Key functions and benefits LCD display for clear numeric readout during tests. Four-wire socket (4-wire connection): provides one set for loop power and one set for loop testing to reduce lead error and improve measurement accuracy. Built-in Mini USB port and DC 5V input for convenient power or charging. Device includes an internal lithium battery for portable operation. ESR reference table included for quick comparison of capacitor ESR values. Zero (null) key to remove probe open-circuit offset when measuring capacitance and to remove probe short-circuit offset when measuring capacitance or ESR. Why this product solves common problems Accurate readings: the four-wire connection reduces measurement error caused by test lead resistance, making capacitance and ESR readings more reliable. Portable and flexible power options: built-in lithium battery plus Mini USB/DC5V input lets you use the device in the field or on the bench without constant external power. Easy calibration: the null key lets you zero out probe offsets quickly so measurements are not skewed by probe conditions. Faster troubleshooting: the ESR reference table helps you assess whether a capacitor is within expected ESR ranges, speeding up diagnosis. Important attributes Function: measures capacitance and ESR, supports loop power and loop testing through a four-wire socket, includes zeroing function for probe compensation. Power/compatibility: Mini USB interface and DC5V power input; internal lithium battery for portable use. Performance: four-wire measurement and zeroing reduce systematic errors and improve repeatability. Safety note: capacitors with high voltage must be discharged after testing. Limitations to be aware of The ESR reference table is for comparison only. Some capacitors may have ESR values outside the reference table range, restricting direct comparison for those parts. Always discharge high-voltage capacitors after testing to prevent injury or equipment damage. Typical applications / use scenarios Electronics repair and troubleshooting: quickly check motherboard, power supply, and audio circuit capacitors for elevated ESR or incorrect capacitance. Component evaluation during prototyping: compare candidate capacitors against the ESR reference table to select parts with appropriate ESR characteristics. Preventive maintenance: inspect electrolytic capacitors in power supplies and industrial equipment to identify weak components before failure. Quick operation tips Connect test leads using the four-wire socket for best accuracy. Press the zero (null) key to cancel probe offsets before measuring capacitance or ESR. Use Mini USB or DC5V to power or charge the internal lithium battery as needed. Discharge all high-voltage capacitors after testing.