[RE-wrenches] best meters for array commissioning

[Jeff Yago]

In addition to designing and installing solar systems for all kinds of
clients since the 1980's, I am starting to receive requests from owners to
commissioning new solar installations that were designed and installed by
other firms.  In many cases these may have been installed by a large
commercial electrical contractor with no prior experience with solar
installations but was the installer for the rest of the wiring on the new
facility.  It is also possible that the engineer who designed all of the
electrical work on the new facility had no prior experience with solar
design, and just did a "cut and paste" outline spec using guidance from
suppliers providing the modules and inverters on the project. 

Since I am also a consulting engineer, I am sometimes asked to commission
new schools and hospitals, so I am very familiar with the "normal" LEED type
building commissioning process.  However, although I typically use a
voltmeter, ampmeter, and ground fault meter for commissioning my own solar
installations, I am thinking that to commission solar systems installed by
other firms (in some cases my competition) I better use one of the new
recording IV curve tracer test meters that would provide data recording for
documentation in case there was a later problem.

Since I do not need this level of system verification more than one or two
times per year, and the IV analyzers by Solmetric, Daystar, and Seaward are
very costly, its hard to justify the expense.  

Is anyone commissioning larger arrays using these "do-it-all" testing
devices, and which meter is easiest to use and best features for the $$.
Need s  something that can provide separate and combined IV curves for
multiple string arrays and save data files that I can convert to print back
in the office.  I would want a meter that is very easy to download the data
and print custom graphs without going through all kinds of data conversion
issues.

Any suggestions,

Jeff Yago