Date: April 14, 2020 Doc No: PS-M-0871 Ver: B Page 20 of 21
least once a year. Also, check that mounting hardware is properly torqued. Loose connections
will result in damage to the array.
9.3 CLEANING
The amount of electricity generated by a solar module is proportional to the amount of light
falling on it. A module with shaded cells will produce less energy and therefore it is important to
keep all PV modules clean.
Clean PV modules when the irradiance is below 200W/m2; liquid with a large temperature
difference from the modules must not be used for cleaning the modules;
It is forbidden to clean PV modules under the weather conditions of wind more than 4 grades,
heavy rain or heavy snow;
When cleaning with pressurized water, the water pressure on the glass surface of the module
must not exceed 700 KPa (14619.80psf); the module must Not bear the extra force;
When cleaning PV modules, do NOT step on the modules; do NOT spay water on the backside
of the module or the cables; keep the connectors clean and dry; prevent fire and electrical
shock from occurring; do NOT use as steam cleaner;
The back surface of the module normally does not need to be cleaned but, in the event this is
deemed necessary, avoid the use of any sharp projects that might damage the penetrating the
substrate material.
Periodically trim any vegetation which may shade the solar array thus impacting performance.
When cleaning the modules, use a soft cloth together with a mild detergent and clean water.
Take care to avoid severe thermal shocks which might damage the module by cleaning
modules with water which has a similar temperature to the modules being cleaned.
Use dry or wet soft clean cloth to clean the PV modules; non-corrosive solvents or hard objects
are strictly prohibited;
If there is greasy dirt and other substances on the surface of the PV module which are difficult
to clean, conventional household glass cleaning agents can be used; Do NOT use the alkaline
and strong acid solvents.
When cleaning the back surface of the module, take care to avoid penetrating the substrate
material. Modules that are mounted flat (0° tilt angle) should be cleaned more often, as they will
NOT ''self-clean'' as effectively as modules mounted at a 10° tilt or greater.
If you are unsure whether the array or section there of needs to be cleaned, first select an array
string that is particularly soiled, then
Measure & record the inverter feed in current from that string
o Clean all modules in the string
o Measure the inverter feed in current again and calculate the % improvement from cleaning
9.3.1 REQUIREMENTS FOR WATER QUALITY
PH: 5 ~7;
Chloride and Salinity：0 - 3,000 mg/L
Turbidity：0-30 NTU
Conductivity：1500~3000 μs/cm
Total dissolved solids (TDS)：≤1000 mg/L
Water Hardness—calcium and magnesium ions：0-40 mg/L
Non-alkaline water must be used; demineralized water shall be used if the condition permits.
9.3.2 MODULE INSPECTION AFTER CLEANING
Ensure that the module under visual inspection is clean, bright and free of stains;
Spot check to verify whether there is soot deposit on the module surface;
To Next Page
Loading...