B4.85 - Square D Thermal Unit

B4.85 - Square D Thermal Unit

Looking for dependable motor overload protection? The Schneider Electric B4.85 Thermal Unit delivers responsive thermal overload safeguarding (Class 20) for NEMA Type S motor starters. Engineered with a melting-alloy mechanism, this unit trips precisely during overload events—keeping your motors safe and production flowing smoothly.

Key Features & Benefits

• High-Sensitivity Tripping: Utilizes a precision melting alloy to accurately sense overloads, reducing false trips and protecting motor health.
• Consistent Performance: Designed for reliable, repeatable operation under real-world industrial conditions.
• Easy Plug-and-Play: Streamlined mounting compatibility with standard NEMA Type S motor starters speeds up replacement and maintenance.
• Industrial Durability: Built with quality materials to resist wear in harsh environments like manufacturing plants and process facilities.

Technical Specifications

• Overload Type: Melting alloy
• Class: 20 (fast thermal response)
• Current Range (Full Load Rating): 3.00–3.42 A
• Voltage Rating: 600 VAC
• Mounting: Plug-in for NEMA Type S starters
• Dimensions: 2.4 in × 1.1 in × 0.8 in
• Weight: 0.64 oz (18.14 g)

Material Compliance & Certifications

• Certifications: CE‑certified for global safety and performance standards
• Environmental Compliance: PVC‑free components for reduced environmental impact
• California Proposition 65: Contains lead/lead compounds; standard warning applies

Where It Works Best

Ideal for:

• Heavy-duty manufacturing environments
• Processing plants with frequent load cycling
• Commercial HVAC and pumping systems
• Routine maintenance and equipment upgrades on NEMA Type S starters.