HEKA PG 310, Руководство пользователя

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5. Operating Modes
The PG 500 is fundamentally an instrument for controlling cell potential
or current and measuring electric currents and potentials. In low current
ranges it uses a current-to-voltage (I-U) converter circuit to convert the
currents to an analog voltage, which is then made available at the current
monitor output for display or recording. In higher current ranges, a resistor
cascade replaces the I-U converter. In the potentiostatic mode, cell currents
are recorded at the same time while the potential is controlled. In the
galvanostatic mode, the current flowing through the cell is specified, and
the potential at the working electrode is recorded. The connection of the
electrochemical cell to the PG 500 potentiostat/ galvanostat is possible
in three different cell modes and can be controlled manually or by the
Potpulse
software.
ˆ
In the
Standby
mode, the cell is not connected to the
REFERENCE
and
COUNTER
electrodes; however the working electrode is always con-
nected to the cell.
ˆ
In the
OCP
(open cell potential) mode, the REFERENCE and
WORKING electrodes are connected to a measuring circuit with high
input impedance (see section Differential Amplifier below) for allow-
ing observation of the equilibrium potential (zero current potential).
ˆ
In the
Cell
mode, each of the three electrodes is connected to the
terminals of the potentiostat/galvanostat circuit.
Note: for any cell mode selection, the working electrode is con-
nected to the current amplifier.