ET Solar ET-P660250AC, Installation Manual

www.etsolar.com 

7 

Grounding in the AC Cables 

The AC cable attached to the microinverter and all accessory cables are fully insulated and 
contain an equipment grounding conductor (EGC). The full ground path from the transition 
cable to the module frame follows:   

•

The transition cable's green conductor is connected to the EGC from the utility dedicated 
branch circuit.   

•

All connectors have green ground contacts that are longer than the circuit contacts. This 
extra length ensures the ground is the first to make contact when connecting modules 
and the last to break contact when disconnecting modules. 

•

The AC ground wire inside the microinverter makes a bolted termination to the 
microinverter chassis and is environmentally sealed.   

•

The microinverter chassis is bonded at the factory to the module frame with stainless 
steel hardware to provide ground continuity to the AC PV module frame.   

The AC cable grounding path has been tested by a NRTL. Before an AC module assembly can 
be labeled with the NRTL certification mark and shipped from an authorized and inspected 
factory, each assembly must pass a ground continuity check to verify electrical continuity from 
the AC cable ground contact to the module frame. 

The AC cable provides equipment grounding for the AC module only. It is the installer's 
responsibility to ensure that any metallic parts in contact with the module (i.e. mounting 
systems) are provided with a means of equipment grounding according to the manufacturer’s 
instructions and local code.     

Because the DC power is internal to the module, a grounding electrode conductor (GEC) is not 
required.  

Because the AC modules are connected in a “daisy chain” fashion, disconnecting one module 
from within the string removes power and ground from subsequent modules in the string. 
Extreme care should be taken to ensure that no other energized sources are adjacent to these 
ungrounded modules, or auxiliary grounding methods must be provided.   

If a module is removed from within the string, it is recommended that you bridge 
the gap in the string using an AC extension cable. Inserting an extension cable 
maintains ground continuity to subsequent modules in the string. See "AC Wiring 
Accessories" on page 27 for a list of available extension cables. Other auxiliary 
grounding methods may be used.