String inverter manufacturers often recommend that you do not mix different solar panels to a single MPPT on one string inverter. Instead, you can sometimes place different solar panels on separate MPPTs of the same string inverter, or on separate inverters altogether.

However, when using Tigo Energy TS4-A-O Optimizers, you may be able to connect different solar panels to a single MPPT on a string inverter, so as long as the solar panels are within 25% of each other's output. You can measure output at the solar array wire, or you can safely calculate the PV module mismatch by referring to Tigo Energy's article below.

Tigo Energy: Mix and Match Different PV Module Types

If you are using a Tigo Energy EI Inverter, you will also need a Tigo TAP. If you are using another brand inverter, you will need a Tigo CCA, a TAP, and possibly an RSS Transmitter. To determine which inverters are compatible with Tigo's optimizers, refer to Tigo's resource link below.

Tigo Energy: UL PVRSS certified inverters with Tigo