Schneider Electric CA2KN40M7 TeSys K Relay 4NO 220-230 V AC

CA2KN40M7: four normally open contacts on a 220-230 V coil

The CA2KN40M7 is a Schneider Electric TeSys K control relay listed in the datasheet as: TeSys K control relay – 4 NO – <= 690 V – 220 to 230 V AC coil. A 4 NO contact set is the simplest arrangement: four independent circuits that close together when the coil is energised and open when it drops out. It is the right choice when the relay acts purely as a multiplier of a command, repeating one signal to four separate loads or inputs. Seven Star LLC supplies the CA2KN40M7 in Oman and the GCC as an independent supplier based in Muscat.

The datasheet gives the device short name CA2K and the application as control circuit. The contact set is four normally open contacts, the coil is 220-230 V AC 50/60 Hz, and the utilisation categories are AC-15 and DC-13, the standard categories for control-circuit loads such as contactor coils and signal lamps.

Technical specifications of the CA2KN40M7

Contact set and operation of the CA2KN40M7

Because all four contacts make on energising, the relay is easy to document and to test: coil on means four closed paths, coil off means none. The relay can multiply a PLC output, separate circuits of different voltage that must not share a contact, or provide permissives to several machines from one signal.

Operating times in the datasheet: 10 to 20 ms coil de-energisation and NO opening; 10 to 20 ms coil energisation and NO closing. Non-overlap distance between NO and NC contacts: 0.5 mm. Mechanical durability: 10 Mcycles. Maximum operating rate: 10000 cyc/h.

Coil supply, contact ratings and low-level switching of the CA2KN40M7

The 220 to 230 V AC coil covers the lower end of the mains range and suits panels where the control supply is a single phase of a 220 V network or a 230 V supply with a negative tolerance. It is usually chosen for panels in which push-buttons and lamps are already wired at mains level.

The datasheet lists the coil voltage as 220 to 230 V AC 50/60 Hz. Operating limits: Drop-out: 0.2 to 0.75 Uc (at <50 °C); Operational: 0.8 to 1.15 Uc (at <50 °C). Inrush consumption: 30 VA (at 20 °C). Hold-in consumption: 4.5 VA (at 20 °C). Heat dissipation of the CA2KN40M7: 1.3 W. Immunity to micro-breaks: 2 ms.

The unit is also a typical replacement for aging 220 V relay banks in older switchrooms, where the printed coil voltage on the old relay decides the choice.

Conventional free-air thermal current: 10 A (at 50 °C). Rated making capacity: 110 A conforming to IEC 60947. Associated short-circuit protection: 10 A gG conforming to IEC 60947; 10 A gG conforming to VDE 0660. Minimum switching voltage: 17 V. Minimum switching current: 5 mA. Insulation resistance: > 10 MOhm. Rated operational voltage: <= 690 V <= 400 Hz.

The minimum switching figures matter when the relay is used to feed a PLC input or an electronic circuit at 24 V: contacts that normally carry amps can lose reliability at very low voltage and current, so the datasheet minimum should be respected or a different contact technology considered.

Family comparison for the CA2KN40M7

The CA2KN40B7 differs in coil 24 V AC 50/60 Hz against 220 to 230 V AC 50/60 Hz here. The CA2KN40P7 differs in coil 230 V AC 50/60 Hz against 220 to 230 V AC 50/60 Hz here.

The table lists the CA2K references of this group; contact set and coil are the only things that change, and the body, size and ratings are shared.

Selection checklist for the CA2KN40M7

Selection tip for the CA2KN40M7: the M7 version with four NO contacts serves 220 to 230 V panels. When it replaces a relay in a bank, check the old relay for an auxiliary block or an interface module fitted on top, and confirm that the arrangement still matches. Because all four contacts are normally open, the relay is also used as a pure repeater for a PLC output that must reach four separate circuits at different potentials, with the coil as the only common point.

• Confirm that no NC contact is needed; a 4 NO relay has none.
• Check that the four circuits can safely share one coil command.
• Coil voltage: 220-230 V AC 50/60 Hz; operating limits 0.8 to 1.15 times the rated voltage.
• Mounting: rail or plate, body 45 mm wide x 58 mm high x 57 mm deep.
• Short-circuit protection: use the associated 10 A gG fuse noted in the datasheet.

Mounting, wiring and environment for the CA2KN40M7

The relay mounts on a rail or on a plate, measures 45 mm wide x 58 mm high x 57 mm deep and weighs 0.18 kg. Terminals are screw clamps; the datasheet gives 1.3 N.m – on screw clamp terminals – with screwdriver flat Ø 6 mm, and accepted conductors from 0.34 to 4 mm squared depending on type and number. Fit a marker beside each screw group so that the NO and NC terminals are not confused during later maintenance.

The environment is stated as -25 to 50 °C in operation and -50 to 80 °C in storage, an altitude of 2000 m without derating, protection IP2X and a flame retardance of V1 to UL 94. The mechanical robustness data in the datasheet give vibration and shock withstand figures for both the open and closed state, which is useful for relays on moving or shaking machines.

Where the CA2KN40M7 is used in Oman and the GCC

With four normally open contacts and a 220 to 230 V coil, this relay repeats a single mains-level command to four circuits, for example the start permissive to several drives or the ‘plant on’ signal to separate pumps and fans.

The datasheet gives 10 million mechanical cycles and a maximum rate of 10,000 cycles per hour, so a four-contact relay can serve frequent switching duty without wearing out the mechanism, though contact life under load should be assessed separately.

Information to send with an RFQ for the CA2KN40M7

• Full reference (CA2KN40M7) 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
• Contact set needed: number of NO and NC contacts

Documents and quotation

A datasheet for the CA2KN40M7 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.