To Next Page

To Previous Page

Charging is performed automatically when the AC/DC adapter is connected. The FRAX-101 does not have to

be turned on. To ensure long battery life, batteries will not be charged if the battery charge is higher than

90 % or if the temperature is above 40 °C. A complete charge takes approximately 8 hours.

The blue LED gives indication of charging status:

LED not lit FRAX turned o, or FRAX is switch-

ed on, battery empty.

LED blinking Charging

LED lit FRAX connected to AC/DC adapter,

Battery is fully charged (or charging

disabled of other reason see above)

LED lit FRAX runs on batteries (AC/DC

adapter not connected)

3.5. Ground loop detector

Embedded ‘Ground Loop Detector’ in FRAX checks the test setup and assures that all connections including

the grounding braids are properly connected. After pressing GLD button on FRAX the green/ red (“Pass/

Fail”) LED shows user status of the ground loop. In case of ‘’Fail’’ signal (red LED), the connections must be

checked. “Pass” signal (green LED) guarantees that the measurement results can be reproducible.

NOTE

Ground loop detector is not available in FRAX 99.

3.6. Sweep frequency response

FRAX “Generator” (Gen.) output generates sinusoidal voltage at a selected frequency. Two separate input

channels, “Reference” (Ref.) and “Measure” (Meas.) measure both the generated voltage and the response

voltage with respect to amplitude and phase.

The instrument stores “Amplitude” and “Phase” data for both “Reference” channel and “Measure” channel as

well as the ratio “Measure” divided by “Reference”. The values can be plotted and exported as Magnitude,

Phase, Impedance, Impedance-Phase, Admittance and more.

The Custom models function make it possible to calculate almost any parameter based on the measured/

stored data.

FRAX uses the sine correlation technique. This means that the input voltages are multiplied by a sine and a

cosine, and then averaged over an integer multiple of the interval of time. The sine, cosine and the voltage

applied have exactly the same frequency. The sine correlation technique is well known and is suitable for

Sweep Frequency Response Analysis (SFRA) measurements. Since the signals on the two input channels are

treated the same way, the phase resolution between these two channels is extremely high. The rejection

of DC oset and harmonics - referred to as the applied voltage - are in theory innite. By increasing the

integration cycles, the rejection gradually improves.

Instrument description

Megger FRAX Series User Manual

Questions and Answers: