Our series “Solar Sightings” gives a behind the scenes look by highlighting case studies from the field.

Solar Technician’s Log 2022-04

SITE DESCRIPTION: 1.165 MWDC, Ground Mount

REGION: Midwest

FIELD FINDING: Improper wire

SOLUTION: Replacement of all DC wire

Get it Right the First Time

improper-wireDuring a third-party inspection, CES (Continental Energy Solutions) uncovered a major safety issue. The solar DC side was designed and installed as a 1000V system, which is common for C&I. However, the PV wire transitioned to nearly 20,000’ feet of THHN for the home runs. THHN transition is only rated for 600V, which is often seen on residential installs as a money saver for the installer. This “qualified contractor” installed improperly rated wire creating a fire hazard and passed local AHJ inspection. If the third-party inspection was performed during key times of the installation, the error could have been caught and repaired earlier – avoiding the safety risk and thousands of dollars of rework. 

Once again, CES 3rd Party Inspections saved the day! There were many other items flagged that the AHJ inspection did not discover. The installer was required to make all NEC revisions and process warranty claims for equipment discovered to not be operating correctly.  


Do not skip the crucial step of ensuring the work was done right the first time.  Third-party inspections provide ROI benefits that improve continuous system operation and prevent loss of production. Avert unexpected O&M costs and downtime by planning ahead. 

  • Catch Costly Mistakes
    Verify milestones of construction are met.  Installers that do not follow drawings, electrical codes, or best practices can cause thousands of dollars in system re-works. Problems can be identified at key times during the system rollout and a summary of findings with remedies to bring a project into compliance can be provided.
  • Prevent Safety Issues
    Inspections that look at NEC compliance avoid future system damage or disastrous conditions.
  • Ensure System Production
    A comprehensive review of system output and areas of loss of production.
  • Follow Best Practices
    Inspection Items that are not explicitly code violations but will ensure your system has reduced operational costs long into the future. 


Contact us for our expertise in handling a wide array of solar system problems with solutions that optimize systems for production and prevent downtime. From ground mounts to solar microgrid systems, we have your bottom line covered.

(630) 637-2150