Over 50 residential houses got 480 volts

[bach]

Just finished piping/vacuum, all wiring job for a Fujitsu 2.5HP conventional (AST24UBBJ model). When I turned on the circuit bracker and the Isolated swith, there was a big noise and have a flased from out door unit, the circuit braker turned off immediately. Checked all wiring cable, OK.
Measured tested, I found the voltage is 480 volts (in Australia only 240volts). So opened the outdoor unit cover, I found the 5A fuse was blowed up. Oh my god! I knew It have another fuse inside the indoor circuit (may be about 3.15 A) I'm not sure it will be blowed up or not. I'm worry there will be damaged more than that. The next day, I got the news from all neighbors of this house, they claim there were too many electrical items blowed up(about over 50 houses). With a few witness, I'm not sure the amount of 50 houses is correct or not. But to me, first of all I must to ask someone to give to me the circuit diagram, for a preparing the process of test the indoor circuit. Can anyone help?Thanks

[nike123]

Turn on your PM or send me PM with your e-mail!

[nike123]

If you are lucky, you could only change fuse F1.
If you are little less lucky, you should change also VA1 and/or VA2 also VA3(varistor 470V 12A).
And, if you are little unlucky you gonna need to change/rewind transformer .

[ozairman]

Don't forget the thermal fuse under the terminal block on the indoor it tends to go open circuit and requires a new terminal block as it is a one time blow item. The Varistors if you don't know are the green little disc things that are normally located very close to the fuse on the controller pcb. In your case they are probably blackened and split which means they need replacing or if you are not up to it and the power company or whoever admits liability then just replace the pcb and keep that one as a spare that you can practice repairing later.

And finally thank god that it was not an inverter machine with DC fan motors and such, things get expensive to fix then

[drew71]

Hi bach
Just a thought, but if the situation is as you say, the supply authority would be liable for any parts,labour or service call. I hope you are not trying to fix this out of your own pocket.
Was 480 volts measured phase to earth or neutral ? if so & it was sustained long enough for you to get the meter and take a measurement, its a serious issue and the Authority will be bending over backwards to resolve and compensate.

Cheers
Drew

[thermo prince]

With all we've been reading here on "moving to Aus" threads about the high standards, paperwork, certification etc for intending migrants .... how the heck did 480V supply to residential housing sneak by the State & Local Authorities.
I presume you are talking of the 1ph supply since you said Aus is 240V, not 3ph industrial.
If I am not mistaken your domestic 1 ph should be 240/1/50 while 3 ph is 380/3/50.

With all respect to Aus but that sounds like something could happen in Banana Republic only!
I'd be more concerned with serious injury or worse, than a few blown fuses or damaged machine. Machine can replace, not a life.
What are those residents doing about it?

best regards
T-P

[nike123]

With all we've been reading here on "moving to Aus" threads about the high standards, paperwork, certification etc for intending migrants .... how the heck did 480V supply to residential housing sneak by the State & Local Authorities.
I presume you are talking of the 1ph supply since you said Aus is 240V, not 3ph industrial.
If I am not mistaken your domestic 1 ph should be 240/1/50 while 3 ph is 380/3/50.

With all respect to Aus but that sounds like something could happen in Banana Republic only!
I'd be more concerned with serious injury or worse, than a few blown fuses or damaged machine. Machine can replace, not a life.
What are those residents doing about it?

best regards
T-P

That high voltage could be because of partial short circuit in high voltage side of power transformer (distributor power transformer) . If that is the case, you have changed transformation ratio and that is why you could have 480V on 240V line.
Don't ask me how I know that!

[monkey spanners]

Some uk supplies have only two phases instead of the usual three and are 480V across the phases and 240V to neutral. The phases are 180 degrees out as oposed to 120 degrees with three phase. Its known as split phase. Any compressors running on it have the usual start, run, common terminal (and start electrics) but with an extra run terminal for the other live.

[thermo prince]

That high voltage could be because of partial short circuit in high voltage side of power transformer (distributor power transformer) . If that is the case, you have changed transformation ratio and that is why you could have 480V on 240V line.
Don't ask me how I know that!

Nike123, my friend no doubt something like you say happened at the 'upstream' side at the distribution but how many days does it take the Utility company to send some 'sparkys' out to remedy hazardous situation like this?

regards
T-P

[paul_h]

With all we've been reading here on "moving to Aus" threads about the high standards, paperwork, certification etc for intending migrants .... how the heck did 480V supply to residential housing sneak by the State & Local Authorities.
I presume you are talking of the 1ph supply since you said Aus is 240V, not 3ph industrial.
If I am not mistaken your domestic 1 ph should be 240/1/50 while 3 ph is 380/3/50.

