Megger LTW425 Loop Impedance Tester

The Megger LTW425 Loop Impedance Tester is a two-wire + maxZ + (R1+R2) earth loop tester which verifies the loop impedance of a live electrical circuit, i.e. without the need to disconnect the electrical supply.

The Megger LTW425 Loop Impedance Tester uses a 2-wire loop testing solution that does not trip 30 mA RCDs.

The Megger LTW425 Loop Impedance Tester will operate on a wide range of voltages from 50 V AC to 300 V AC single phase supplies and up to 440V AC on 3 phase installations.  This includes centre tapped 110 V AC circuits, with 55 V phase to earth.

A loop test is performed with only 2 test leads. This can be either:

• Phase to Earth
• Phase to Neutral
• Phase to Phase

Testing is simple, as there is no need for a 3rd wire to be connected, which can cause confusion when trying to identify which part of the circuit is being tested.

The Megger LTW425 Loop Impedance Tester offers a high current high-resolution loop test to three decimal places.  This is ideal for establishing the correct Ze on an incoming supply, especially on PME installations.  Results of this test can also be used to calculate higher PFC results. 

It can calculate up to 40 kA using the 0.001 Ω high current, resolution test range.  The calculation uses the measured loop impedance and the measured line voltage to calculate the appropriate PFC.

Megger LTW425 Loop Impedance Tester features:

• 2 Wire Non-tripping loop testing
• 2 Wire fast test (high current)
• 50 V to 440 V applications
• Phase to phase testing
• 20 kA PFC
• 40 kA PFC
• CATIV installation testing
• AUTO start loop
• AUTO noise detection
• Voltage measurement
• Frequency measurement
• 0.01 Ω resolution
• 0.001 Ω resolution
• Max Zs display
• R1 + R2 display

Megger LTW425 Loop Impedance Tester comes complete with a calibration Certificate Traceable to National Standards when purchased new.

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