Eaton ZB12-12 Thermal Overload Relay, 9-12 A, 3-Pole, Class 10A, 1NO+1NC, Direct Mount 278441

Protect motors from overheating and phase failure with the Eaton ZB12-12 thermal overload relay. It monitors current in three phases and trips when an overload condition persists, preventing damage to motors and equipment. With an adjustable current range of 9 to 12 A, it suits many small to medium three-phase motors. The relay offers both manual and automatic reset, selectable via a front dial, and provides one normally open and one normally closed auxiliary contact for control signaling. It mounts directly onto Eaton DILM7 to DILM15 contactors, forming a compact motor starter, or can be panel-mounted using an adapter (adapter not included).

Who is it for

This relay is intended for panel builders, maintenance technicians, and machine builders who need reliable motor protection in industrial control panels. It is suitable for applications such as pumps, fans, conveyors, and compressors where motors are started directly on line.

Main features

• Adjustable thermal overload trip setting from 9 A to 12 A
• Three-pole protection with phase loss sensitivity
• Class 10A tripping characteristic for normal motor starting
• 1 NO + 1 NC auxiliary contacts for status feedback
• Manual or automatic reset selectable
• Direct mounting on Eaton DILM7...DILM15 contactors
• Rated short-circuit withstand current 150 A
• Main circuit wire size 0.75 to 4 mm²

Specifications

• Product type: Thermal overload relay
• Current adjustment range: 9 - 12 A
• Rated operational current (Ie): 12 A
• Rated short-circuit withstand current (Icw): 150 A
• Wire cross-section (main circuit): 0.75 - 4 mm²
• Rated insulation voltage (Ui): 690 V
• Rated impulse withstand voltage (Uimp): 6 kV
• Number of poles: 3
• Trip class: Class 10A
• Auxiliary contacts: 1 NO + 1 NC
• Mounting: Direct on DILM7-DILM15 or standalone
• Ambient operating temperature: -25 to +55 °C
• Weight: 145 g

Tips

Set the current adjustment dial to the motor's full-load current as shown on its nameplate. For motors with long starting times, ensure the trip class matches the application. Use the test button to verify the relay trips correctly before commissioning.