Application Notes/Articles

I-V Curves and Performance Verification

Building your array tree in Array NavigatorThe PV Analyzer user saves the I-V curve measurement of a PV string by just touching the corresponding branch of a graphical 'array tree.' This Application Note introduces a new feature in version 3.7 PVA software that lets you customize your array tree and name the layers to exactly match the engineering drawings. This improves the reliability of the measurement process in the field, and assures that the measurement results will be correctly labeled in your final report.

PV Analyzer Startup Training (Webinar slides)Slides from the expert training on how to effectively and safely use the PV Analyzer. Topics include PVA hardware and software, as well as PV module and system performance concepts. Voice-over version coming in June.

Interpreting I-V Curve Deviations (SolarPro reprint) Poor PV source performance hurts the bottom line. Fortunately, performance problems show up in the measured I-V curve. This article describes the six ways that measured I-V curves can deviate from normal curve shape, and provides an Array Troubleshooting Flowchart to help you identify the most likely causes.

Winning PV Contracts with I-V Curve Testing (app note) Performance testing tools and processes can be a differentiating factor for PV integrators and can communicate expectations of quality to suppliers and customers. This white paper provides language that you can use to your advantage in your proposals, including 1) a description of the business benefits of I-V curve tracing, and 2) contractual language specifying the use of I-V curve tracing.

Field Applications of I-V Curve Tracers (SolarPro Magazine) This article provides an excellent introduction to I-V curve tracers for use in commissioning, auditing and troubleshooting PV arrays.

Measuring I-V Curves in Harnessed PV Arrays (app note) Harnessing is a strategy for reducing the number of combiner boxes and associated feeder runs, as well as the number of string home run conductors, by paralleling strings upstream of the combiner. This note describes two strategies for setting up your Project in the PVA Analyzer software for measuring and evaluating the performance of harnessed arrays.

I-V Curve Tracing Exercises for the PV Training Lab (app note) This Application Note describes a series of outdoor PV training lab exercises that use the I-V curve tracer to show how PV arrays really work and how to troubleshoot problems down to the level of the individual PV module.

Guide to Interpreting I-V Curves (app note) Background on DC measurement techniques for testing I-V Curves of PV modules, strings, and arrays. Includes a description of ideal performance and effects of impairments, such as shading, series resistance, loose connections, etc. Also includes description of models that predict performance and comparison to measured results.

Photovoltaic Energy Production (Webinar slides)Introduction to PV systems in general as well as measurements associated with PV systems, including shade and solar access for site assessment and system verification with IV curves.

Checklist for Preparing to Test PV Arrays (app note) PV arrays can be tested very efficiently if the right preparations are in place. This checklist can help you get the most out of your time in the field.

Shade Measurements and PV Design

Best Practices for SunEye210 Shade Measurements (app note) Accurate estimates for solar production require accurate shade measurements. Getting accurate and consistent shade measurements requires the right tools and the right process for data collection and reporting. This document is intended to describe best practices in the measurement of shade, and to facilitate a common approach within an organization and across multiple organizations. It includes details about using the user interface of the SunEye-210 as well as the process for how and where to make the measurements on site.

Assuring Compass Accuracy in the Solmetric SunEye (app note) This app note will help you get the most out of your SunEye-210 compass.

Residential Solar Site Measurements: New Developments (SolarPro Magazine)This article addresses recent developments and trends in residential solar site measurements, including tools and best practices for measuring roof dimensions and shade, estimating system performance, and evaluating the impact of solar leasing options and performance guarantees on site measurement approaches.

Using Solmetric SunEye results in California’s solar electric incentive programs (app note) This application note describes the details of how to extract the SunEye data and input it to either the CSI Calculator or the NSHP Calculator. The Solmetric SunEye measures both solar access and obstruction elevation angles so it provides the data necessary for either calculator.

Understanding orientation issues in solar site analysis (app note)The Solmetric SunEye provides complete solar access and shade analysis in an integrated hand-held tool that can help optimize solar panel system design and installation. This note describes how to measure and account for orientation when using the SunEye.

Understanding the Solmetric SunEye (app note)A basic introduction to solar access and shade measurements using the Solmetric SunEye. Also included are descriptions of new features for measuring on metal roofs and with an extension kit.

Solar Site Evaluation: Tools and Techniques to Quantify and Optimize Production (SolarPro Magazine)Improve system performance and energy harvest projections with a thorough site evaluation that includes shading analysis and insolation quantification.

Align with Compass / Align with Target (app note)The normal way of aligning the SunEye is to align it using the compass to point South. "Align with Target" mode provides an alternative alignment to a reference azimuth using other visual information available at the site.