Electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current (AC) circuit. Impedance extends the concept of resistance to AC circuits, and possesses both magnitude and phase, unlike resistance, which has only magnitude. When a circuit is driven with direct current (DC), there is no distinction between impedance and resistance; the latter can be thought of as impedance with zero phase angle.
Custom microprocessor controlled for highest accuracy and reliability. • 3 LEDs for checking correct wiring status. • 15mA LOOP measurement:LOOP impedance 2000Ω range measurement is carried out with low test current (15mA).The current will not cause tripping out involved RCD even the one with the lowest nominal differential current (30mA). • Direct reading of Prospective Short Circuit Current (PSC). • Safe voltage measurement function. • Large custom digital display readout on all models. • Measure low loop resistances(resolution of 0.01Ω) • Automatic lock-out if test resister overheats. • Large custom digital display readout . • Visual indication of reversed phase and neutral wiring at socket. • Designed to IP54 Rating • Complies with IEC 61557
• Anti-Trip Technology for complete trip free Loop testing on all RCDs rated 30mA and above. • Dual Display allows simultaneous measurements like Loop & PFC/PSC. • Two wire connection for Loop L-L, L-N and PSC testing is possible. • Phase rotation, Voltage and Frequency measurements. • Lock-down test button for 'hands free' testing with auto-start operation. • Display and front panel keyboards with Backlight to be visible in dark places. • Water and Dust proof (IP54)
Kew Combitester provides the ultimate in Microprocessor technology offering Loop and RCD tests with a comprehensive memory and downloading test results. • LOOP Impedance 200/2000Ω range measurement is carried out using a test current of 15mA. This current will not trip RCD’s rated at 30mA or greater. • High resolution for low Loop Impedance (resolution of 0.01Ω) on 20Ω range. • Direct reading of Prospective Short Circuit Current (PSC) and earth fault current.