Appendix C: Grounding and Bonding

Tesla Zep Compatible™ systems do not require running copper conductors to each module. The act of physically installing each component simultaneously establishes an electrical bond.

Adjacent Tesla Zep Compatible™ module frames are bonded using two Tesla Solar products. The frame of every module is electrically bonded to adjacent modules and/or Array Skirts through the Interlock and Cam Foot. The frame of every module is part of the EGC path. The EGC path leaves the array by means of the Ground Zep connected to a copper conductor, which acts as the fault current path to ground. The face of the Ground Zep is labeled “GND.”

1 - Interlock

2 - Rockit (Cam Foot V2)

3 - Ground Zep "GND"

The following example shows a representative fault current ground path leaving a Tesla Zep Compatible™ array. Each Interlock and Cam Foot creates a bond between the module(s) and Array Skirt(s) it touches. The EGC path is carried through each module frame and Array Skirt. The fault current ground path then leaves the array through the Ground Zep. Typical Tesla Zep Compatible™ arrays will have multiple EGC paths, represented by the bond symbol below.

In the event a module must be removed for servicing, use additional Ground Zeps as needed to ensure the ground bonding path is maintained.

Interlock

Key Side Bonding to Module Frame

Forced interference during rotation of Interlock Zep causes teeth to cut through anodization on module frame, resulting in robust and UL certified bonding path.

Tongue Side Bonding to Module Frame

Forced interference between mating parts from module rock-in motion cuts into module frame for the range of allowable install positions, removing anodization and resulting in robust and UL certified bonding path.

Zep to Interlock Bonding

The rotating fastener attached to the Interlock plate, called the “Zep” or “Interlock Zep”, has two cutting teeth on the shaft that cut into the Interlock plate when the Zep is tightened during normal installation, resulting in robust and UL certified bonding path. The Interlock may be re-installed up to 15 times.

Zep in open position:

Zep in locked position cuts into Interlock plate.:

The Interlock bonds modules on all 4 sides and across the Interlock plate to create a hyper-bonded array where every module is structurally and electrically bonded to the surrounding modules.

Rockit

Key & Tongue Side Bonding

The Rockit has a stainless steel spring clip that bonds to the adjacent module frame on both Key and Tongue sides. A module can be pulled out to the edge of the lip and still be correctly installed, allowing for small variations in module sizes.

Cam Foot Bonding

The Cam Foot base has two cutting teeth that cut into the Spanner Bar when rotated.

Ground Zep

  1. Insert ground zep.

    The Ground Zep provides a single point of connection for the Equipment Grounding Conductor (EGC) from the array to a building ground. Insert a Ground Zep into the Zep Groove with the Set Screw pointing left.

  2. Lock ground zep.

    Using either a Zep Tool or the Flat Tool (shown), lock the Ground Zep into place with a 90 degree clockwise turn.

    The Set Screw should be pointing straight up.

  3. Insert ground wire.

    Insert solid copper ground wire into ground wire retention slot.

    To fully secure the ground wire, torque the set screw as follows:

    14-10 AWG: 40 inch-lbs

    8 AWG: 45 inch-lbs

    6 AWG: 50 inch-lbs

    4 AWG: 55 inch-lbs