With all respect to Aus but that sounds like something could happen in Banana Republic only!
I'd be more concerned with serious injury or worse, than a few blown fuses or damaged machine. Machine can replace, not a life.
What are those residents doing about it?

best regards
T-P

Power surges are extremely common here. I've mentioned a few times how the electrical standards are poor, at the same time griping about how they lord it over other trades like refrigeration
But then again, repairing splits after the regular supply surges is going to hopefully be a money maker for me when I'm self employed as I am learning the ways to repair the PCBs rather than replace the whole lot.
The power companies aren't very good here, caused quite a few deaths with there transformers starting fires.

[bach]

Hi Nike123,
Yes, please rescue me with your circuit diagram Fujitsu AST24UBBJ model.My email: Admin removed
Best Regards.

[paul_h]

Normally with power surges it's just the fuse blown because a varistor has shorted to protect the PCB.
Though the last one I went to that had a surge blew the main capacitor, so it probably blew the diode bridge as well the fuse and varistor.
I'm learning a fair bit about electronics from the guys at badcaps.net, a PC based forum mainly repairing PC power supplies.
I've sent an email BTW.

[bach]

i would like to say thanks to Paul for your help. I will inspect the outdoor unit first and the indoor after that. With the out and indoor circuit diagrams, I will report to the forum about the result of damage in my case. Thanks everyone for helping me with all suggestions, ideals, supporter for mails the circuit diagrams.
Special thanks to Paul and Nike123

[The MG Pony]

usualy what I do when repairing veristers is I'll size them up to handle heavier surges, they last longer and give better protection, so if Aus is pron to lots I'd think about it less it would violate any thing there!

All so see how they wire it, some cheap methodes are doing it just from L1 to L2, but if it has a ground circuit a better way is:
L1 to G
L2 to G
L1 to L2

Provides max protection and will snuff out transient surges from either line.

[Peter_1]

Bach, isn't the electrical supplier not responsible for this damage?

[paul_h]

Yes, all he'd have to do to say "not his problem" tell the owner to contact the electricity supplier and the service agent to sort it out.
The same as the LG which was short of refrigerant at install in his other thread.
If he wants to learn, I'll help and reply to his posts, but the installer here in australia doesn't have to deal with any faulty units, let alone spend money out of their pockets dealing with repairs. If you are not a factory authorised service agent, neither the manufacturer or the power company will pay you for your troubles.

Even when I, as working for a factory service agent, don't pursue the power company for bills.
We charge the customer, and they claim off the power company or through insurance

[Peter_1]

Paul-, I think you misunderstood me...the AC-tech of course has not leave the client to leave with his problem.
It's the owner who must go to the electricity supplier and file a claim.
It's an European law and I think it's a universal law that everybody who broke something of someone else must repair it so that it becomes in the same physical situation before it was broken.
That's why you pay insurance, in case something goes wrong.
But you must prove you have damage, that this damage was provoked in a not normal way (you couldn't have done something to avoid the damage) and you must have a prove of who who broke it.

The fact that these are perhaps huge companies has nothing to do with it.
If 50 houses have damage, then there's no doubt left what went wrong. Then they all can pay together for a lawyer and make a case of it.
I'm almost sure they will win it.

The LG thread is something completely different; if the unit was undercharged (was it??), then how can you prove that it was undercharged? Perhaps you had a bad flare and tries this way LG pays for it. You can't prove that LG did something wrong. And you also have to prove your damage which are only loss of gas and labor hours.

Of course you can give advice but the end-user finally must try that the electricity company will pay the amount he paid to the tech.

The phrase 'dealing with a faulty unit' should be written better of a unit they have broken which is something completely different. And then they have to deal with it.
I'm sure in a civilized country like Australia that the law is there almost the same as we have here.

So, my post ' isn't the electrical supplier not responsible for this damage', what's wrong with it?

[paul_h]

Sorry, that's the way it works here. Installers here are sometimes not even licenced to buy refrigerant.
They do their job fitting the unit, and in theory they do their job right. If the machine doesn't work, they walk away and tell the customer to contact authorised service agents. People who are not an authorised service agent will not get paid by the manufacturer for any repairs or extra work they do rectifying system faults.
In a perfect world, it's the installer who contacts the service agents, and they get billed for any installer mistake.
The reality of the situation is the installers leave, never to return and the customer calls us. The customer gets no repairs done, (taking the option to hopefully get the installers back to redo the job), or pays us to re-do the install properly edit: If an installation mistake, not a unit fault.

So many systems are installed before power is even connected, and have no commisioning done. This time of year I'm attending units that the installers haven't even opened the service valves or done the flares well.

