POT/GAL
30 V/2 A
Electrochemical
Test Station

High Grade Potentiostat ­Galvanostat Systemfor Electrochemical
Impedance Spectroscopy
up to 1 MHz• Potentiostat ­ galvanostat system with superimpo­
sed frequency stimulus for electrochemical impe­
dance spectroscopy, cyclic voltammetry andtime domain characterisation• Unique solution for the precise characterisation ofboth conductive (i.e., high current) and insula­ting(i.e., low current) samples• Simultaneous measurement of dc voltages andcurrents at up to four electrodes• 2­, 3­ and 4­terminal configurations• High impedance differential voltage inputs withdriven shields• Operates in direct voltage mode as a high resolu­
tion impedance / dielectric analyzer• Precision gain phase measurements included

Novocontrol Technologies
GmbH & Co. KG
Aubachstr. 156410 Montabaur
Germany
Phone: +49 2602 9196690
Fax:+49 2602 91966933
e­mail: novo@novocontrol.de
web: http://www.novocontrol.de

Applications:• Battery Research• Corrosion• Coatings• General Electrochemistry• Dielectric andImpedanceSpectroscopy

NOVOCONTROLHigh Performance EIS
Novocontrol’s advanced modular Al­pha­A system features highest quality
broadband impedance and electricalmaterial measurements in the frequency
domain over an ultra wide impedance
range. It is widely accepted as the mostaccurate and versatile analysis tool for
dielectric, conductivity and impedance
spectroscopy and sets the benchmark
for overall performance and flexibility inthis area. In combination with a POT/GAL test interface, the same extraordin­
ary performance becomes available forelectrochemical applications, too. As aresult, almost all kinds of materials, i.e.,from the best isolators to metallic con­ductors, can be characterized by asingle powerful measurements system.
This is a significant improvement in instru­
mentation for electrochemical imped­
ance spectroscopy (EIS) compared toprevious designs that necessitate the useof several systems setups for the charac­
terisation of, e.g., strong electrolytes
which experience high currents and isol­ating materials with currents in the pA
range. In addition, typical electrochem­
ical experiments, e.g., cyclic voltam­
metry and DC measurements in the time
domain, are fully supported.

Components
For these purposes, POT/GAL extends
the Alpha­A mainframe by• a counter electrode poweramplifier,• a high input impedance referenceelectrodes differential input
amplifier,• a high accuracy working electrodecurrent input converter withreference technique,• a control loop for defined cell
polarization, potentiostat voltage
and galvanostat current,• a four channel digitizer for signal
measurements at 4 electrodes,• firmware for system control by highlevel remote commands.

Particular Features• Improves general performance of
EIS systems by high accuracy,
broadband and wide impedance
range performance.
• Supports higher harmonic measure­ments for non linear EIS both on in­strument and WinDETA application
software level.

POT/GAL 30 V/2 A
Principle of EIS

Key Specifications
POT/GAL 30V­2A + Alpha­AMainframe

Counter Electrode Polarization

A polarization voltage Udc, super­
imposed by a small ac voltage
Uac is applied to the sample. The
response current Is* and thevoltage Vref* across the electro­
chemical double layer capacity
are measured by amplitude andphase and thus the double layer
impedance Z*=Vref* / Is* is de­termined. In potentiostat or gal­vanostat mode, Udc iscontinuously adjusted in order tokeep the dc part of Vref or Is at adefined, i.e., constant level.

• High impedance (> 1 TΩ | 10 pF)
differential reference electrode vol­tage inputs for measurements ofisolating materials in 3­ and 4­elec­
trode configuration. User selectable
driven shield technology reduces
cable capacity effects.
• Direct control mode with disabled
potentiostat and galvanostat func­
tions as a high quality impedance
spectroscopy system with extended
voltage and current ranges.
• Automatic dc level shifters at theworking and reference electrode
inputs compensate dc voltage andcurrent offsets in order to accurate­
ly measure the small superimposedac signals for EIS.
• All system functions are controlled
by simple high level commands via
the Alpha­A mainframe GPIB port.
This feature allows easy integration
in your own software or combinati­
on with other automated equip­
ment like, e.g., temperature,pressure, or atmosphere control.
• As an additional protection of thesample, the high power counterelectrode signal output supports
additional fast voltage and current
limits which are independent of themain control loop. Both voltage
and current limits are continuously
adjustable and operate simulta­

Voltage: ±30 Vp dc and / or ac
resolution 1 mV dc, 20 µV ac
Current: ±2 A dc and / or dc
resolution ±1/32768 of current
range, 0.1 pA min.
Maximum output power: 60 W
Output Resistance:
1 Ω .. 1kΩ in factors of 10Bandwidth: dc .. 1 MHz
Continuously adjustable simultaneousvoltage and current limits:
1 V .. 40 V and 2 mA .. 2 ASupplies 2 A continuous current into a
shorted load without overheating.

Reference Voltage Inputs

Single or differential configuration
with selectable driven shields
Range: ±30 Vp, 20 µV resolution
Input impedance: > 1012 Ω | 10 pF
Bandwidth: dc .. 10 MHz

Working Electrode Current Input

Ranges 20 pA .. 2 A in factors of 10Resolution 10­5 of range,
0.1 pA min.
Bandwidth dc .. 10 MHz

Impedance Measurement

Frequency Range 3 µHz .. 1 MHz
Impedance range 10­4 Ω .. 1013 ΩPhase accuracy < 6m°tan(δ) accuracy < 10­4Phase resolution < 0.6m°tan(δ) resolution < 10­5Main Control Loop

Potentiostat, Galvanostat andDirect Voltage modes
Dc accuracy 1 mVTime constants 0.3 ms .. 3 s infactors of 3.33
Bandwidth dc .. 10 MHz
Electrolyte Rs compensation
Automatic Rs detection by highfrequency EIS, Rs compensationor correction
neously both in potentiostat and gal­vanostat mode.

• Supports real­time measurements of up
to 150 impedance data points per se­cond (option) and 1500 voltage­cur­rent data points per second in time
domain mode.