Doing a solar install, my understanding is everything needs labeling and plan order labels via pvlabels, so the conduit needs labeling as well or just the boxes/disconnects etc?
Here in my US state, my inspector required the metal conduit indoors to have labels every 10 feet "Solar PV DC Circuit" or "Caution DC Circuit" (I am DC coupled).
Designed to meet solar system labeling requirements. All of our PV labels are UL Certified and printed on premium outdoor rated vinyl with 7 year permanent adhesive.