This installation tip was provided by Nick Soleil, product manager, Enphase Energy
While consumption monitoring is not a must-have for a typical PV installation, consumption data can help system owners better understand their energy usage. This information can help them evaluate whether or not adding storage makes sense.
When considering consumption monitoring for customers, installers first must determine if the split-core consumption CTs (current transformers) can be readily installed around the service conductors or busbars. If the consumption CTs cannot be easily installed on the service panel, additional electrical wiring may be required to prepare the site. To complete the site assessment, a qualified electrician may need to remove electrical enclosure covers. For Enphase installations, Enphase suggests following all safety and installation instructions in the Enphase Envoy S installation and operation manual. If the main electrical meter is installed in a separate enclosure from the main service panel, consumption CTs can probably be installed without any additional electrical wiring. Consider these questions:
- For installs with separate service and meter panels: Is the utility meter installed in an enclosure separate from the main electrical service panel? For installs with a combined service and meter panel: Is the utility meter installed in a combined meter or main service panel?
- Do both conductors in the main service panel have at least 2 in. of accessible length?
- If conductors are present, are they smaller than 350 MCM THWN, 350 MCM XHHW or 4/0 RHW? If busbars are present, are they thinner than 3/4 in.?
- Is there adequate space (3/4 in.) around each conductor/busbar to install the consumption CTs?
If you answered yes to all questions, the CTs can be readily installed without rewiring the service equipment.
If the service conductors or busbars are not readily accessible for the split core consumption CT installation or if paralleled conductors are feeding the main service, Enphase has additional tips and best practices online that allow for easy installation of the CTs.