Solar Panel Maintenance
Ever bought a new car and wondered why they give you the first service free? Because it enables them to ‘finetune’ any possible issues with the vehicle after you have driven the first 3000kms. Otherwise they might expose themselves legally to defects or accidents that could occur.
So why is it that a lot of solar installers think that they can walk away from the job and ignore any maintenance issues? Here is an outline on what our Renewable Energy Standards say.
AS/NZ 5033 CLAUSES AND MAINTENANCE
• Documentation – a maintenance schedule and recommended maintenance required must be left with the customer – 5.7
• Appendix C outlines the maintenance that may be required:
a) Bolts on tilt frames, mid and end clamps are in place and tight
b) Vermin – has any cabling been disturbed or damaged?
c) Do the isolators still work, IP rating not affected?
d) Conduit and fittings – are these still in good order?
e) Panels – are these clean, undamaged and working? (hail can be an issue)
f) Verify the Voc and Isc and check it is what is expected
g) Labels – are they still in place and legible?
h) Have there been modifications to the building which would now inhibit the panels?
i) Have trees grown which now shade the system?
j) Are there fans or filters that need checking or cleaning?
k) String fuses – check terminals and verify they haven’t blown. Are they the right type and curve?
l) MC4 connections – is there evidence of arcing?
m) ‘hot spots’? use an infra-red camera
• Table C1 outlines the periods for this maintenance
AS/NZS 4777.1 CLAUSES AND MAINTENANCE
The ACT Government introduced a requirement for testing of the AS/NZS 4777.2 ‘Anti-Islanding’ function of the inverter. An accredited installer has to check this every five years and sign off on its functionality. Ausnet in Victoria also recommend this be done every year. If the DNSPs are concerned about this perhaps you should be as well.
• Appendix D suggests a Maintenance Schedule
a) Verify 60-second startup and/or ramp up
b) Verify that the DNSP network parameters (if set) are still in place – see 3.4.4
c) Central protection, phase balancing and export limiting – is it working as required?
d) Verify two-second shutdown
e) Verify connections are sound and not damaged
f) Earth fault alarm, emails and messages – are these still current?
g) Check earthing including earth stakes – the inverter can affect this due to a DC current being injected onto the AC cabling
h) LGCs – verify that the readings for the CER have been made and submitted
i) Check for polarised isolators and replace
j) Isolator terminals are the correct torque – use a torque screwdriver
k) If using an RCD on the output of the inverter test it (the RCD has to be a particular type, not an AC type)
AS/NZS 4509 AND ASNZ 4086 CLAUSES AND MAINTENANCE
Batteries and generators and other turbines: now we really have our work cut out for ourselves. Whether on or off-grid, these add another dimension to the maintenance requirements. While too extensive to list, here is where you would find some of the information.
• Appendix A – 4509 Part 1
• Generators – follow the recommended procedures from the manufacturer
• Section 3 – 4082 Part 2
TIPS FOR INSTALLERS
• Install off-site monitoring if possible and look at your customer’s systems
• Develop a procedure for maintenance and allow for it in your quotes
• Consider maintenance as just part of your job and not some other person’s responsibility
• With off-grid jobs this is particularly important – allow a six-month maintenance visit
• Your customers will appreciate your efforts and you are less likely to have problems later on.