Eaton SEFELEC 1500M, Руководство пользователя

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SEFELEC1500M Instructions 85 V1.06
10.2. PRECAUTIONS TO OBSERVE DURING A MEASUREMENT:
To take a current measurement less than the µA, use an effective shielding connected to the
guard terminal (grey terminal on the front panel for a floating measurement or ground terminal
on the rear panel for a measurement with the guard connected to the ground). Erroneous meas-
urements due to the presence of parasitic leakage currents or to introductions of mains fields are
as such prevented.
The proximity of an operator bringing his hand close to the tested sample can distort the meas-
urement. Care should be taken not to wear nylon lab coats or insulating objects which may cre-
ate high static electricity fields which could affect the operation of the device at very low current
levels.
A measurement of 10 Teraohm under 10 volts corresponds to a measurement of a current of
1 pA.
When measuring capacitive circuits (use the CABLE or CAPACITOR mode, see chapter 9-4)
never take measurements by decreasing the measuring voltage at each test but always by in-
creasing it; the phenomena of hysteresis and polarisation presented by the dielectric would
distort the results. In this case the device will tend to indicate the maximum and will take a long
time to fall to the real value to be measured.
Never disconnect a capacitive sample without switching to DISCHARGE and waiting for the
time requi
red for the capacitance of the sample to discharge into the 2.2 kΩ resistor of the
discharge circuit.
After connecting the component to be measured with the precautions described hereinabove
and selecting the required measuring parameters, return to the measuring screen hereinbelow: