The 422029-2A is an AC tachometer generator produced by Reliance Electric. It is a precision electromechanical component that converts motor rotational speed into proportional AC voltage signals for speed feedback. This product is widely matched with legacy Reliance AC and DC drive systems. It has been discontinued officially, and only surplus, refurbished or used units are available for maintenance and replacement of old industrial equipment.

422029 is the base part number for Reliance AC tachometer generator series, specially designed for speed detection and feedback of industrial motors and drives. 2A stands for hardware revision and performance version, which defines standard electrical parameters and mechanical structure for medium and high speed motor monitoring.

This is a brushless permanent magnet AC tachometer generator with sturdy cast aluminum housing. The rated output voltage is 45V AC plus or minus 5 percent at 1000 RPM. It maintains linearity within plus or minus 0.5 percent throughout the working speed range from 60 RPM to 6000 RPM. It adopts 2-pole rotor structure with frequency response up to 200Hz and insulation class B. The operating temperature ranges from -20 degrees Celsius to 60 degrees Celsius, and the maximum allowable mechanical speed is 7200 RPM. The unit has a solid shaft with 19mm diameter for shaft coupling. The overall weight is about 3.2 kilograms.

It is equipped with a two-wire AC signal output interface with no polarity requirement. The output wires connect to the speed feedback terminals of the drive system. It is fixed by flange mounting and directly coupled to the motor shaft. It only transmits analog AC speed signals through hard wiring and has no digital communication function.

It captures the real-time rotational speed of the motor and converts mechanical rotation into stable AC voltage signals. It provides accurate speed feedback for drive control loops to realize closed-loop speed regulation. It features good linear performance and anti-vibration capability to ensure reliable signal output under harsh industrial working conditions. It serves as a key speed detection part to keep legacy drive systems operating normally.

It is mainly used as a speed feedback unit for various Reliance legacy AC and DC drives. It is applied to motor speed monitoring and control in manufacturing workshops, paper mills, textile factories and metal processing industries. It is a common replacement part for the maintenance and repair of old industrial motor control systems.

Install the tachometer generator on the motor end and align the shaft accurately during coupling to avoid extra mechanical stress. Fasten all mounting bolts firmly and check the connection of signal wires before operation. Conduct regular quarterly inspections to check shaft running status, tightness of mounting parts and integrity of output cables. Keep the housing clean and prevent dust and oil contamination. Disconnect related circuit power before disassembly and maintenance to ensure operational safety.