1. Energy audit on site
V02
September 2011-2013
Andreas Iliou
TCS EEngineer
All rights reserved.

2. claim 1 – Power produced ,less than
expected
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•
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)

3. 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
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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

4. 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

5. 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

6. claim 1 – Power produced ,less than
expected
Solution :
6) Visual inspection if the module shows same hotspot from back and front view:
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

7. 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 ?!

8. 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