Maintenance - Weidmuller Annex Bedienungsanleitung

5. Maintenance

This combiner box is a maintenance-free device. However, the following visual
inspections should be made annually. Maintenance of a PV combiner box must be
performed by qualified personnel and using the right tools and protections.
• Check seals
– Since the strong temperature fluctuations outdoors place a heavy load on the
seals, you must ensure by means of visual inspection that the cover seals have not
perished.
– Check the seals and screw connections as well as the ventilation and drainage
inserts.
– Check and retighten if needed the cable glands according to the torques that can
be found in the annex.
• Check the surge arresters. Check whether the inspection windows on the optional
surge arresters are showing "green". Surge arresters showing "red" must be
replaced.
• Check fuses. We recommend checking the fuses for continuity since blown fuses
diminish yield of the PV plant.
CAUTION
Do not open fuse disconnectors under load (the DC switch must be
open first). Before opening a fuse-disconnector make sure there
is no reverse current flowing into the corresponding string. Before
closing a fuse-disconnector make sure the open circuit voltage of the
corresponding string is not very different from the rest.
• In AC combiner boxes with residual current device (RCD or RCBO) it is
recommended to test-trip it monthly.
• Check tightening torques and retighten to the correct torque if needed.
• If your product has ventilation grids with a filter, check the status of this filter and
replace it if needed.
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Order Number: 7791700275 · Ed. 4 · 04-2016