Current Transformer Capacity

Standard Neurio CTs have a capacity of 200 A.

If the wiring configuration allows, it is possible to pass multiple conductors of the same type through a single CT, provided the sum of the conductor’s current ratings does not exceed the CT current handling capacity. This is especially useful for systems with multiple solar inverters.

Note

Multiple conductors through a single CT is only possible if all conductors are on the same phase.

Figure 1. Multiple Conductors Passing Through Single Neurio W1 CTs

If a site has multiple solar inverters spaced far apart, or if a main panel has two main breakers (for example, 400 A service with two 200 A breakers), a Y-splitter cable (for Neurio W1 meters: Tesla P/N 1129625-00-x, for Neurio W2 meters: Tesla P/N 1622286-xx-y) can be used to connect two CTs on the same phase to a single meter port.

Figure 2. Y-Cables Connecting Neurio W2 CTs on the Same Phase

For the Neurio W1 meter, 800 A CTs are also available for larger service sizes (Tesla P/N 1447689-00-x). The 800 A CTs can only be used with the Neurio W1 meter, and the 800 A CT option must be selected during device setup from a drop down menu on the Meter page.

Note

When 200 A CTs are used in parallel, each input channel can measure up to 400 A. When 800 A CTs are used in parallel, each input channel can measure up to 1100 A.