www.znshinesolar.com
Document No.
：
QES/ZX-RD-III032A
- 26
6.3
、
CLEANING
Dust accumulation on the glass surface of the module will reduce its power output and may cause hot spots.
So the surface of PV modules should be kept clean. Maintenance work should be performed at least once six
months or frequently.
Warning: It should be carried out by trained personnel. Workers should wear PPE, such as goggles, electric
insulation gloves and safety shoes. The gloves should withstand DC voltages of no less than 2000V.
Use dry or wet soft cloths, sponges, etc. to clean the modules during the cleaning process, but do not put any
modules directly into the water, do not use corrosive solvents and do not wipe the PV modules with hard objects.
When the pressure water is used, the water pressure on the glass surface of the module must not exceed 700
KPa. The module must not be subjected to additional external force. 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. If necessary, use isopropyl alcohol (IPA) or other solution
according to the safety instructions to clean and ensure that no solution flows into the gap between the edge of
the module and the module frame.
Clean PV modules when the irradiance is below 200W/m2. 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. For
example, do not use cold water to clean the module when the temperature of it is high during the day, otherwise
there will be the risk of module damage.
It is forbidden to clean PV modules under the weather conditions of wind more than 4 grades, heavy rain or
heavy snow.
When cleaning PV modules, Do not step on the modules; Do not spray 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.
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.
Do not scrape or grind stains off surfaces while PV modules are dry, as this can cause minor scratches on
the surface.
Water requirements when cleaning:
（
1
）
PH: 5
～
7
；
（
2
）
Chloride or salt content: 0 - 3000 mg/L
（
3
）
Turbidity: 0-30 NTU
（
4
）
Conductivity: 1500
～
3000 μs/cm
（
5
）
Total dissolved solids:
≤
1000 mg/L
（
6
）
Water hardness: 0-40 mg/L
（
7
）
Non-alkaline water must be used, and softened water can be used when conditions permitted.
