What Should You Check in Spring for Solar Panels | Damage, Wiring Cleanliness

Spring season should check modules whether crack, wiring loose, clear dust pollen (can raise power generation 5–10%); detect inverter and voltage current whether normal, suggest every quarter patrol inspect one time and record power generation data compare.

Damage

Look glass

Experience finish one winter average thickness reach 15 centimeters's accumulate snow cover, every piece area about 1.9 square meters's solar energy panel bears static load often break through 5400 pascals. This kind of continuous physical oppression for three months's will let the thickness only be 3.2 millimeters's photovoltaic tempered glass produce stress fatigue.

You can at 10 o'clock in the morning, light illuminance at 600W/m²'s environment under, take a handle output brightness is 1000 lumens's LED flashlight, stick glass surface with 15 degrees angle parallel shine. Careful observe the glass surface, it has not have width exceeding 0.05 millimeters, length greater than 3 centimeters's white color flocculent line strip. The photovoltaic panel's monocrystalline silicon wafer's thickness is only 160 micrometers, and the glass surface's tiny shape change will according to 1:1's proportion conduct down direction's silicon wafer, form micro level's physical break break. Panel on statistic to 3 strips above length exceed 5 centimeters's crack, this module's effective light transmission rate will from out factory's 94% drop down to 89% below.

Moisture will follow 0.05 millimeters's crack penetrate enter, with internal thickness 0.4 millimeters's EVA package glue film happen chemical reaction, lead to original transparent's glue film in 60 days inside appear area account proportion exceed 15%'s yellow transform phenomenon. This kind of yellow transform will block wave lengths at 400 nanometers to 1100 nanometers in the available light spectrum, let single piece 400W rated power's panel in standard test condition (STC, environment temperature 25℃, light shine intensity 1,000 W/m²) 's down's actual output power drop to 360 W below, year average power decay rate from normal's 0.55% soar rise to 3.2%.

· Prepare an enlarged multiplier is 10 times's portable enlarge glass, check look panel edge 3 centimeters range inside's silica gel seal strip.

· Measure seal strip's dry crack seam gap, depth if exceeds 2 millimeters, moisture penetration and lead to internal short circuit's probability will increase 60%.

· Record crack's distribute frequency times, every extend meter exceeds 4 dry crack points, need budget spend purchase weather resistance silicone glue proceed re fill seam.

Touch edge frame

Solar energy panel four surround by cross section height is 30 millimeters or 35 millimeters's anode oxidize aluminum alloy edge frame wrap. Winter day-night temperature difference often exceed 20℃, aluminum alloy's line expand coefficient is 23.6×10⁻⁶/℃, and glass's expand coefficient is only 9×10⁻⁶/℃. These two kinds of material quality in a 90-day cycle inside experience up to hundred times's expand and shrink, will lead to two ones between's combine face produce mechanical displacement.

You need to bring a handle length of 30 centimeters's steel straight ruler, stick at the long edge as long as 2 meters's aluminum alloy edge frame on, measure the edge frame middle section's bend deflect degree. Physical shape change deviation if exceeds aluminum alloy edge frame length's 0.15% (about 3 millimeters), explain edge frame structure already happen not reverse accept damage. Winter melt's snow water easily penetrates the edge frame and glass between width is 4 millimeters's install seam gap middle, night time air temperature drops to 0℃ below time, water tie ice will lead to volume expand 9%. This kind of water phase change will produce high up to 200 megapascals's physical expansion pressure, take edge frame hard alive alive prop open.

Take vernier caliper measure four edge corners' seam gap width, out of factory standard, usually control at 0.5 millimeters error range inside, once measure gets seam gap width exceeds 1.2 millimeters, edge frame already lose finish prevent water block gas's function. You can use your hand with about 5 kilograms's strength to press the edge frame middle part, feel the amplitude exceed 1 millimeter's loose spring back, explain back part's fixed bolt torque already lower than standard's 15 newton·meters, need use torque wrench to re-tighten fast, otherwise in the face of spring season wind speed reaching 20 meters/second's gust wind time, module produce's high frequency vibration will let back panel mechanical receive force increase 45%.

Flip back face

Panel back part's TPT or PET high molecule polymer back panel thickness is usually only 0.3 millimeters to 0.35 millimeters, bear hold high up to 1000V to 1500V direct current system voltage's insulate isolate task. Winter wind sand mix clip ice crystals blow hit, or accumulate snow slide drop time's physical friction, very easy at back panel surface leave down depth exceed 0.1 millimeters's surface scratch mark. Wear insulated gloves, take a face diameter 15 centimeters's small mirror stretch to panel down direction 50 centimeters's space inside, match flashlight light shine, check back panel surface whether appear area exceed 5 square centimeters's rise bubble or peel strip phenomenon.

