All rights reserved.

Energy audit on site

V02

September 2011-2013

Andreas Iliou

TCS EEngineer

claim 1 – Power produced ,less than expected

• Client complains about less efficient system

(e.g inverter A towards B )• Check strings alone and compare with each other (with Ampmeter)

• Check Voltage and current (mismatch-shortcut-bypassdiode still working ?)

• Voltage ok ?! Uo

If Voltage is nearly the same –carry on with current

• String with less voltage or current – probably shaded ?

• Visual inspection of string wether shaded or not – probably dirty (birddrops)

claim 1 – Power produced ,less than expected

• Check layout of inverters

• change the two inverters and check again current and voltage

• If value still the same …check inverter temperature

• if value changed , check air vent of 2nd inverter – clean if necessary• Rearrange position of inverter if it gets pre heated air • Change the position of the inverter and….. – check again

• If still less efficient check cable size –keep in mind max drop < 1 %• If everything ok , check loop of system and change supply line• If not satisfied with measurement

claim 1 – Power produced ,less than expected

Measurements :

1) Visual Inspection cells or cracks – if ok

2) Check voltage of different strings e.g 80V DC less ??

3) Measure current: module is producing 1,5A other strings produce 2,3-2,4A instead

….check with label – backside

If the system is not shaded , carry on with thermal image

claim 1 – Power produced ,less than expected

Hotspot issue:

4) Thermal image from the front view

5) If it s problematic- clean surface and make another pic from the back

claim 1 – Power produced ,less than expected

Solution :

6) Visual inspection if the module shows same hotspot from back and front view:

Þ No visual crack or hotspot to be seen

Outcome of inspection e.g:

- J-boxes show hotspots as well- More than one cell shows hotspot issues- E.g Voltage measured is only 2/3 of Uo (28V actual reading <-> 44V DC labelled)- Diode is defect j-box must be changed

claim 2 – Power produced ,less than previous years

Claim 2:

check if the system is shaded or dirty – if not ?!

are the cables damaged or defect- if not?!

check with Tool like ( Tri Ka )

and compare with existing datas from prev. years

check corrosion or weak connections

are their any shortcuts ( modules or bypassdiodes )- if not ?!

cell damage in the module- cracks

shortcut inside j-box ( water ) – if not ?!

problem of degradation ?!

how old is the system- output power still as expected ?!

claim 3 –No power produced during daytime

Claim 3:

meter not turning at all

is it still cloudy or dark outside ?!

check dc switch – or + broken – if not ?!

check AC breaker or earth leakage tester – if not ?!

check over protection unit -> shortcut – if not ?!

measure strings seperately

problem with frequency –if not ?!

check voltage of each phase –if not ?!

No DC supply:

Probaly to dark or less starting voltage

Inverter or tracker damaged

Fault on iso, check each string individually