at 500 to 525 V. For direct current the datasheet lists 125 V DC with two poles in series, which means the poles must be wired in series as stated, otherwise the DC rating does not apply.

28900 technical specifications

Information to send with an RFQ for the 28900

Please include the quantity, the supply voltage, the load and the enclosure type. If the 28900 replaces a unit in service, a photograph of the old nameplate helps us confirm the match.

• Part number 28900 and quantity.
• System voltage, frequency and number of poles needed.
• Upstream protective device and prospective fault current.
• Delivery location and required date.

Selection checklist for the 28900

• Number of poles: 3, and whether the neutral must be switched.
• Load current against 40 A at the system voltage.
• Voltage: up to 500 V AC, or 125 V DC with two poles in series.
• Fault level at the board and the upstream breaker that supports the 75 kA making figure.
• Visible break requirement of your site procedure.
• Mounting: DIN rail or plate, and the handle position in the enclosure door.

Environment and installation of the 28900 in Oman and the GCC

The listed operating ambient is -25 to 70 °C with pollution degree 3. For Gulf installations the key check is the temperature inside the board, which can be far above the outdoor figure in summer. Dust and humidity rule out leaving the 28900 in an open or unventilated position, and a lockable enclosure with filtered ventilation is the norm in plant rooms, substations and pump stations.

Typical uses are local isolators for motors in water treatment and desalination, plant isolation in oil and gas auxiliaries, and the supply isolator of a distribution board in a commercial or industrial building.

Mounting and connecting the 28900

The 28900 mounts on DIN rail or on a plate, with front connections at both ends and a 18 mm connection pitch. The cable cross section is 1.5 to 50 mm² and the net weight is 0.5 kg. The housing carries IP40 protection with IK07 impact rating, so it is intended for use inside a board and not in an open yard.

The datasheet marks visible break as No. If your site procedure demands a visible isolation gap, as some utilities and plant standards do, the 28900 relies on the handle position indicator instead, and you should check that this meets the lock-out rules before specifying it.

28900 compared with its INS neighbour 28903

The two ComPact INS references in this group differ in pole count, current rating and DC voltage option. The comparison below uses only datasheet values.

Documents and quotation

The manufacturer datasheet for this reference is attached on this page, so you can compare the figures quoted here with the original before you commit to a design or a purchase order.

To proceed, send the part number, the quantity and a few lines about the installation and we will reply with availability and a quotation. Seven Star LLC works as an independent supplier in Muscat with no affiliation to the manufacturer.