Uses high-current SCRs (often S8020L) and Diodes (D8020L) to rectify AC to DC and control the speed. Control Logic:
The is a high-performance DC motor speed controller commonly used in mini lathes like the CJ0618. It operates on 230VAC and provides a variable 0-180VDC output at up to 12ADC. Core Specifications Input Voltage: 230VAC, 50/60Hz. Output Voltage: 0-180VDC. Rated Current: 12ADC.
The logic circuit blinks an internal LED inside the optocoupler.
If you can provide the printed on your board (e.g., PGFUN, generic) or tell me the exact component that failed , I can help you find a more accurate diagram or suggest a replacement part. g., "What is the value of R15?") Upgrade the current capacity What is the symptom you are seeing? jymc220bi schematic full
The control panel features multiple trimmer potentiometers (often labelled on the physical board as P1, P2, P3, MIN, MAX, ACCEL, and DECEL):
The is a common DC brush motor speed controller used primarily in mini lathes like the CJ0618. While a single official "full" internal schematic is rarely published by the manufacturer, it is functionally equivalent to the KBIC-120 or SCR340 series controllers. Core Specifications Input Voltage: 230 VAC (50/60 Hz). Output Voltage: 0–180 VDC. Rated Current: 12 ADC (Armature DC).
If you are currently diagnosing a broken control board, let me know your lathe is showing (e.g., completely dead, blowing fuses, or running at full speed) or which components look physically damaged , and I can guide you through the exact multimeter tests to isolate the problem. Share public link Uses high-current SCRs (often S8020L) and Diodes (D8020L)
Before mapping the schematic architecture, verify your hardware footprint against the standard industrial configurations:
Usually employs Silicon Controlled Rectifiers (SCRs) or power transistors mounted to a large aluminum heat sink to pulse-width modulate the power pushed to the motor's armature.
: Delivers 0–180V DC variable power to the brush motor. If your lathe spins backward relative to your control switch position, swap these two lines. Core Specifications Input Voltage: 230VAC, 50/60Hz
Adjusts the starting voltage when the main potentiometer is turned to zero.
The main power grid line feeds directly into the primary filtering block to scrub high-frequency noise and protect internal logic components.
1PC DC speed control board JYMC-220B-II 12A 115V lathe control board Go to product viewer dialog for this item. Input Voltage 230VAC ±10% (50/60 Hz) Input Voltage 115VAC ±10% (50/60 Hz) Output Voltage 0–180 VDC Output Voltage 0–110 VDC / 0–180 VDC Rated Current 12A DC Continuous Rated Current 12A DC Continuous Drive Technology SCR Thyrister Phase Control Drive Technology SCR Thyrister Phase Control Compatible Motors 450W – 1100W Brushed DC Compatible Motors 450W – 1100W Brushed DC The Full Architectural Schematic Breakdown
The switching device is likely shorted internally, feeding full voltage to the motor.
Often, repairing the board without a full schematic is possible by tracing the PCB and testing components like the MOSFET and bridge rectifier.