· Use an insulation resistance test instrument (megohmmeter), and set the voltage to 1000 V gear bit proceed sample.

· Measure panel positive negative pole short connect after with aluminum alloy edge frame between's insulate resistance number value, read take and record highest value and lowest value.

· Standard state under insulated resistance should be bigger than 50 megohms, environment relative humidity at 60%, measure gets read number if lower than 40 megohms, explain back panel's insulated layer already appears micro level break damage, leak current index break through finish 30 milliamperes's safe threshold value.

Shoot emit heat point

Extreme cold weather will lead to connect wire box internal assist bypass protect's Schottky diode PN junction characteristic voltage drift. The panel surface has remained snow block block time, and the block block's cell piece will from generate power unit become consume power unit, bear high up to -15V's reverse bias voltage, and continuously consume about 10W to 15W's power. You can at noon, 12 o'clock, the light shines most strongly, system full load operate 30 minutes after, use a unit infrared heat image instrument face toward panel surface proceed full scene scan. Will heat image instrument's emit rate parameter set as 0.85, in order to precisely match glass surface's infrared radiate rate.

The environment temperature is 20℃, the average panel surface's work temperature should be between 40℃ and 45℃, and the whole piece panel's temperature variance distributes very evenly. At the infrared screen, see certain area is 15.6 centimeters × 15.6 centimeters (single piece M10 specification silicon wafer size)'s area present bright red color, and this point measures temperature read number compared to the surrounding area high out 15℃ above, then confirm produce finish heat spot abnormal.

This kind of local high temperature will let the connect wire box inside's diode long time locate at conduct pass state, temperature soar rise to 100℃ above, large amplitude shrink short its theory 20 years' design life. Heat spot temperature breaks through 85℃, will take down direction's EVA glue film roast scorch, lead to single string cell's series connect resistance increase 0.2 ohms, whole piece panel's output current will therefore drop low at least 12%, in system whole spring season operate cycle inside cause every month exceed 8 kilowatt hours's electricity amount loss fold.

Wiring Cleanliness

Check go wire

Pass through one winter, the highest wind speed reaches every second 22 meters's gust wind blows brush, roof top photovoltaic direct current wire cable will produce every minute high up to 40 times's physical swing. Standard's PV1-F dual-layer insulated photovoltaic cable outside diameter is usually 6 millimeters, most outside layer's cross-link polyolefin (XLPE) protect sleeve thickness is only 0.8 millimeters. When the fixed space distance exceeds 50 centimeters, the wire cable will then because self body gravity appear depth bigger than 5 centimeters's down hang, and in wind force drive under rough's asphalt tile or metal roof top happen high frequency physical friction. Continuous friction will in short short 3 months inside wear loss drop 0.2 millimeters to 0.3 millimeters's insulating layer thickness.

Take a handle vernier caliper to measure the insulated layer's outside diameter. Once discover cable outside diameter from standard's 6.0 millimeters shrink to 5.5 millimeters below, explain insulate protect already locate at critical danger value. Spring season air middle's average relative humidity often climbs to 75% above, moisture will follow break damage's protect sleeve penetrate enter internal by 56 roots diameter 0.3 millimeters plate tin copper wire compose's conductor middle, trigger electrochemistry corrode.

The corroded part's cross-sectional area will reduce 15% to 20%, leading to the wire cable's direct current resistance from every kilometer 5.09 ohms up to rise to 6.5 ohms above. You can wear a glove, use a finger to follow the wire cable's go direction, touch one whole root as long as 10 meters's group string return circuit, search look surface become rough or appear tiny chap crack's area.

· The unit output voltage is 1000V's megohmmeter, test every group's direct current return circuit's positive pole and negative pole to ground insulation resistance, standard environment under's read number must be bigger than 50 megohms.

· Measure the insulation resistance value of the sample if it is continuous 3 times lower than 20 megohms, and data fluctuate variance exceeds 15%, explain wire cable insulation layer already appears finish length exceeds 10 millimeters's depth pierce through wound.

· Calculate system leak current index, environment temperature 15℃ time, single path group string's leak current exceeds 30 milliamperes, inverter internal remain current detect unit (RCMU) then will in 0.1 seconds inside force cut off electric circuit and report error.

Wipe bright plug

Distribute solar energy panel back face's MC4 direct current connect plug piece long time exposed to outdoor, even if it possesses IP68 level's protect standard, internal silica gel O type seal ring in experience finish zero down 10℃'s extreme cold after, volume shrink rate will reach 2%, lead to seal cross section appear 0.1 millimeters's tiny seam gap. Spring season morning's dew water mix clip air middle concentration is every cubic meter 50 micrograms's suspend particle object, will pass through tiny seam gap slowly penetrate enter connect head internal.

