I am having issues with the laser being at full power all the time. (PWM has 5 volts won't do variable voltage) I have used the suggested 3 wire instructions. I also tried the spindle 0 to 10v and it reacts the same way. This should be able to adjust power for different power output for engraving and cutting. Any firmware settings I need to check? Am I missing something? NEJE 450nm 20W Laser Module Wavelength 450nm Radiator Size 30*80mm Material Copper + Aluminum Weight 202g Drive Position Built-in Is the Power Adjustable PWM can be adjusted Drive Protection Surge Protection, Overvoltage Protection Input Power approx. 12V2A, about20W (without fan power) Output Optical Power 5.5W Line Length 300mm Control Line Installation Method Pluggable Fan Size 30*10mm Fan Speed 15000 rpm Controllable Temperature Less than 60 degrees Celsius PWM 20KHz / 3.3V Temperature Sensor Yes Focus Range 40mm-60mm ( 50mm is best) Focus Diameter 0.05mm Best Focal Length 10mm from the light exit Interface Specification 4pin PH2.0 (red: 12V, black: GND, yellow: PWM, green: temperature signal) Main Applications Paper cutting, Wood cutting(<5mm), Depth Engraving, g-code drawing... Note 1. It is heavier, not suitable for engraving, only suitable for cutting. 2. Please apply this module under the premise of safety protection! 3. Recommended application machine: NEJE Master. 4. NEJE Master comes standard with 12V2A charger. If you want to upgrade your old machine, you need to prepare another 12V3A power supply.