1. Battery-powered generator with a rechargeable lithium battery. 2. When the battery voltage is low, the undervoltage indicator light will illuminate. Turn off the generator and recharge the battery promptly. 3. If the generator is not used for an extended period, recharge the battery at least every two months to prevent damage. Micro USB powered and charged. 1) Current Output: Turn the current output encoder to the right to increase output; turn it to the left to decrease output. You can change the cursor position with the encoder button to adjust output steps and decrements (0.01mA, 0.1mA, 1mA, 10mA). 2) Voltage Output: Turn the voltage output encoder to the right to increase output; turn it to the left to decrease output. You can change the cursor position with the encoder button to adjust output steps and decrements (0.01V, 0.1V, 1V, 10V). 3) 24V Voltage Output: 24V will be output directly upon power-on. 4) Output Adjustment: Press and hold the current output encoder button for over 2 seconds to enter the calibration interface. The current output calibration range is ±9.99%, and the voltage output calibration range is ±9.99%. Corresponding current and voltage values can be calibrated by rotating the respective encoders. Press the voltage encoder button to save settings; press the current encoder button to cancel settings. Note: Due to output chip limitations, the minimum output voltage and current cannot be 0! Specifications: Active Current Output: 0-22 mA (minimum output is approx. 0.06 mA), Load: 0-550 Ω Passive Current Output: 0-22 mA (minimum output is approx. 0.06 mA), External power supply up to 30V, Load: 0-550 Ω Voltage Output: 0 V-12 V (minimum output is approx. 0.05 V) 24V Voltage Output: Control Current: 35 mA (do not exceed 35 mA) Operating Environment: 0°C-50°C non-condensing Item Size: 90 * 70 * 28 mm / 3.54 * 2.76 * 1.10 inches Package Size: 150 * 100 * 80 mm / 5.91 * 3.94 * 3.15 inches Package Weight: 120 g / 4.23 ounces Package List: 1 * Signal Generator