Phoenix Contact CBMC E4 24DC/1-10A NO Circuit Breaker

CBMC E4 24DC/1-10A NO: four-channel electronic circuit breaker for 24 V DC loads

The Phoenix Contact %s (order no. 2906032) is a multi-channel electronic circuit breaker that guards four separate 24 V DC load branches from a single DIN-rail module. Each channel is set to its own nominal current between 1 A and 10 A in 1 A steps, and the settings can be locked electronically so that nobody changes a protection value by accident after commissioning. The name decodes as follows: CBMC is the product family, E4 means electronic tripping with four channels, 24DC is the rated voltage, 1-10A is the adjustable current window, and NO describes the N/O remote-indication contact. The module is 36 mm wide, so four protected outputs take roughly the room of a single narrow terminal block.

Seven Star LLC supplies this device in Oman and the GCC as an independent supplier in Muscat, typically for control-panel builders and maintenance teams who want selective protection behind a 24 V DC power supply instead of a row of fuses or single-channel breakers.

Technical specifications of the CBMC E4 24DC/1-10A NO

How the CBMC E4 24DC/1-10A NO protects each output channel

Each of the four channels continuously measures its load current. When the current stays between 1.2 and 2.0 times the set nominal value, the channel switches off after about one second; a hard short circuit above twice the nominal current is cleared in 10 ms or less. After a trip the channel waits 5 seconds before it can be switched on again, and the front LED shows whether it is running normally (green), loaded above 80 % (yellow), or switched off because of overload, short circuit or a supply voltage outside the window (red). Because the module also switches off all outputs when the supply drops below about 17.8 V DC or rises above 30.5 V DC, connected electronics are never left running on a bad supply.

The integrated fail-safe element is rated 15 A DC per output channel and acts as the last line of defence. Phoenix Contact notes that repeated hard short circuits can reduce the melting integral of that backup fuse, so a channel that trips repeatedly should be investigated rather than simply reset.

Where the CBMC E4 24DC/1-10A NO fits in a 24 V DC system

This module is placed directly behind a 24 V DC power supply, for example a QUINT4, QUINT or TRIO unit, and splits the supply into protected branches for PLC racks, I/O blocks, sensors, valves and small drives. The input stage accepts up to 40 A in total, so one breaker can follow a 40 A supply, and further modules can be chained by bridging IN+. Related members of the same family are the CBMC E4 24DC/1-4A NO (2906031) for lower-current branches and the CBMC E4 24DC/1-10A IOL (2910411) with an IO-Link interface for remote parameter and status access.

Note that the module needs the negative pole on terminal IN- to power its internal electronics; return currents from loads must not be routed back to the supply through IN-.

Selection and ordering checklist

• Confirm every load branch needs 10 A or less; higher currents need a different protection device.
• Check that the supply stays inside 18 to 30 V DC, including ripple and any battery or UPS operation.
• Add up the branch settings and confirm the total stays within the 40 A input limit and the derating curve at your panel temperature.
• Check the capacitive load per channel (up to 45000 μF) for loads with large input capacitors.
• Decide whether a single N/O collective signal is enough, or whether IO-Link status (sibling 2910411) is required.
• Confirm the panel temperature: 40 A is available up to 35 °C, 24 A at 60 °C.

Installation, commissioning and maintenance

Snap the module onto a 35 mm DIN rail, wire the supply into the push-in IN+ and IN- terminals, and connect each load to its own OUT terminal. Use ferrules or solid conductors within the cross-sections in the table; the 10 mm stripping length applies to the main input terminals as listed by the manufacturer. Set each channel current using the front programming procedure (the yellow LED flashes in programming mode), then lock the values electronically. During commissioning, switch the channels on one at a time and compare the LED states with the expected load; a yellow LED means the channel is already loaded above 80 % of its setpoint and the nominal current should be reviewed.

For maintenance, record the set currents in the panel documentation, check that the remote contact reaches the PLC input, and keep one module as a spare if the branch protects critical control equipment. Mean time between failures is quoted at 8,403,361 h at 25 °C with 21 % load, but a real spare policy should depend on how long your site can run without the protected branch.

Typical applications in Oman and the GCC

In Oman and the GCC this breaker is a practical choice for compressor and pump control panels, switchgear auxiliary supplies, desalination plant instrumentation cabinets and power-generation control rooms, where a single shorted 24 V DC sensor should not take down a whole PLC panel. The 60 °C upper limit and the ISA G3 corrosive-gas listing shown on the datasheet suit enclosed panels in hot, dusty or coastal humid conditions, though enclosure ventilation and derating still need to be planned. Remote units on pipelines and wellheads benefit from the electronic locking of set currents.

Comparison with sibling devices

Information to send with an RFQ

• Full part number CBMC E4 24DC/1-10A NO and quantity.
• Supply voltage and power supply model feeding the breaker.
• Number of load branches and expected current per branch.
• Maximum panel temperature and whether UL or marine listings are needed.
• Whether a collective alarm contact or IO-Link is required.
• Delivery location in Oman or the GCC and target date.

Documents and quotation

Send us the part number CBMC E4 24DC/1-10A NO and the quantity you need, and we will confirm which official documents are available for this device. Seven Star LLC is an independent supplier in Muscat and quotes for projects across Oman and the GCC; we do not act on behalf of the manufacturer.

Please also tell us the delivery location and required timeline so that availability can be checked before you commit to a project schedule.