1、This regulated power supply is a simple, accurate DC power source with full indicated power. 2、It provides power source for factory maintenance, calibration positions, and can be integrated into test&equipment cabinet. 3、It powers the DIY circuit in our work table at home and is also a necessary tool for educational institute particularly for those involve electronics and telecommunications majorities. 4、High as 80% power efficiency 5、A secondary voltage stabilization circuit through MOS ensuring a superb voltage output Features: Our power supply allows you to have a stable and accurate output as your device or load exactly needed. This regulated power supply is a simple, accurate DC power source with full indicated power. It provides power source for factory maintenance, calibration positions, and can be integrated into test&equipment cabinet. It powers the DIY circuit in our work table at home and is also a necessary tool for educational institute particularly for those involve electronics and telecommunications majorities. High as 80% power efficiency Small size as 3 U high appropriately fit for work station or test equipment cabinet. Specification: Model: STP3005DH Voltage: 110V Output voltage: 0-30v Output current: 0-5A Digital: 4 digital led Working temperature: 0 ~ 40℃ Relative humidity: 80% Fuse:  F5AL, 250VAC Regulation rate:  0.03% + 1mV Load regulation rate:  0.33% Ripple and noise: 3mVrms (5Hz ~ 1MHz); <10Vppm CURRENT REGULATION Regulation rate:  0.1% + 1mA load regulation rate: 0.2% +5mA Ripple and noise: 3mArms Restore: 300ps (with toad of 50% regulation rate, 0.5A) Leak current:  1mA (with input 1500VAC/ls to ground) Insulate resistance: 5MQ (with input 500VDC/5s to ground) Temperature:  -10 ~ 70°C Relative humidity: 70% Size:13*21.5*8.5cm/5.1*8.5*3.3in Weight: Approx.1591g/56.1oz Operation Instruction: (3) Use a wire with one end in Ground Port and another end to earth. (5) Turn off the power by pressing the "Power Switch", short out "positive connector"and "Negative Connector" with a wire (6) Press " Power Switch'' to turn on the device. Coarsely or fine tune the current knob to get a wanted current. And then remove the wire. (7) Connect a load positive to positive port (green), negative to negative port(black) Package list: 1 * Regulated DC Power Supply 1 * Power cable 2 * crocodile clip 1 * instruction Note: 1.The device is intended for indoor use only 4.Do not open repair the device or it will void the warranty. 5.Do not use the device in a damp environment. 6.Keep the device away from heat or water, magnetic field. 7.Keep the device and all loose parts (if any) away from children, pets and unauthorized persons. 8.Don't sharply bend, cut, extend knot, step on or pull the cord but on the 9.When the device is damaged in any way, stop using it immediately. 10.If the device is not in service for long, unplug the power. 11.Use the spare parts with same specification as original one.