eDAQ Picostat, Руководство пользователя

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Chapter 2 — The Potentiostat 19
situations where oscillation is encountered (for example where large
surface area electrodes are being used in highly resistive solutions).
Do NOT use High Stability, when in Potentiostat mode, unless you first
encounter stability problems. High Stability decreases the bandwidth of
the of the Potentiostat control loop. Thus High Stability mode should
never be used when fast sweep rates (> 1 V/s), or when short term
pulses (< 0.1 s), are employed as it will produce a noticeable phase
lag between the desired and actual applied potential. Also
High Stability operation should not be used to try to correct for
oscillations introduced by excessive iR compensation.
High Stability operation can be used routinely when performing fixed
potential experiments with amperometric sensors where the response
time of the sensor is relatively slow (> 0.01 s).
It is likely you will need to use High Stability mode when in Galvanostat
mode, especially with highly resistive loads.
Note that High Stability operation is not required for either ZRA or
High Z operational modes, because the Potentiostat control loop is
disabled.
Current Signal Zero Point Calibration
The Calibrate button is available in Potentiostat and ZRA operating
modes,
page 15 . When the Calibrate button is clicked it corrects for
any internal offset error on the current signal. This is only required for
very accurate determination of signal values. Current accuracy will be
improved from about ±1% of full scale of range to better than ±0.2%. If
you do not need this accuracy then you do not need to use the
Calibrate button!
For best results allow about 10 minutes after opening powering up the
e-corder before using the Calibrate function. This allows the unit to
warm up — ambient temperature variation of more than a few degrees
during an experiment may require periodic recalibration to maintain
maximum accuracy.
When calibrating in ZRA mode you must first remove the Electrode
connector from the Potentiostat.