Install Cts For Metering - enphase ENV-S-WM230 Installation And Operation Manual

3. Install CTs for Metering

The Envoy-S Metered (ENV-S-WM-230) uses terminal blocks for power and metering connections.
When wiring the Envoy-S for production and consumption metering, be sure to install the
NOTES:
current transformers (CTs) exactly as described for your application.
When using CTs, do not energise the PV system before the CT installation is complete.
Do not install the CTs in a panel where they exceed 75% of the wiring space of any cross-
sectional area within the panel, or refer to local standards for guidance.
You can run more than one wire through the CT if all wires are on the same phase and they
fit the opening in the CT.
Install one split-core CT (model CT-100-SPLIT) per monitored phase for production metering and one
split-core CT (model CT-100-SPLIT) per monitored phase for consumption metering. Use a protected
route in conduit (raceway) for the CT wires to the Envoy-S. If you need to extend the leads (up to 148
meters, see "Extend CT Leads, If Needed" on page 16.
Preparation
a. Before running the CT wires through conduit, use coloured tape to mark each of the CTs and the
free ends of its wires, marking each with a different colour. You can run multiple CT wires
through a single conduit.
b. When installing CTs, it is important to match CT and voltage sense phases. Be sure to
consistently identify all the AC lines at three points: the main switchboard feed, the Envoy, and
the solar production circuit breaker. Wire colours may not always consistently identify Lines 1, 2
and 3. If in doubt, use a multimeter to check.
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Envoy-S Metered Multiphase Installation and Operation
© 2016 Enphase Energy Inc. 141-00035 Rev 01