Danfoss 117U3188 SC18MLX Motor Protector

The Danfoss 117U3188 is a heavy-duty internal motor protector designed specifically for the SC18MLX compressor series. Engineered for high back pressure (HBP) applications, this thermal protection switch serves as a critical safeguard against winding overheating and overcurrent conditions. In the field, field technicians rely on this hermetic compressor part to prevent permanent stator damage during stalled rotor conditions or extreme voltage fluctuations. The 117U3188 utilizes precise bi-metal disc technology to interrupt the circuit when internal temperatures exceed safe operating limits, ensuring the Danfoss compressor remains within its design parameters. Integration is straightforward within the electrical housing, maintaining a secure connection to the compressor terminal pin. Selecting the correct refrigeration motor protector is essential for maintaining system pressure and avoiding premature HVAC compressor failure. This genuine replacement electrical component ensures the SC18MLX maintains steady performance in commercial refrigeration systems where consistent cooling cycles are mandatory.

• Specifically calibrated for the Danfoss SC18MLX electrical profile to prevent nuisance tripping.
• High-speed reaction to overcurrent protection needs during high ambient temperature operation.
• Robust construction resists mechanical vibration found in HBP refrigeration units.
• Maintains compressor lifecycle by preventing insulation breakdown due to excessive heat.
• Direct OEM fitment ensures seamless installation on existing terminal configurations.

How do I verify if the 117U3188 is tripped?
Use a multimeter to check for continuity across the terminals. An open circuit during a cooling demand usually indicates the protector has tripped due to thermal overload or high amperage draw.

Is this protector compatible with compressors other than the SC18MLX?
While this component shares similarities with other Danfoss protectors, it is specifically tuned for the electrical load and temperature threshold of the SC18MLX. Using it on different models may result in inadequate protection or frequent short-cycling.

Does a tripped motor protector indicate a bad compressor?
Not necessarily. It often indicates an external issue such as a failed start capacitor, dirty condenser coils, or a voltage drop. The protector is doing its job by sacrificial interruption before the windings burn out.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.