Wiring - General

 

 

Chassis Ground

The chassis ground is a copper bus bar in the Main Inverter Enclosure and has

 

3/8-16" bolts for terminating the AC ground. The ground conductor size depends

 

on the size of the main circuit breaker.

 

NEC Table 250.122 (Ninth Edition) requires that the ground conductor be at least

 

#3 AWG for a 400 A circuit breaker and #6 AWG for a 200 A circuit breaker.

Torque connections to ground bar in the Main Inverter Enclosure as follows:

PV100S-208 - 420 in-lbs (47.5 Nm)

PV100S-480 - 420 in-lbs (47.5 Nm)

The equipment ground on the PV100S is marked with this symbol:

AC Ground Bar (TB1) to be used for the Chassis Ground

 

Main Inverter Enclosure

 

Figure 3-11Chassis Ground Bar (TB1)

Array Grounding

NEC Article 690-41/42 (Ninth Edition) requires the PV array to be earth

 

grounded. The PV100S chassis is also bonded to the PV safety ground terminal

 

block.

System Neutral Requirements

The PV100S is designed to be installed as a 4-wire system. As required by the UL 1741 listing, a neutral conductor from the utility-interconnect must be terminated at TB6 within the AC Interface Enclosure to ensure that the AC voltage sensing circuit can perform an individual phase voltage (line-to-neutral) measurement. The function of the neutral connection is to provide a point of reference for measurement purposes that is essentially at ground potential. No power will flow through the neutral conductor.

Utility Side Isolation Transformer Requirements

The PV100S is supplied with a custom, high-efficiency, isolation transformer as part of the AC interface/transformer assembly. The utility side windings of the isolation transformer are configured Wye and must match the voltage at the utility

152315 Rev C

3–13

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Xantrex Technology PV100S-480 System Neutral Requirements, Utility Side Isolation Transformer Requirements