18. June 2026

Troubleshooting Potentiostats: Systematically Isolating Sources of Error

When a potentiostat does not control as expected, a defect in the device is often suspected first. In practice, however, the cause is frequently located elsewhere. Problems particularly often arise in the electrochemical setup, in the potential measurement path, at the electrode connections, or due to damaged cell cables.

Potentiostats are robust control amplifiers. They are designed for demanding laboratory applications and, in many cases, tolerate unfavorable operating conditions or faulty wiring. This makes a structured troubleshooting process all the more important. With a few targeted checks, it is usually possible to quickly determine whether the error lies in the device, the cell setup, or the cabling.

This article demonstrates how users can proceed systematically when troubleshooting potentiostats.

If the potentiostat does not control: check the cell setup first

Conspicuous measurement behavior does not automatically mean that the potentiostat is defective. The cause is often found in the external control loop. Interruptions or unstable contacts in the potential measurement path are particularly critical.

Typical sources of error include:

Interruptions in the potential measurement path
Problems with the Haber-Luggin capillary or salt bridge
Gas bubbles in the area of the potential measurement
Loose or damaged electrode connections
Cable breaks or loose connections in the cell cables
Faulty contacting of the electrodes

In electrochemical measurements especially, small disturbances can have significant effects. A gas bubble in the wrong place, a damaged cable, or an unstable contact can result in reliable potentiostatic control no longer being possible.

Using a dummy cell: checking the basic function of the potentiostat

A proven first step is testing with an equivalent cell circuit, also known as a dummy cell. This allows you to determine whether the potentiostat is fundamentally working correctly.

Testing procedure

Set the target voltage to 1 V.
Set the current range to 1 mA.
Set the operating mode to potentiostatic control.
Gradually reduce the target voltage.
Check whether the measuring instrument displays correspondingly lower values.

If the dummy cell reacts as expected, the potentiostat is fundamentally functional. In this case, the cause is very likely not in the device itself, but in the actual measuring cell, the reference electrode, the potential measurement path, or the cabling.

The dummy cell is therefore an important tool for distinguishing between device errors and cell setup issues.

Checking the reference electrode and potential measurement path

If the dummy cell works correctly but the actual cell cannot be controlled, the potential measurement path should be specifically checked. A frequent source of error is the reference electrode in conjunction with the Haber-Luggin capillary or salt bridge.

One way to isolate the problem is to temporarily replace the reference electrode, including the Haber-Luggin capillary, with a metal wire immersed directly into the cell. This allows you to check whether the cell is fundamentally controllable potentiostatically.

It is important to note: The potential of this provisional “reference electrode” may be shifted compared to the previously used reference electrode. The test is therefore not intended for exact measurement evaluation, but for error isolation.

If control is possible with this test setup, there is a strong indication that the original reference electrode, the capillary, the salt bridge, or the contact with the measurement solution is the cause of the problem.

Checking cell cables and electrode connections

If stable control is still not possible even with simplified potential measurement, the cell cables and electrode connections should be checked. A purely visual inspection is often insufficient. Cable breaks or loose connections often only become apparent under mechanical movement.

A useful inspection includes:

Continuity testing of the cell cables
Moving, bending, and stretching the cables during measurement
Checking the plug contacts
Checking the electrode connections
Visual inspection for kinks, damaged insulation, or loose contacts

Testing under movement is particularly important. A cable may appear inconspicuous at rest and yet lose contact under slight stress. Such interruptions can strongly influence the control and lead to seemingly implausible measurement results.

Changing the current range and checking the range switch

If the dummy cell does not work correctly, the test should be repeated in a different current range. To do this, change the current range at the range switch and perform the functional test again.

It should be noted that the deflection on the measuring instrument in a different current range does not have to correspond exactly to the behavior described previously. The decisive factor is whether the potentiostat reacts at all.

If the device reacts in a different current range, this may indicate a defective range resistor. In this case, the device should be professionally inspected.

When a device error is likely

A serious device error is only likely if several checks are negative:

The dummy cell does not work correctly.
The test remains conspicuous even after changing the current range.
Cell cables and electrode connections have been checked.
The potential measurement path has been ruled out as a source of error.
Even simplified test setups do not lead to stable control.

In this case, the potentiostat should no longer be used in the regular testing process. A professional inspection helps to avoid consequential damage, incorrect measurements, and unnecessary downtime.

Troubleshooting Potentiostats: Key Points at a Glance

Conspicuous control behavior does not automatically mean that the potentiostat is defective.
Common causes lie in the potential measurement path, at the reference electrode, or in the cabling.
The basic function of the potentiostat can be quickly checked using a dummy cell.
Loose connections often only appear when cables are moved during the continuity test.
If all tests are negative, the device should be professionally inspected.

PSL Labtec provides support for diagnosis, service, and calibration

Structured troubleshooting saves time and helps to avoid unnecessary device returns. At the same time, there are cases in which a professional inspection of the potentiostat is useful or required.

PSL Labtec supports users with the diagnosis, service, and calibration of potentiostats. If the described tests do not show a clear cause or a device error is suspected, the system should be inspected.

Do you have questions about troubleshooting, calibration, or the service of your potentiostats?

Then contact PSL Labtec. The service team will support you in further isolating and testing your device.