SMA new module level RSS add-on vs older controller and switch button


Senior Member
Trying to meet Rapid Shutdown requirements with an SMA inverter on a residential job.
What is your experience with the new SMA module-level add-ons (TS4-R-O and TS4-R-F) .......vs older RSS controller and switch button?

First option seems simpler to install, and cheaper too. I heard they have poor reliability. Is that true?
Is the second option available still?
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Senior Member
TS-R-O is interesting but I would stay away, because that may be where the poor reliability comments stem from as it requires an external communication interface that may be subject to field installation issues. I have been bothering the Tigo rep with questions so I'll post what I know about it here. There are a few different models with similar functionality:

TS4-F - Module Integrated
TS4-R-F - Retrofit kit that snaps onto frame
TS4-A-F - 'Advanced' which snaps onto just one side of the frame and is the newest product.
TS4-A-2F - Same but works for 2 modules

Each of these does not require any communication interface like some of their other products do, other than a power line communicator transmitter.

Make sure you install a UL listed rapid shutdown transmitter or one of the listed compatible inverters with an integrated transmitter.

Bear in mind the type of connectors that are included are: MC4, EVO2, and PV-ZH202B (MC4 comparable)

Here are the compatibility declarations by both companies:

Hope this helps,


Senior Member
The old system is not NEC 2017 compliant where the new system with the TS4s is. If you are on the 2014 NEC you can still use the old system, it did the job.