Gamry Interface 5000, Руководство оператора

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Appendix A: Interface 5000 Specifications
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2. Measured with a high-power 1

load resistor connected between the counter and working electrode
leads, in potentiostatic mode.
3. Unity gain bandwidth and slew rate are correlated. Each has five settings, with the highest slew rate
occurring at the highest bandwidth, down to the lowest slew rate occurring at lowest bandwidth. Both are
measured with 2 k
 between counter and reference, and 20  between the reference and the working
and working sense leads.
Measured with a Frequency Response Analyzer connected to the Ext Sig In pins of the
Monitor connector.
4. Measured with an external function generator connected to the Ext Sig In pins of the Monitor connector.
Cell resistor 90
Ω
connected between the counter and working electrode leads, in potentiostatic mode.
5. The A/D and signal-processing chain in the Interface 5000 allows measurement of voltage signals as large as
±
6.5536 V. The voltage on the Work Sense lead can be as high as
±
0.51 V when measuring 5A using a 60
cm cell cable. This implies a maximum voltage input on the differential electrometer of
±6.04 V.
6. This specification is tested using a 2 G

resistor switched into the input and measuring the voltage
difference with and without the input resistance.
7. The differential impedance is measured between the Reference and Work Sense inputs. This is the
impedance you measure when you record the EIS spectrum of an infinite impedance (open lead) cell.
There is also a common-mode resistance and capacitance associated with the differential electrometer
inputs. These values tell you how much the electrometer response is modified by a resistance in series with
the source.
8. The bandwidth is for a sine-wave source with a 50 Ω output impedance driving either input. The
bandwidth is well in excess of this specification, which is limited by the measurement equipment used in
routine testing of the Interface 5000.
9. CMRR is common-mode rejection ratio. It specifies the ability of the differential electrometer to reject
signals connected to both inputs. The CMRR is measured driving both inputs with a sine-wave source with
a 50
Ω output impedance, and measuring the error as a function of frequency. Resistance in either input
will cause a loss of CMRR.
10. Voltage measurement is performed with a nominal  6 V signal input to the ADC signal chain. The actual
full scale is 6.5536 V.
11. The total error in a voltage measurement is:
Error = Zero Offset Error + Gain Error × Voltage
For a 1 V signal the theoretical error can be as high as 2.5 mV. This error is typically less than 0.2 mV.
12. Offsets are summed into the signal. Offset inaccuracy is approximately
±
0.05% of the setting plus
±
0.5
mV.
13. There are six hardware current ranges, separated in sensitivity by decades. The ranges are 50 µ

A, 500 µA,
5 mA, 50 mA, 500 mA and 5 A full scale. The ×10 and ×100 gains add two virtual ranges of 5

A and 500
nA full scale.
14. The voltage across the current measurement resistor, R
m
, is as shown. On ranges below 5 mA, the working
electrode voltage is similar to the voltage across R
m
. At 5 A and 1 MHz, the working electrode voltage can
be as high as 0.51 V, because the cable has both resistive and inductive impedance.
15. The total error in a current measurement is:
Error = Input Current Range Zero Offset × FS C Gain Tolerance × Measured Current
The first term can generally be ignored on the Interface 5000. The units for the error are amperes.
16. Drift can be approximated by simple drift in the Range Zero Error. In reality all three terms in the equation
above can have drift.
17. The Current to Voltage converter bandwidth is a function of the current range, the cell cable, and the
IEStability setting. Longer cell cables add capacitance and slow the current measurement.
The specified I/E Converter BW is measured at 5 mA I/E Range.