MAJ K4118

SKU: MAJ K4118

BRAND: Major Tech

300V Microprocessor Controlled IP54 Loop Impedance and PSC Tester with Distribution board test leads



The K4118 instrument is microprocessor-controlled and includes useful features such as mains voltage measurements, neon indication of current wiring status and a lock down test button for hands-free operation.

An added feature is a 200 ohm earth electrode resistance test range to check that the earth electrodes comply with the IEC wiring regulations. The Major Tech K4118 Digital Earth Loop Impedance Testers is the most technologically advanced series of such instruments available and are designed to comply with IEC 61557-1 regulations.

This instrument offers convenient and accurate measurements of Earth Loop Impedance at the origin (Ze) and at various points throughout the electrical installation (Zs).

The K4118 offers three pre-selectable Loop Impedance ranges and three pre-selectable Prospective Short Circuit (PSC) ranges.

When the external earth probe is utilised, it is possible to measure the phase to Earth Loop Impedance of exposed metalwork, such as light fittings, trunking and where applicable conduit.



  • Microprocessor Controlled for Accuracy and Reliability
  • Automatic Lock-Out if Test Resistor Overheats
  • Direct readout of Prospective Short Circuit Current and Earth Fault Current
  • Lock Down Test Button for Continuous use
  • Measures low loop impedance of 0.01Ω
  • 3 LED’s for checking correct wiring status
  • External earth probe option
  • Displays mains voltage
  • Visual identification of reversed phase and neutral wiring at socket
  • Supplied with distribution board test leads
  • IP54 Casing



  • Dimensions : 186x167x89 mm
  • Weight : 750g
  • Reference Conditions
  • Ambient temperature: 23 ± 5°C
  • Relative humidity 45% to 75%
  • Position: horizontal
  • AC power source 230V, 50Hz
  • Altitude up to 2000m
  • Operating Temperature and Humidity : 0 to +40°C, relative humidity 80% or less, no condensation
  • Storage Temperature and Humidity : -20 to +60°C relative humidity 75% or less, no condensation
  • Symbols used on the instrument : Equipment protected throughout by double insulation or reinforced insulation.


Loop Impedance
  • 20Ω (25A/20ms) : ±(2%rdg +4 dgts)
  • 200Ω (2.3A/40ms) : ±(2%rdg +4 dgts)
  • 2000Ω (15mA/280ms) : ±(2%rdg +4 dgts)
Prospective Short-Circuit Current
  • 200A (2.3A/40ms) : Consider accuracy of Loop Impedance
  • 2000A (25A/20ms) : Consider accuracy of Loop Impedance
  • 20KA (25A/20ms) : Consider accuracy of Loop Impedance
Measuring Range
  • 110 ~ 260V : ±(2% + 4 dgts)