New Solax Panels and Inverter breaker tripping all time

[whinmoor]

A few basic questions:

1. How many panels? What brand and wattage?

2. What model of Solax? - Check nameplate on side of inverter. Is it the "SL-TL3600" or "SL-TL3600T" or something different?

3. Has the installer checked the inverter is set up for UK usage? If not, suggest it.

4. Has the installer tried a different mini consumer unit? Maybe a different brand might work. Suggest it.

5. If it's a TL3600 or TL3600T, has the installer used 4mm AC cable and a 25A MCB as recommended in the installation instructions? If not, suggest it.



6. Has the installer offered to try a different brand of inverter? If not, suggest it.

 

[Worcester]

@whinmoor

25A, that's a very unusual recommendation, any idea why that high?
Would tend to indicate that it's not G83 compliant.

 

[davesparks]

@whinmoor

25A, that's a very unusual recommendation, any idea why that high?
Would tend to indicate that it's not G83 compliant.

Looking at the snapshot of the instructions which has been posted if say it wasn't written by someone with a good knowledge of UK wiring practices or regulations!

 

[whinmoor]

@whinmoor

25A, that's a very unusual recommendation, any idea why that high?
Would tend to indicate that it's not G83 compliant.

I don't know. Suggests to me they are worried about getting spikes well over 3.68kW and can't control or guarantee the limiting function in certain conditions. Could be that they are concerned when installers fit 5kW (or even more) of panels and use the inverter to cap at G83 levels.

Could be that it's a typo but I doubt it. I prefer the explanation above.

Probably a question for their technical team rather than a humble installer.

 

[AWAKEFIELD720]

A few basic questions:

1. How many panels? What brand and wattage?

2. What model of Solax? - Check nameplate on side of inverter. Is it the "SL-TL3600" or "SL-TL3600T" or something different?

3. Has the installer checked the inverter is set up for UK usage? If not, suggest it.

4. Has the installer tried a different mini consumer unit? Maybe a different brand might work. Suggest it.

5. If it's a TL3600 or TL3600T, has the installer used 4mm AC cable and a 25A MCB as recommended in the installation instructions? If not, suggest it.

View attachment 29639

6. Has the installer offered to try a different brand of inverter? If not, suggest it.

Hi,

Number of panels - 16 - 2 x string of 8 = 4 kw system - Solax panels 250w

consumer unit ?? sorry I don't know what that is

they are using a 20A MCB that keeps tripping - Inverter model no il check at dinner time

il mention the uk usage thing thanks

 

[AWAKEFIELD720]

How do I add the graph images ? cant see how to upload image like on original post ? only enter url which I don't want to do ? want to upload thumbnail ....

 

[AWAKEFIELD720]

Hi,

Number of panels - 16 - 2 x string of 8 = 4 kw system - Solax panels 250w

consumer unit ?? sorry I don't know what that is

they are using a 20A MCB that keeps tripping - Inverter model no il check at dinner time

il mention the uk usage thing thanks

Its a TL-3600 ... should be a 25A MCB then not 16 or 20 like they have used ... can you send me the full document this is extracted from ? thanks

 

[TedM]

http://www.solaxuk.co.uk/download/SL-TL_Install_Manual.pdf

 

[AWAKEFIELD720]

Thanks, just got it from Google. really strange that the maximum current output in the graphs I have are all below 16A yet its tripping on a 20A breaker ... Im very confused

 

[jason121]

What about C rated MCB ??

 

[davesparks]

Thanks, just got it from Google. really strange that the maximum current output in the graphs I have are all below 16A yet its tripping on a 20A breaker ... Im very confused

What you won't be able to see on the graphs as they are likely to be based on average readings for the sampling period is that there may be current peaks in the output.
We either increase the size of an MCB or use different types of MCB to avoid it tripping from these current peaks.

 

[Gavin A]

This makes no sense, an mcb is rated to carry its full load current indefinately. The tripping curve will always be above it's rated current for its rated operating environment (ambient temp, altitude, humidity).
Do you have a graph of the output current of one of these inverters outputting at maximum?

experience indicates this is not always true in practice.

None of the curves I've seen run past 10000 seconds, or under 3 hours, some of our systems can be running at full capacity for 6-8 hours at a time.

And you're ignoring the impact of ambient temperature, which when these units are in an enclosed board, and running at full load on hot sunny days in summer for so long does result in the air temperature inside the board rising significantly, and I've felt an MCB after it's tripped and it must have been at 50-60 degrees C.

At 40 degrees C ambient temperature there's between a 5-10% derating, rising to 12-20% at 55 degrees.

http://www.farnell.com/datasheets/1672135.pdf

 

[Gavin A]

It cannot be classed as a load, it is a source of energy!
A load is a component or part of a electrical circuit which consumes electrical power, a source of energy is that part of a circuit which produces electrical power.
(Technically it is the conversion of energy from one form to another rather than consuming/producing power, but that is irrelevant to the point)

I'm sure he does know more about solar than me, but the point still remains that a specialist company has installed a system which does not function as intended and have repeatedly failed to rectify the situation.

ffs it's the same as a load for the purposes of what it's doing to an MCB, albeit that the power is running in the opposite direction.

Unless your contention is that the direction of flow makes a difference, then you're just willy waving about an irrelevant point that should have been entirely obvious to anyone with half a brain. Was that your contention or were you just willy waving?

 

[davesparks]

ffs it's the same as a load for the purposes of what it's doing to an MCB, albeit that the power is running in the opposite direction.

Unless your contention is that the direction of flow makes a difference, then you're just willy waving about an irrelevant point that should have been entirely obvious to anyone with half a brain. Was that your contention or were you just willy waving?

I know the direction of current flow is inconsequential to an mcb.
But a source of energy and a load are not the same thing, it is not willy waving as you put it but a fundamental point of the science of electricity. If a person claiming to be an electrician cannot get such a fundamental point right then I would seriously doubt their credibility.
When a source of energy begins to act as a load then there is serious problem likely to have some disasterous results.

 

[davesparks]

experience indicates this is not always true in practice.

None of the curves I've seen run past 10000 seconds, or under 3 hours, some of our systems can be running at full capacity for 6-8 hours at a time.

And you're ignoring the impact of ambient temperature, which when these units are in an enclosed board, and running at full load on hot sunny days in summer for so long does result in the air temperature inside the board rising significantly, and I've felt an MCB after it's tripped and it must have been at 50-60 degrees C.

At 40 degrees C ambient temperature there's between a 5-10% derating, rising to 12-20% at 55 degrees.

http://www.farnell.com/datasheets/1672135.pdf

Then the mcb has been incorrectly installed. Alternating of high and low load MCBs and leaving gaps between them to allow the dissipation of heat should be considered in the design.