Step 11. Install Energy Metering For The System - Tesla Powerwall 2 AC Installation Manual

Step 11. Install Energy Metering for the System

The placement of meters and current transformers (CTs) depends on the backup
configuration of the system (whole home or partial home) and whether the site includes solar
equipment. The Backup Gateway includes a pre-wired meter unit and one pre-installed CT.
The meter communicates with the Gateway over a pre-configured wireless connection.
NOTE: The meter antenna is required in all installations, including ones where the meter is
located inside the Gateway enclosure.
Current Transformer Placement
CT placement locations include the following:
Site (Grid) A CT is placed between the utility meter and main switch to measure both load and
generation.
Solar If the site includes solar equipment, a CT is placed after the solar inverter to measure the
solar output.
Load Site and solar metering are preferred. However, in configurations where it is not possible
to locate CTs between the utility meter and the main switch, load metering can substitute for
site metering.
Meter Placement and CT Wiring Lengths
CT leads are 1.5 m long and can be extended with 3 m extension kits (Tesla P/N 1125547-03-x),
depending on CT usage:
• Site/Load CT leads can be extended with up to one kit, to 4.5 m (15 ft). If the distance
between the Backup Gateway and the main panel is greater than 4.5 m (15 ft), the
meter can be removed from the Backup Gateway and relocated into the main panel.
When the meter is relocated into the main panel, use the antenna extension to place
the antenna on the outside of the panel.
• Solar CT leads can be extended with up to three kits, to 10.5 m (35 ft). If the distance
between the Backup Gateway and the solar equipment is greater than 10.5 m (35 ft),
use of a second meter for the solar equipment is recommended.
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