STANDARD OPERATING PROCEDURE
String Inverter Installation – Zeverlution Series
Version 1.2 Effective date 02/08/2017
Page 3 of 15
INSTALLATION PROCEDURE
String Design Guidelines
To ensure efficient operation and compliance with the regulations, string design options are
limited. As per AS/NZS 5033 section 2.1.6, PV modules that are in the same string must have the
same tilt and azimuth angle within a tolerance of ±5°.
solarcity will determine which layout is most suitable based on a site visit prior to the installation. If
you find the provided layout to be unsuitable on the day of installation, please contact solarcity
immediately. The below section should provide a better understanding of our design guidelines.
As a solarcity installer or contractor, you are expected to report any possible discrepancies with
the below design guidelines immediately before you proceed with your work.
For both the Zeverlution 2000s and the Zeverlution 4000 inverters and for arrays with or without
optimisers the minimum and maximum strings lengths are as follows:
-
minimum
number of modules per string is
3
-
maximum
number of modules per string is
10
5.1.1
String Layout Without Optimisers
Where no optimisers are deployed, modules that are electrically connected as one string need to
be in the same orientation and tilt.
5.1.2
String Layout with Optimisers
The deployment of Tigo TS4-R-O optimisers allows modules in a single string to be installed as
split-arrays with different azimuth and/or tilt angles. As a general guideline, the main or most north
facing array must have a minimum of 3 modules to reach the inverters start up voltage and won’t
be optimized – while the “sub-array” will be optimized. Examples of array configurations and the
correct deployment of optimisers are shown below (with optimized modules shown in blue).
5.1.3
Shading
The benefit of optimisers in partially shaded arrays is insignificant. For solarZero systems, in some
instances, shading is mitigated by installing one additional module. solarcity will determine if this
is a suitable solution on a case by case basis.
