Thread: Solar controllers

Originally Posted by Robmacca

Not sure where u live but here in QLD I can say with 100% that the Power Service cable coming into your house from the street IS fused. It is HIGHLY dangerous not to have it Fused. It's usually located on the Pole or the Underground Pillar box on the footpath for those in underground powered estates.

Here in WA only some of the overhead connections are fused, most rural at the transformer and some domestic
None of the underground consumer mains are fused, not individually anyway, I would assume western power have (high current) fuses at the transformer

Gav

Originally Posted by trout1105

Yes I do have a pole fuse But that won't stop me getting electricuted because it takes quite a massive short to blow that partiular fuse.

Correct as its rated to protect the service cable coming in... RCD's are really the only thing that will hopefully protect u from getting electrocuted... generally

Originally Posted by Robmacca

Correct as its rated to protect the service cable coming in... RCD's are really the only thing that will hopefully protect u from getting electrocuted... generally

Which brings us back to my point about there being no fuses that will protect the house nor occupiers between the power pole and the house switchboard
The pole fuse is there to protect the power grid and not the house.

Originally Posted by Gav 110

Here in WA only some of the overhead connections are fused, most rural at the transformer and some domestic
None of the underground consumer mains are fused, not individually anyway, I would assume western power have (high current) fuses at the transformer

Gav

WOW, that is surprising and very dangerous too (ie for a fault between the pole and your switchboard the Fault Current could burn your house down if your house mains were not fused)...
I work for Utility business here in QLD and ALL premises (Overhead/Underground) have to be individually Fused as u do not want a fault in someone's premise to effect the whole area by isolating back at the local distribution transformer. This would be a nightmare to find/locate as well.


I would be very surprised it that is the case in WA. In the Outback it maybe different but still hard to believe. On SWER lines there is usually individual Transformers for each remote customer and I still think that they too would have a LV fuse at the Transformer.


When it comes to a full large solar system u start talking about electronics, etc which is above my head...

Originally Posted by trout1105

Which brings us back to my point about there being no fuses that will protect the house nor occupiers between the power pole and the house switchboard
The pole fuse is there to protect the power grid and not the house.

No not exactly... It's there to protect the CABLE from the pole down into your switchboard only and should be rated according to the size cables u have...

Originally Posted by Robmacca

WOW, that is surprising and very dangerous too (ie for a fault between the pole and your switchboard the Fault Current could burn your house down if your house mains were not fused)...
I work for Utility business here in QLD and ALL premises (Overhead/Underground) have to be individually Fused as u do not want a fault in someone's premise to effect the whole area by isolating back at the local distribution transformer. This would be a nightmare to find/locate as well.


I would be very surprised it that is the case in WA. In the Outback it maybe different but still hard to believe. On SWER lines there is usually individual Transformers for each remote customer and I still think that they too would have a LV fuse at the Transformer.


When it comes to a full large solar system u start talking about electronics, etc which is above my head...

Definitely no protection or isolator between the underground power dome and the house

There is a meter fuse to protect the meter and as we are no longer allowed to work on or near live electrical equipment, we are now allowed to use that fuse to isolate before working on a switchboard

Back on topic
A fuse at the panels sounds like a feasible idea but it adds another point in which can cause a problem, heat, moisture, dust etc all have the possibility to cause the fuse to arc/blow
As Trout has said if you protect the cable well enough you won’t have a problem
If by chance he cable does short out, the voltage isn’t high enough for the cable to continue burning and cause more damage

Like rooftop solar isolators, I believe a fuse would cause more problems


Gav

Originally Posted by Gav 110

Definitely no protection or isolator between the underground power dome and the house

There is a meter fuse to protect the meter and as we are no longer allowed to work on or near live electrical equipment, we are now allowed to use that fuse to isolate before working on a switchboard

Back on topic
A fuse at the panels sounds like a feasible idea but it adds another point in which can cause a problem, heat, moisture, dust etc all have the possibility to cause the fuse to arc/blow
As Trout has said if you protect the cable well enough you won’t have a problem
If by chance he cable does short out, the voltage isn’t high enough for the cable to continue burning and cause more damage

Like rooftop solar isolators, I believe a fuse would cause more problems


Gav

Ever tried to make an arc with a 40V panel? You'll be surprised

Originally Posted by Vern

Ever tried to make an arc with a 40V panel? You'll be surprised

I have on a 270watt 38voc 9isc
It will only burn for a few seconds before the burnt insulation creates enough of a barrier that the arc will stop
If you “draw” an arc by holding the cables apart you can keep it going for a while

You need the panel to be putting out full current to make it happen

You ever seen a parallel string at around 700volts arc?

That’ll scare the **** out of ya (and anyone else in sight)