ZHUCO SZW26-25/7206.6 Eight-position six-section forward/reverse high/low speed milling machine changeover switch

SZW26-25/7206.6 Rotary Changeover Switch (Milling Machine Specific)
1. Product Overview
This product is a multi-functional rotary changeover switch with eight positions and six sections (layers), specifically designed to control the forward/reverse rotation, high/low speed, and stop functions of three-phase asynchronous motors in complex operating conditions. Its multiple contact sets work together to achieve complex motor winding switching, making it a key component in traditional machine tool electrical control systems.
2. Installation Characteristics
Panel mounting method is used, providing a stable structure. Specific mounting hole positions and panel opening dimensions should be based on the product drawings.
3. Electrical Parameters
Rated Voltage: AC 440V (50/60Hz); DC 240V
Rated Current: 25A
Contact Structure: Six independent contact layers, each containing a pair of contacts (normally open/normally closed configuration depends on the specific position logic). By rotating the handle to different positions, the contacts in each layer are driven to operate synchronously according to the preset logic (corresponding to the specific wiring diagram of model 7206.6), achieving switching of the motor windings from "forward high speed," "forward low speed," "stop," "reverse low speed," to "reverse high speed" states.
4. Structure and Materials
Contacts: Silver alloy material, capable of withstanding the surge current that may occur during motor starting and reversing, with good conductivity and arc resistance.
Conductors: Thickened copper parts, meeting the 25A rated current and frequent switching current carrying requirements.
Insulation and Mechanism: Made of flame-retardant and high-temperature resistant engineering plastic. The internal mechanism is a cam-slider operation mechanism, with clear positions and reliable operation, enabling synchronous and accurate switching of multiple signals.
Panel Marking: Standard marking is for milling machine functions (forward/reverse, high/low speed), customizable as needed.
5. Operating Environment Conditions
Ambient Temperature: -25°C to +40°C (average temperature within 24 hours ≤ +35°C)
Altitude: ≤ 2000 meters
Relative Humidity: ≤ 50% at +40°C; up to 90% at +20°C. Protection against possible condensation is required. 6. Mechanical and Electrical Life
Mechanical life: ≥ 100,000 cycles
Electrical life: ≥ 30,000 cycles (under rated load)
Operating frequency: Recommended ≤ 120 cycles/hour
7. Typical Application Scenarios
This switch is designed for motor control circuits requiring multi-speed and reversible operation, and is a reliable choice for direct manual control in both traditional and modernized equipment.
Core application: Used as the main control switch for machine tools such as universal milling machines, radial drilling machines, and boring machines, directly controlling the forward rotation, reverse rotation, high speed, low speed, and stop of the spindle motor.
Other equipment: Used in control cabinets of equipment requiring similar complex switching functions, such as mixers, lifting platforms, and large fans, to achieve manual selection of operating modes.
System integration: Can be used as a backup manual operation unit for PLC control systems, or as a core control switch in equipment with low levels of automation.