Shunt trip
Shunt release coils: accessories for remote tripping and undervoltage control in modular boards.
- Function: remote trip or undervoltage release according to the device installed.
- Voltage: 230V AC supply for integration in modular panels.
- Format: compact DIN-rail accessory with one-module design.
- Use: control, safety and automation of protection devices.
MCB releases: S24BE shunt trip and S24BM undervoltage release
Solera S24BE and S24BM are accessories that act on the opening mechanism of a compatible MCB. They add a control function or voltage-drop tripping function to the assembly. They are not replacement contactor coils or standalone switching devices. Start selection with the required function: S24BE receives an electrical trip command; S24BM is designed to trip when its supply voltage drops.
Differences between S24BE and S24BM
| Reference | Function | Supply | Format | Declared compatibility |
|---|---|---|---|---|
| S24BE | Shunt trip: remote opening by electrical command | 230 V AC, 50/60 Hz | 1 module of 18 mm | S24M.. |
| S24BM | Undervoltage: tripping on a supply voltage drop | 230 V AC, 50/60 Hz | 1 module of 18 mm | S24M.. |
Applications and selection criteria
Consider S24BE where a panel needs an external command to open the MCB. Consider S24BM where the required function is tripping when the supply monitored by the release decreases. These operating principles differ: interruption of the control supply must not be interpreted as a shunt-trip command. Both data sheets identify industrial environments as a typical application.
Check the exact MCB reference, mechanical coupling and assembly wiring diagram. The data sheets state an engageable connection and compatibility with S24M..; this does not establish compatibility with every MCB, residual current device, RCBO or another brand’s device. A 35 mm DIN rail format and one-module width describe mounting dimensions, not universal mechanical compatibility.
Check that the control circuit supplies 230 V AC at 50/60 Hz and that its output suits the coil consumption and duty. Do not infer operation at 24 V or on DC. For undervoltage operation, verify the assembly’s operating thresholds and tripping and resetting conditions rather than adopting values from other accessories. Both data sheets specify an ambient operating temperature of −5 to +40 °C.
Frequently asked questions
Can S24BE or S24BM be fitted to any modular MCB?
That compatibility is not declared. Both data sheets identify S24M.. as the compatible family. Before fitting an accessory, check the specific reference, coupling and instructions for both the MCB and the release. A shared brand or modular width is insufficient.
Does S24BM automatically close the MCB when voltage returns?
The data sheet declares undervoltage tripping, not automatic reclosing. Restoration of the supply must not be confused with a closing command. Check the assembly’s resetting conditions before defining the operating sequence.
Do these releases replace overload or short-circuit protection?
No. The MCB protects the circuit; the release adds a way of actuating its opening mechanism. The release must not be treated as an overvoltage limiter either. Protection and breaking capacity must be selected for the relevant assembly and installation.