The MSD 75643-HC high-current four-channel solid-state relay (black version) delivers 35A continuous current per channel, totaling 140A. It supports PWM control of electronic fans and water pumps and features built-in protection and LED diagnostics.

Specification

• Original Part Number (MPN): 75643-HC
• Type: High-current solid-state relay module (no mechanical contacts)
• Number of channels: 4 independent channels
• Continuous current per channel: 35 A
• Total output: 140 A
• Short-term overload: 40 A for 35 seconds; 50 A for 12 seconds; 60 A for 8 seconds.
• Power supply voltage: 7 – 20 V
• PWM control: Supported, duty cycle 50-90% (can operate continuously for 30 minutes); short-term usability 30-90%.
• Triggering method: Single-wire trigger per channel, can be connected to 12V or ground.
• Trigger wire diameter: 18 – 22 AWG
• Recommended mains power cable gauge: 2 AWG for 140 A, 4 AWG for 80 A, 6 AWG for 60 A, and 8 AWG for 35 A.
• Protection functions: Automatic over-temperature, short-circuit, and overload protection; after overheating trips, the circuit locks and must be reset to recover.
• Status indication: Independent LED for each channel
• Installation: Includes mounting hardware; the mounting feet can rotate 90° to accommodate different installation positions.
• Casing color: Black
• The box contains: 1 solid-state relay module, 1 mounting kit, and 5 packs of Loctite 242 screw fixing adhesive.