4p Red devil Fan Simulator for Antminer Innosilicon Goldshell iPollo Miner

4-Pin Fan Speed Simulator – Universal Plug-and-Play for Antminer, Innosilicon, Goldshell & iPollo

This 4-pin fan speed simulator (also known as the Red Devil) generates a tachometer signal equivalent to 6,600–7,300 RPM using an NE555 timer circuit, allowing the miner control board to detect a running fan even when the original fans have been removed. It uses a standard 4-pin B3 interface and is compatible with Antminer, Innosilicon, Goldshell and iPollo miners — any unit that expects a 4-pin fan tachometer feedback signal. Simply plug the simulator into the fan header and the miner will boot and operate without triggering fan-speed alarms or protective shutdowns.

Why Use a Fan Simulator

Miners that have been converted to water cooling, oil immersion, or external ventilation no longer need their original fans, but the firmware still monitors fan speed on every header and will shut down the machine if no tachometer signal is detected. A fan simulator solves this by feeding the control board a steady square-wave signal within the expected RPM range. This is essential for immersion-cooled setups where fans would be destroyed by the cooling fluid, and for custom air-cooled enclosures where larger, quieter external fans replace the stock high-RPM units but connect through a different interface.

Installation

Power off the miner and disconnect the original fan cable from the 4-pin header on the control board. Plug the simulator directly into the same header — the B3 connector is keyed so it can only be inserted in the correct orientation. Power on the miner and check the dashboard or firmware log to confirm the simulated fan speed reads between 6,600 and 7,300 RPM. If the miner has multiple fan headers, install one simulator per header that no longer has a physical fan connected. The NE555-based circuit draws negligible current and generates no heat, so no additional cooling or mounting hardware is required.

This simulator is a universal replacement for any 4-pin tachometer-monitored fan header. For miners using 6-pin fan connectors (common on newer Whatsminer models), check our range of 6-pin simulators instead.

4-Pin Fan Simulator Specifications

Related Fan Speed Simulators

• Antminer L9 Fan Speed Simulator
• IceRiver AL3 KS5M Fan Speed Simulator
• IceRiver Fan Simulator – RX0 KS1 KS2 KS3 Series
• DragonBall A11 KS6Pro Dual Fan Simulator – Hydro Cooling

Converting miners to immersion or water cooling? Contact us at contact@lys-sz.com — we carry fan simulators for every major miner brand and connector type.

Worldwide shipping from our Shenzhen warehouse.