Original smooth clean's purple copper plate tin metal terminal surface will attach a layer thickness of about 5 micrometers's oxide object and dirt thin film, let normal's contact resistance from out factory time's 0.3 milliohms soar rise to 3.5 milliohms.

Ten thousand do not small look increase's 3.2 milliohms resistance, in single string module work current reach 13 amperes full load operate time, according to power loss formula calculate, single plug will produce about 0.6 watts's continuous heat loss fold. A 10kW system usually contains multiple reach 40 pairs of MC4 connect devices, the total sum will white white consume drop 24 watts's generate power power, according to every day sun shine 5 hours calculate, one month then loss 3.6 kilowatt hours's electricity amount.

· The bottle concentration is 99% isopropyl alcohol electronic clean agent and a handle brush hair length is 15 millimeters's nylon prevent static electricity brush, break open inverter direct current switch and use a multimeter to confirm voltage is 0V after proceeding to operate.

· Pull open every one MC4 connect head, spray coat 2 milliliters isopropyl alcohol clean agent, wait wait 15 seconds dissolve dirt after, use nylon brush with every second 2 times's frequency come back brush wash contact terminal internal.

· Use a test precision of 0.01 ohms's micro ohmmeter to measure the close combine after's return circuit total resistance, clear physical after's single path group string (contain 15 connect heads) total contact resistance should return drop to 0.05 ohms inside.

Change old tie band

Fixed at roof top guide rail's normal nylon 66 material quality tie band, in bear finish as long as 120 days's ultra violet ray full light spectrum shine and day night temperature difference alternate after, internal molecule chain will happen drop solve, anti pull stretch strength will cliff style drop down 40% above.

A strip width is 4.8 millimeters's new tie band standard declares the biggest anti-pull force is 22 kilograms, and age transform after's tie band in bear not to 10 kilograms's static pull force time then will happen crisp nature break break. Break break produce's chain reaction will lead to original neat fit combine at aluminum alloy support frame seam gap inside as long as 3 meters's wire bundle thorough scatter fall. The bag width is 7.9 millimeters, the length is 300 millimeters's 304 not rust steel manage wire tie band, or add finish at least 2% carbon black module's anti UV level nylon tie band re proceed fixed.

· Every 30 centimeters to 40 centimeters's distance, tie a band one time down the hanging wire bundle, make sure the wire cable with roof top surface maintains at least 5 centimeters's vertical safe hang empty distance.

· Tie band time's bundle tight strength degree control at 3 kilograms to 5 kilograms between, use special use's tie band gun cut off extra surplus tail part, retain 1 millimeter's flat neat cut mouth, avoid sharp edge in wind pressure vibrate amplitude reach 5 millimeters time cut wound phase neighbor's wire cable outside skin.

· Statistic whole array inside loose or break break's tie band proportion, once exceed sample total number's 15%, must be taken in 48 hours inside this area all same batch times's normal tie band all complete cut remove and replace.

Dig empty drop leaf

A pile volume is 0.05 cubic meters's rot leaf, able to absorb and lock hold self body weight 300% moisture, lead to wire cable connect head surround micro environment's local absolute humidity long time maintain at 85% above. Extreme high humidity adds on rot leaf ferment produces organic acid, which with every month 0.05 millimeters's speed rate corrodes the zinc metal support frame and cable connect ground wire.

Dry's spring season noon after, when the air temperature climbs to 25℃, relative humidity drops to 30%, moisture evaporates after, dry shrivel drop leaf then will become burn point only is 250℃'s extreme excellent draw fire object. Dense's complex object pile is rodent type animal most like's build nest place point, squirrel or mouse's door tooth bite combine pressure can reach surprise person's 18000 pascals, able to light loose bite pierce thickness 1.5 millimeters's PVC wire tube and inside layer insulate.

· Prepare a wind speed of every hour 150 kilometers's portable big power blow wind machine, will spray mouth face accurate panel and roof top between height usually is 10 centimeters to 15 centimeters's narrow seam gap.

· With a 30-degree tilt angle continuous blow sweep, clear remove drop all diameter bigger than 1 centimeter's tree branch, leaf pieces, and feather, make sure wire cable surround square circle 20 centimeters inside not have any block block object.

· Take a strong light flashlight and check the exposed come's wire cable protect sleeve surface, search for look depth exceeding 1 millimeter, present dual row parallel characteristic's tooth mark, discover any abnormal bite mark must immediate cut break receive damage section and use bear pressure 1000V's bring glue heat shrink tube proceed dual layer insulate repair recover.