Aim TTi LCR400 Manual De Instrucciones página 12

External Bias
The 2 Volt DC bias available internally (see the Measurement Keys and Indicators section) is
usually adequate for polarizing electrolytic capacitors. However, it is possible to externally
connect a fully floating power supply (or battery) to give a bias voltage of up to 50 Volts DC.
The external DC bias must be connected to the LCR400 and DUT as shown in the diagram. The
High Drive, High Sense, Low Drive and Low Sense connections to the LCR400 are made using
the optional interface module which inserts into the Kelvin connectors on the top of the
instrument.
The BNC connectors on the interface module are marked with the signal names. Connect to the
power supply and DUT using screened cables, e.g. miniature coaxial cable, but leave the
screens unconnected at the remote end.
CAUTION. Always observe the correct polarity when connecting capacitors; failure to do so
may result in damage to the DUT and possible user injury.
Always discharge capacitors after making measurements with a DC bias, especially at high bias
voltages; failure to do so may result in possible user injury and damage to the LCR400 if the
charged capacitor is subsequently connected directly to the Kelvin connectors. The LCR400
has been designed to withstand the direct connection of capacitors charged up to 50V DC with
up to 1 Joule of stored energy ( ½ CV
such capacitors. Higher voltage or higher energy may result in damage to the instrument.
Inductors
All inductors have resistive losses, parasitic capacitance and an external coupled magnetic field.
The resistive losses are the resistance equivalent to losses in the core and the resistance of the
conductive wire making up the turns of the inductor. There is capacitance between each turn of
conductor and every other turn. The magnetic field of an inductor can extend outside the physical
package of the component.
In its simplest form the resistance can be represented as a resistor in series with the inductance,
and the capacitance as a capacitor in parallel. The effect of an inductor's self capacitance and
inductance at any given frequency combine to produce net inductance below the resonant
frequency or capacitance above the resonant frequency.
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); it should not, however, be used to routinely discharge
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