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MITSUBISHI ELECTRIC
[MITSUBISHI ELECTRIC] — UN-FD, FD4 Fault Detection Units (Contact Weld Detection Relays)
Family ID: MEL-OPT-FD
Mitsubishi Electric UN-FD and UN-FD4 fault detection units detect main circuit contact welding of magnetic starters, cutting off power in combination with a circuit breaker or contactor to prevent load equipment runaway. UN-FD for 200V main circuits (output 1c fixed, resets when the main circuit opens); UN-FD4 for 400V main circuits (output 1a or 1b selectable, also detects non-operation faults, resets by switching off the control supply). Detection time 0.2 to 0.5s. CX types have CAN terminals. Not applicable to capacitor loads, star-delta starting, or inverter circuits. DC24V control supply versions available on request.
12 product codes available in this family
Product Codes & Specifications
| Product Code | Description | Brand | Spec | ||
|---|---|---|---|---|---|
| UN-FD AC100V | Fault detection unit UN-FD, 200V main circuit, AC100V | MITSUBISHI ELECTRIC | Main Circuit: 200V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1c (fixed) · Terminal: Screw | ||
| UN-FD AC200V | Fault detection unit UN-FD, 200V main circuit, AC200V | MITSUBISHI ELECTRIC | Main Circuit: 200V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1c (fixed) · Terminal: Screw | ||
| UN-FDCX AC100V | Fault detection unit UN-FDCX, 200V main circuit, AC100V | MITSUBISHI ELECTRIC | Main Circuit: 200V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1c (fixed) · Terminal: CAN (CX) | ||
| UN-FDCX AC200V | Fault detection unit UN-FDCX, 200V main circuit, AC200V | MITSUBISHI ELECTRIC | Main Circuit: 200V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1c (fixed) · Terminal: CAN (CX) | ||
| UN-FD4 AC100V 1A | Fault detection unit UN-FD4, 400V main circuit, AC100V, 1a | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1a · Terminal: Screw | ||
| UN-FD4 AC100V 1B | Fault detection unit UN-FD4, 400V main circuit, AC100V, 1b | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1b · Terminal: Screw | ||
| UN-FD4 AC200V 1A | Fault detection unit UN-FD4, 400V main circuit, AC200V, 1a | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1a · Terminal: Screw | ||
| UN-FD4 AC200V 1B | Fault detection unit UN-FD4, 400V main circuit, AC200V, 1b | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1b · Terminal: Screw | ||
| UN-FD4CX AC100V 1A | Fault detection unit UN-FD4CX, 400V main circuit, AC100V, 1a | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1a · Terminal: CAN (CX) | ||
| UN-FD4CX AC100V 1B | Fault detection unit UN-FD4CX, 400V main circuit, AC100V, 1b | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC100V (AC100-120V 50/60Hz) · Output Contact: 1b · Terminal: CAN (CX) | ||
| UN-FD4CX AC200V 1A | Fault detection unit UN-FD4CX, 400V main circuit, AC200V, 1a | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1a · Terminal: CAN (CX) | ||
| UN-FD4CX AC200V 1B | Fault detection unit UN-FD4CX, 400V main circuit, AC200V, 1b | MITSUBISHI ELECTRIC | Main Circuit: 400V class · Control Voltage: AC200V (AC200-240V 50/60Hz) · Output Contact: 1b · Terminal: CAN (CX) |
