My system has a clear adhesive cover on top and it has become damaged. What can I do?

This article details how to replace the ambient brightness sensor (ABS) cover on Carmanah solar systems.

Product applicability

The following products are discussed in this article:

  • Legacy: R920, R247-E, and SC315
  • E Series: R920-E, R820-E, R829-E and R247-E
  • F Series: R920-F, R820-F, R829-F and R247-F
  • G Series: SC315-G, R820-G, R829-G and R247-G


Carmanah uses an ambient brightness sensor (ABS) located on the Energy Management System (EMS). Ambient light penetrates a hole in the solar engine or cabinet via a clear adhesive cover and feeds down a light pipe. The ABS detects this incoming ambient light level and adjusts the LED light intensity during the daytime and nighttime. Nighttime dimming, for example, is recommended by the MUTCD for flashing beacons (Section 4D.06, Paragraph 13), and required for RRFBs specifically (IA-21 5e).

If this cover becomes damaged or breaks, it can be replaced as a drop-in retrofit kit. It is recommended that the ABS cover is checked during routine preventative maintenance or any corrective maintenance that may take place.


Reference our technical bulletin for more detail on the release of our updated snap-in polycarbonate ABS cover from late 2019. This can be retrofitted into any of the systems above. All new systems will receive this updated cover from the factory.


Updated polycarbonate ABS cover

Please refer to the retrofit guide for installation instructions of the updated cover. See the video below for inspecting and replacing the ambient brightness sensor cover

See below for the various locations of the ABS cover across the different products:


E Series solar engine example with adhesive ABS cover on top center

Legacy R920/R247-E solar engines will look similar to the above image.


F Series solar engine example with adhesive ABS cover on the top left


SC315 (legacy) cabinet example with ABS cover on top right


G Series cabinet example with adhesive ABS cover on top right


Dual Energy Management System (EMS) versions of the SC315 or G Series cabinets will require two ABS retrofit covers.

Some G Series cabinets from 2018/2019 shipped with plastic sight glasses which should be as robust as the new polycarbonate cover. 

For systems that have been installed for several years, it is recommended to proactively change to the updated polycarbonate ABS cover during your next battery change or system inspection. You can order new covers in bulk from your distributor.