
In late 2018 James Hoare from LHW Partnership contacted us to enquire more information about the new testing options offered by EmaZys. In early 2019 we shipped a Z200 PV Analyzer to James at LHW Partnership, and today James Hoare is using it in the field along with his arsenal of solar testing equipment. In this post we share some stories and insights from the field and we highlight the relevance, of fast and reliable solar array fault finding.
Z200 PV Analyzer - user profile
Name | James Hoare |
Title | CEng MIET MEI, Partner, CAA approved UAV pilot |
Company | LHW partnership LLP |
Relation | Z200 PV Analyzer costumer and super user |
Equipment | Z200 PV Analyzer, Solmetric IV Tester, Seaward PV150, EL/IR equipment for UAV |

Case study 1 and 2 are examples of field testing of solar PV. Case 1 is based on measuring various parameters, when 1 module in a string of modules, is shaded during measurements. This approach has the peculiarity that it can reveal faults such as PID and low shunting resistance, while still being rather simple to carry out. Testing a full string using this method can be done in 30 minutes and the result is a full insight into the health condition of each individual module.
In Case 2, the Z200 Analyzer “String Tester” was used to set up a series of measurements including solar module string impedance. The result is a fast overview of the general health state of the PV module string under test. The following was measured:
- Impedance curve – measured at VOC
- Open circuit voltage – VOC
- Short circuit current ISC
- Low frequency impedance norm – measured at VOC
- Low frequency impedance norm – measured during flow of PV system current
- PV system series resistance RS
- Isolation resistance RISO
- Estimated position of RISO
The final conclusion from Case 2 can be seen in the images below showing the impedance curve and the auto-generated Z200 PV Analyzer conclusion.




LHW Partnership is independent from any manufacturing and installation organisations, specialising in the provision of engineering services for the renewable and energy efficiency markets. They offer a full range of services for our customers both in the UK and overseas.
The LHW Partnership team is highly experienced within their fields and hold a vast amount of experience across different technologies including solar PV, wind, solar thermal, heat pumps, bioenergy and energy efficiency (ESOS approved lead assessor). With some of the leading inspection and test equipment available, we can undertake and resolve technical challenges that otherwise may go unresolved. LHW Partnership LLP is the only specialist renewable energy company in the UK with a CAA OSC UAV (drone) approval to fly with a reduced 20m area of control

