Why Choose the ABB OTM1250E3CM230C 1250A Motorised Changeover Switch?
The ABB OTM1250E3CM230C is a heavy-duty 1250 A three-pole motorised changeover switch designed for reliable electrical power source transfer in industrial and commercial low-voltage distribution systems. Part of the ABB OTM motorised changeover switch range, it combines high-current switching capability with an integrated motor operator, enabling electrically controlled transfer between two alternative power supplies.
Featuring a 220–240 V AC motor operating supply, the OTM1250E3CM230C provides a practical solution for applications requiring remote or electrically initiated changeover operations. Its I–0–II switching arrangement allows selection between Source I, an isolated centre-off position and Source II. The open-transition mechanism disconnects one supply before connecting the other, helping prevent unintended parallel operation of independent electrical sources.
With a rated operational current of 1250 A for AC-21A and AC-22A applications at voltages up to 690 V AC, the OTM1250E3CM230C is suitable for substantial electrical distribution loads. Its integrated motor operator, manual operating handle and robust switch-disconnector construction make it suitable for generator changeover systems, industrial switchboards, commercial buildings and electrical installations requiring dependable power source management.
Key Advantages
- 1250 A rated operational current for high-capacity industrial and commercial power distribution.
- Three-pole configuration suitable for switching three-phase electrical supplies.
- Integrated motor operator enables electrically controlled and remote changeover operation.
- 220–240 V AC motor supply suitable for compatible industrial control systems.
- I–0–II switching positions provide selection between two supplies and a centre-off position.
- Open-transition operation disconnects one source before connecting the alternative source.
- 1250 A AC-21A and AC-22A ratings at 380–415 V, 500 V and 690 V AC.
- 50 kA short-time withstand current for 1 s supports appropriately coordinated electrical distribution installations.
- 1000 V rated insulation voltage for low-voltage switchgear applications.
- Supplied with a manual operating handle for local operation when required.
- Includes terminal fastening hardware and control circuit connectors.
- Compatible with suitable external automatic transfer controllers for ATS applications.
- Robust ABB OT-series construction designed for industrial switchboard integration.
Key Features
- ABB OTM motorised changeover switch series.
- OTM1250E3CM230C motor-operated changeover switch.
- 1250 A rated current.
- Three-pole (3P) switching arrangement.
- 220–240 V AC motor operating voltage.
- I–0–II operating positions.
- Open-transition, break-before-make switching principle.
- Integrated electrical motor drive.
- Manual operation using the supplied handle.
- Base-mounted construction for switchboard installation.
- 1000 V rated operational and insulation voltage.
- 12 kV rated impulse withstand voltage.
- 50 kA / 1 s short-time withstand current.
- 1250 A AC-23A operational rating at 380–415 V AC.
- 1000 A AC-33B operational rating at 415 V AC.
- Supplied with manual operating handle, terminal bolt kit and control circuit connectors.
- Suitable for integration with compatible power source monitoring and transfer control equipment.
Technical Specifications
- Manufacturer: ABB
- Series: OTM Motorised Changeover Switches
- Product family: OT Changeover Switches
- Model: OTM1250E3CM230C
- ABB order code: OTM1250E3CM230C
- ABB catalogue product ID: 1SCA112676R1001
- Product type: Motorised changeover switch
- Product group: OT Change over Switches
- Rated operational current: 1250 A
- Number of poles: 3
- Pole configuration: 3P
- Motor operating voltage: 220–240 V AC
- Nominal motor supply: 230 V AC
- Motor operator: Integrated
- Operating positions: I–0–II
- Changeover type: Open transition
- Operating method: Electrical motor operation with manual operating provision
- Rated operational voltage: Up to 1000 V AC
- Rated insulation voltage (Ui): 1000 V
- Rated impulse withstand voltage (Uimp): 12 kV
- Rated operational current AC-21A: 1250 A at 380–415 V, 500 V and 690 V AC
- Rated operational current AC-22A: 1250 A at 380–415 V, 500 V and 690 V AC
- Rated operational current AC-23A: 1250 A at 380–415 V, 500 V and 690 V AC
- Rated operational current AC-31B: 1250 A at 415 V AC
- Rated operational current AC-33B: 1000 A at 415 V AC
- Rated operational power at 400 V: 710 kW (AC-23A)
- Rated operational power at 500 V: 900 kW (AC-23A)
- Rated operational power at 690 V: 1200 kW (AC-23A)
- Rated short-time withstand current (Icw): 50 kA rms for 1 s
- Conventional free-air thermal current: 1250 A at 40 °C
- Power loss: 29 W per pole at rated operating conditions
- Mounting type: Base mounting
- Operating mechanism location: End of switch
- Product dimensions (W × H × D): 507 × 306 × 297 mm
- Net weight: Approximately 55 kg
- Supplied accessories: Manual operating handle, terminal bolt kit, control circuit connectors, handle storage clip and spare fuses
- Country of origin: Finland
- EAN / GTIN: 6417019453910
- Applicable product standard: IEC/EN 60947-3
Reliable Motorised Power Source Transfer for High-Current Installations
The ABB OTM1250E3CM230C provides an electrically operated solution for transferring electrical loads between two alternative supplies. In a typical mains-to-generator installation, Source I represents the normal electrical supply and Source II represents the standby generator. The integrated motor operator allows the changeover mechanism to be operated through a compatible control circuit rather than requiring every transfer to be performed manually.
Its I–0–II operating sequence provides a defined centre-off position between the two supply selections. The open-transition arrangement ensures that the first source is disconnected before the alternative source is connected, making the switch suitable for systems where independent electrical supplies must remain separated.
The 1250 A three-pole switching arrangement is intended for substantial three-phase electrical loads. ABB specifies operational current ratings according to IEC utilisation categories, including AC-21A, AC-22A, AC-23A, AC-31B and AC-33B. These classifications help engineers select the switch according to the characteristics of the connected load rather than relying solely on its nominal current rating.
The OTM1250E3CM230C incorporates an integrated 230 V AC motor operator, but it is not by itself a complete automatic transfer switch controller. Automatic mains failure detection, generator start commands, transfer timing and supply monitoring require a suitably designed external control system or compatible ABB automatic transfer control equipment.
For maintenance and commissioning, the supplied manual operating handle provides an alternative means of operating the switch in accordance with ABB's operating instructions. Its base-mounted design, supplied terminal fastening hardware and control connectors support integration into purpose-built low-voltage switchboards and electrical distribution assemblies.
Typical Applications
- Industrial mains-to-generator changeover installations.
- Motorised transfer between normal and standby electrical supplies.
- Commercial building electrical distribution systems.
- Industrial low-voltage switchboards and switchgear assemblies.
- Automatic transfer switch systems with suitable external controllers.
- Manufacturing plants and production facilities.
- Data centres and critical infrastructure power distribution.
- Hospital and healthcare facility standby power systems.
- Industrial pumping stations and water treatment facilities.
- Large commercial and institutional electrical installations.
- Utility and infrastructure power distribution systems.
- Remote-controlled power source selection applications.
- OEM electrical switchgear and industrial panel building.
