LHW Partnership

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.

EmaZys LHW Partnership
LHW Partnership solar testing

Case studies 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 the 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.

Z200 PV Analyzer impedance curve – download test results form Case 2 for the full report.
James LHW 2
Testing in the field with the Z200 PV Analyzer. Often the technician must connect at the inverter or combiner box. In this case it can be practical to bring and chair and thoroughly collect the desired data.
James Hoare LHW
The Z200 PV Analyzer is connected directly on the DC side of the PV system and from here testing and troubleshooting takes place. The instrument is operated over Wifi using e.g. a smartpåhone or (as here) a mac computer.

LHW Partnership is independent of any manufacturing and installation organizations, specializing 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 holds 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