Does your roof have different angles/orientations?
Does your system have modules on different tilts?
Does your system have different heights?
This article provides design recommendations to maximize the potential of your PV system.
TS4-O allows modules with different orientations or tilt angles to operate within the same string by reducing the impact of lower-producing modules on the rest of the string.
Modules receiving significantly less irradiance, such as east- and west-facing modules during different times of the day, may produce little or no power during periods of heavy shading. This is expected and does not prevent the remaining optimized modules from producing available power.
Note: Optimization cannot compensate for designs outside the electrical requirements of the TS4 or inverter. System performance also depends on the inverter's MPPT operation.
Follow the design and placement requirements below when using TS4-O with different module orientations or tilts.
TS4-O Design and Placement Requirements
1. Install TS4-O on modules that require optimization.
TS4-O does not need to be installed on every module in a single series string when only selected modules require optimization.
2. Use TS4-O and TS4-S in the same string
When monitoring and rapid shutdown are required across the entire array, TS4-O can be used on modules requiring optimization and TS4-S on the remaining modules.
This configuration can be used when:
- The string is connected to its own MPPT.
- No other string is connected in parallel to that MPPT.
- All modules in the string have the same tilt.
- All modules in the string have the same orientation.
TS4-S provides monitoring and rapid shutdown but does not provide optimization.
3. Use separate MPPTs for independent strings with different orientations or tilts when available.
Connect independent strings with different orientations or tilts to separate MPPTs when the inverter configuration allows it. Each MPPT can then independently track the operating point of its connected string.
For additional parallel-string requirements, see Design Considerations for Uneven Parallel Strings.
4. Parallel strings into single MPPT
If optimization is required on parallel strings sharing an MPPT, install TS4-O on every module connected to that MPPT.
5. Keep string voltage within the inverter operating limits.
Verify that string voltage remains within the inverter's MPPT operating range and maximum input voltage under expected site temperatures.
6. Each MPPT must receive sufficient voltage for the inverter to start and operate.
When modules within the same series string have different orientations or tilts, each orientation section must provide sufficient voltage to maintain inverter MPPT operation when the other section receives significantly less irradiance.
Conclusion:
PV modules with different orientations or tilt angles can be used with TS4-O when the system is designed within the electrical requirements of the inverter and PV modules.
Whenever possible, connect strings with significantly different orientations or tilts to separate MPPTs. If strings with different orientations must share an MPPT, install TS4-O on every module connected to that MPPT and follow the requirements in Design Considerations for Uneven Parallel Strings.
Each string or string section must provide sufficient voltage for the inverter MPPT to start and remain within its operating range under expected site conditions.
For assistance with your design, contact Tigo Sales Engineers: se@tigoenergy.com.
Additional Information:
How to Verify PV Module Compatibility with a TS4 MLPE
TS4 Compatibility with Bifacial PV Modules