I work for a manufacturer authorised agent, when dealing with damage to equipment from power surges etc, we bill the customer, and let them sort out reimbursment through the power company or insurance.
This is how it's done here, we'd rather do no repair than chase up power/insurance companies for payment a few months down the track.

edit: as a service agent, It's me that has to prove the installer is too blame. If I pressure test and find a leak on the installers lines, I give the customer the "call them back to repair, or pay me to fix".
If a leak not found, the benefit of the doubt is given to the installer, I normally reflare and vac and charge.
I've tried fighting the fact that even no leak found, the flares were very bad. But the manufacturer rather not fight the customer, retailer, installer that can't buy refrigerant anyway etc.

[frank]

Sorry, that's the way it works here. Installers here are sometimes not even licenced to buy refrigerant.
They do their job fitting the unit, and in theory they do their job right. If the machine doesn't work, they walk away and tell the customer to contact authorised service agents. People who are not an authorised service agent will not get paid by the manufacturer for any repairs or extra work they do rectifying system faults.
In a perfect world, it's the installer who contacts the service agents, and they get billed for any installer mistake.
The reality of the situation is the installers leave, never to return and the customer calls us. The customer gets no repairs done, (taking the option to hopefully get the installers back to redo the job), or pays us to re-do the install properly.
So many systems are installed before power is even connected, and have no commisioning done. This time of year I'm attending units that the installers haven't even opened the service valves or done the flares well.

I work for a manufacturer authorised agent, when dealing with damage to equipment from power surges etc, we bill the customer, and let them sort out reimbursment through the power company or insurance.
This is how it's done here, we'd rather do no repair than chase up power/insurance companies for payment a few months down the track.

edit: as as service agent, It's me that has to prove the installer is too blame. If I pressure test and find a leak, I give the customer the "call them back to repair, or pay me to fix".
If a leak not found, the benefit of the doubt is given to the installer, I normally reflare and vac and charge.
I've tried fighting the fact that even no leak found, the flares were very bad. But the manufacturer rather not fight the customer, retailer, installer that can't buy refrigerant anyway etc.

This is rather eye opening especially when we read in other threads that the qualifications we have in the UK are not recognised in Aus

The Aus system sure seems weird.

[paul_h]

It's weird because there's not enough fridgies here, or fridgies interested in install work anyway. So it ended up most installs being done by plumbers, sparkies or labourers.
The tight regulations we have here seem to only apply to fridgies who purchase refrigerant. As systems are precharged, we get the installers operating without strict control.
There's a lot of refrigerantion companies who do install and know what they are doing, don't get me wrong.
But the installers organized by the electrical retailers selling splits are low quality. These are the guys that I have to chase around every summer.
That's why I handed in my notice on friday. I'm sick of repairing faults done through incompetance, by doing this job I'm just supporting the system and the bad installers.
I rather just repair well installed and designed systems that broke down through normal wear and tear, not going to dead on arrival systems and explaining the system we have to customers and the fact the installers suck here and be stuck in the middle of this situation.

[frank]

A man of principles - I like that

Good luck with the new job.

[Peter_1]

when dealing with damage to equipment from power surges etc, we bill the customer, and let them sort out reimbursment through the power company or insurance.

That's what I was trying excatly to explain in my best English.

[Josip]

Hi, all

This is rather eye opening especially when we read in other threads that the qualifications we have in the UK are not recognised in Aus

The Aus system sure seems weird.

I must be sarcastic a little here...if you are good qualified then you are not able to make such a mess.....

......it ended up most installs being done by plumbers, sparkies or labourers.....

....then in another hand you do not have unemployed people...even contrary.....need to call a lot of them to repair that mess.....

Best regards, Josip

[paul_h]

Went to an a/c that had a power surge today (I told you they were regular )

The indoor PCBs survived intact.
The outdoor PCB (it was a cassette unit), had a blown varistor.
Funny thing was the fuse didn't blow even though it melted the fuse holder a bit, the track burnt out instead!
Everything was OK though, a varistor replacement and solder/track repair and off it went, worked perfectly.
I was a bit worried when I looked at first, heaps of scorching aroung the fuse, I thought the PCB was a goner when I realised no fuses were blown.

[anesti]

Hi!
Varistor must to be 270 v,12A if the sistem is 220v.It is a kamikase in the electrik line.If tension is up to 270v put the line in short-circuit and so the fuse was blowed up.I am not insure for a varistor with 470v,I belive the kamikas is sliping for a tesion highter to 270v.

[paul_h]

I'm not exactly sure what you are saying, sorry.
But panasonic I know use 470V varistors (they still blow on a surge though), and I think fujitsu use 380V?

[nike123]

I think fujitsu use 380V?

Nope. They are use same 470V 12 Amp varistor.
When it blows it blows because he is not up with current and not because his nominal voltage. Current depends on ammount of voltage surge and if it is big, also current is big and varistor blows.