What is ‘Green Zone’ clamping?

Clamping zones are the sections of the PV module that will be used to clamp the module to the racking using mid and end clamps. TerraGen racking is designed so that the mid and end clamps fall within the module manufacturers “green” zones. “Green” zone clamping refers to the section of the module where clamping will provide the most stability and best distribution of additional weight, such as snow.

Why is clamping in these zones important?

Clamping zones can vary from panel to panel. Many panels only have one type of clamping zone, which will be located around its mounting holes. Other panels can have multiple zones which will give an installer options on where to install clamps, depending on what conditions are like at a location.

Typically, the best place to clamp a module is on the long side in two locations near either end of the module, for a total of 4 clamps per module.

As you can see by the image above, there are green, yellow and red zones around the outer edge of the module. Green zones are the best possible option for clamping, followed by yellow and then red. Short side clamping is very common in landscape orientations, meaning that the module will be clamped in the yellow zone. Installers should be weary of this, and always ask the module manufacturer for their recommendation. Clamping outside of the recommended zones could result in voiding the module warranty.

What benefits does green zone clamping provide?

Green zone clamping provides the following benefits:

  • Equal weight distribution
  • Sufficient support for additional weight such as snow
  • Maintains module warranty
  • Reduced risk of advanced panel degradation and microcracks
  • System stability is enhanced

What are some of the risks of not clamping in the green zones?

  • Higher risk of panel damage
  • Module manufacturers warranty could be voided
  • Insufficient weight support
  • Reduced system stability

Next time you are installing commercial solar, be sure to double check the manufacturers clamping guidelines and make sure the racking system you have chosen is able to clamp using the guidelines.