Lovato SM1R2500 Rotary Motor Protection Breaker 20-25 A

Lovato SM1R2500 rotary motor protection breaker, 20 to 25 A

The Lovato SM1R2500 is the rotary-handle version of a 20 to 25 A motor protection circuit breaker. It protects three-phase motors up to about 11 kW at 400 V against overload, short circuit and phase loss and provides a rotary isolating handle. Seven Star LLC supplies the SM1R2500 in Oman and the GCC as an independent supplier in Muscat.

In the code SM1R indicates the rotary family and 2500 means 25 A rated current. It is the top-of-range companion to the SM1R2300, and the next step above it is the SM1R3200 for 24 to 32 A. Compared with the SM1P2500, the electrical band is the same, but the breaking figures in the catalogue are higher at 400 V, which can decide the choice in a tight panel.

SM1R2500 technical specifications

SM1R2500 breaking capacity compared with the SM1P2500

At 400 V the SM1R2500 lists Icu of 50 kA and Ics of 25 kA, which is notably higher than the 15 kA and 5 kA of the SM1P2500 at the same voltage and current band. At 690 V the Icu is 4 kA. For a panel with a fault level between 15 and 50 kA at 400 V, this makes the rotary breaker a way to avoid adding a fuse upstream.

The Ics figure matters for continuity of service: at 25 kA the breaker is expected to remain usable after a fault of that size, which the lower Ics of other versions cannot promise.

How the SM1R2500 operates

Turning the handle to on closes the contacts; a bimetal element follows the motor current and trips on overload by the class 10A curve, while a magnetic element trips at 13 times the rated current. A phase-loss mechanism shortens the thermal trip when a phase fails. The handle shows a distinct tripped position, so operators see the difference between a manual off and a protective trip.

Using the SM1R2500 in a starter

Combine it with a BF2510A230 contactor for a 25 A AC-3 duty, or with a BF1810A230 for a motor at the lower part of the band. The breaker handles isolation and protection and the contactor takes the daily switching, so the 100,000-cycle electrical life of the breaker is not used up by routine starts.

SM1R2500 selection checklist

• Motor current between 20 and 25 A
• Fault level against 50 kA Icu and 25 kA Ics at 400 V
• Voltage: only 4 kA Icu at 690 V
• Rotary handle needed
• 200 A class J fuse for UL motor-disconnect documentation
• Panel ventilation for up to 2.83 W per pole
• Conductor size and terminal capacity

Installing and maintaining the SM1R2500

Mount on 35 mm rail or screws, and strip 12 mm of conductor. Tighten to 2.5 to 3 Nm with a PH2 screwdriver and size the cable for the full 25 A. Set the dial, trip-test the handle and record the setting.

Routine checks include thermal imaging of terminals during loaded operation, handle exercise and comparison of the measured current with the setting. If the breaker trips on a short circuit, inspect the motor insulation before resetting.

Typical SM1R2500 applications in Oman and the GCC

Typical loads are air compressors, cooling fans, medium pumps and workshop machinery in industrial areas such as Sohar, Rusayl and Duqm. The rotary handle gives a visible on, off and tripped indication, which helps where permit-to-work rules call for a clear isolation point at the starter panel.

SM1R2500 neighbouring parts

For panels with a mix of breakers, using the same band in both front styles keeps spare-part stocking simple. A maintenance store can hold the SM1R2500 together with the SM1R2300 and SM1R3200 and cover the whole 17 to 32 A window with three devices. Remember that every motor needs its own dial setting, so the stock part is only the starting point and the final setting must always come from the nameplate.

Information to send with an RFQ for the SM1R2500

• Part number SM1R2500 and quantity
• Motor nameplate
• Fault level at the board
• UL or IEC documentation requirement
• Ambient temperature
• Delivery address

Site conditions in Oman for the SM1R2500

Low-voltage switching and protection devices in Oman often sit in motor control centres and outdoor panels where internal temperatures are high for much of the year. When you select the SM1R2500, check its rated values at your real ambient temperature, as stated in the manufacturer documentation, and confirm the coordination with upstream protection and with the motor or load it serves. Short-circuit levels differ from site to site, so verify the breaking capacity required at the point of installation.

Standardising ratings and coil voltages across a project reduces the number of spare part numbers that need to be stocked. Keeping a small stock of the SM1R2500 and recording settings such as trip ranges or ramp times shortens repair work during a breakdown.

Documents and quotation

Send the part number SM1R2500 and we will confirm the documents available for it, such as the technical data sheet, wiring diagram and instruction sheet, together with availability and lead time.

Seven Star LLC is an independent supplier in Muscat and is not an official channel of the manufacturer. Share the quantity, delivery location and project reference with the request and we will answer with a formal quotation.