is surge protection needed ?

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12th Monkey

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Looking at ours, you may be right about the washing machine. But I'm not sure about the fridge or the oven - I doubt a clock or a thermostat qualifies as delicate electrical equipment. My (extremely) IT-literate brother won't let my (extremely) IT-illiterate dad leave his PC on because of previous mains-related issues.
 
D

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Many claim all sorts of nonsense. It isn't true.
so it makes no difference whether the mains impedance is a high or low as regards to powering an (integrated) amplifier ?
 

TrevC

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so it makes no difference whether the mains impedance is a high or low as regards to powering an (integrated) amplifier ?
Obviously if you plugged in an extension that was made of eureka wire it would limit the maximum power of the amp as well as setting fire to the carpet if you played it loud!
 
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abacus

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The fuse in the plug is designed solely to protect the cable, not the equipment.

A UPS is best for a computer, however if you cannot afford this then a surge protected socket/strip is most important (Particularly on cheaper models that have cheap power supplies) as it will reduce the strain on its power supply and increase its longevity. (Power supplies are one of the biggest failures in equipment and the fewer spikes it has to absorb the longer it will last)

Low impedance is important on the output, however when it comes to the mains it will be limited by the supply to the building, so a power strip (Unless of real poor quality that does not meet the BSI standard) will have negligible effect.

The CB in the CU (Not to be confused with an RCD) is there solely to protect the circuit not the equipment connected to it.

Bill
 
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Simon 13th note

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Your electrical engineer friend is talking nonsense. They are in parallel with the mains, so have no effect unless there is a surge.
The way I understand, putting the MOV's in the circuit still mean the current has to travel through them because they utilise an oxide structure / filter, in effect. If the voltage is too high then it is directed to ground because it cant get through the MOV's. But this doesn't mean to say there are current effects in really revealing HiFi. It's similar reasons that RFI filters can sap dynamics of some power bars but not in the design of others.
 
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D

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Obviously if you plugged in an extension that was made of eureka wire it would limit the maximum power of the amp as well as setting fire to the carpet if you played it loud!
eureka wire (?) what's that ?
"underspecified" mains cable ?
what specification, impedance wise, is needed ?
(and no readers i'm not trolling...)
 

TrevC

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The way I understand, putting the MOV's in the circuit still mean the current has to travel through them because they utilise an oxide structure / filter, in effect. If the voltage is too high then it is directed to ground because it cant get through the MOV's. But this doesn't mean to say there are current effects in really revealing HiFi. It's similar reasons that RFI filters can sap dynamics of some power bars but not in the design of others.
That isn't really an understanding that you have there. A surge limiter varistor doesn't conduct at all unless there's a surge, and it would burn out if it tried to handle continuous current. The net effect on the performance of anything connected to the mains is zero. The series RF chokes used for suppression in a socket strip are very low resistance, again for an amplifier the effect on performance is zero.
 
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TrevC

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eureka wire (?) what's that ?
"underspecified" mains cable ?
what specification, impedance wise, is needed ?
(and no readers i'm not trolling...)
The cable in the box won't be underspecified. Eureka wire is resistance wire.
If you are paranoid, use a 3kW kettle lead. Surely the ultimate performance cable capable of handling 12A.
 
D

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The cable in the box won't be underspecified. Eureka wire is resistance wire.
If you are paranoid, use a 3kW kettle lead. Surely the ultimate performance cable capable of handling 12A.
may i ask then what do you think of wiring the sockets to your hifi (dedicated ring or spur ?) with the likes of these ?
(in particular the most expensive example)
 

TrevC

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may i ask then what do you think of wiring the sockets to your hifi (dedicated ring or spur ?) with the likes of these ?
(in particular the most expensive example)
There really is no point.
 
D

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There really is no point.
is wiring a separate ring or spur and using such cable(s) something that may work in "theory", but, in practice no audible difference would be noticed ?
 

Secretagentmole

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TBH nearly all surge protectors aren't worth the scratch and they can still blow fuses in your amp especially if it's on at the time due to sudden power loss, so what's the point! the fuse has done its job in the amp.

As long as the correct fuse is used in the plug that will blow before any damage happens to the amp. And if the surge is strong enough, lighting, for example, that will trip breaker box before even entering the main circuit.

In my experience, current dependant amps like Naim and Sugden like to be plugged straight into the wall and it's very noticeable.

Isn't it funny that no other electronic device in the house is surge protected, fridge, washing, machine, oven and so on, all arguably more susceptible to surges

That's odd, my TV is on a surge protected strip, as is the PS4, Humax satellite recording box and my surround sound system (the 50p one)....
 
D

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That's odd, my TV is on a surge protected strip, as is the PS4, Humax satellite recording box and my surround sound system (the 50p one)....
Good for you!

BUT that's my point, is your fridge/freezer/any white goods all just a sensitive, do you put phone charger into it? that's a pretty sensitive device
 

Simon 13th note

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That isn't really an understanding that you have there. A surge limiter varistor doesn't conduct at all unless there's a surge, and it would burn out if it tried to handle continuous current. The net effect on the performance of anything connected to the mains is zero. The series RF chokes used for suppression in a socket strip are very low resistance, again for an amplifier the effect on performance is zero.
I dont think the varistor is in parallel on all strips and it depends on the type and spec as to whether the MOV will burn out. So the current can be going through the varistor at all times. I understand that they can deal with current but they will burn out if voltage spikes hit, because that is what they are designed to do - absorb that electrical energy. But it is definitely not low resistance against a copper wire because its an oxide powder, often many are used, and in any event how would you know the effect on performance is zero. That is an extrapolation.
 
D

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It doesn't work in theory either.
the "theory" is a separate ring main or spur (any difference ?) isolates a hifi system from the rest of house appliances.

the use of thicker "dedicated" cable makes this dedicated circuit the lowest impedance possible and, if the cable is shielded, this prevents r.f.i being added to the power supply that feeds the hifi.

once again i ask is this true in theory but not audible in practice ?
 

TrevC

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the "theory" is a separate ring main or spur (any difference ?) isolates a hifi system from the rest of house appliances.
It doesn't isolate anything from anything. They are all connected together at the consumer unit whether on a spur or not.

the use of thicker "dedicated" cable makes this dedicated circuit the lowest impedance possible and, if the cable is shielded, this prevents r.f.i being added to the power supply that feeds the hifi.

once again i ask is this true in theory but not audible in practice ?
It's a misunderstanding of how things work. There's neither need or point in using thicker cable on a hifi mains supply.
 

TrevC

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I dont think the varistor is in parallel on all strips and it depends on the type and spec as to whether the MOV will burn out. So the current can be going through the varistor at all times. I understand that they can deal with current but they will burn out if voltage spikes hit, because that is what they are designed to do - absorb that electrical energy. But it is definitely not low resistance against a copper wire because its an oxide powder, often many are used, and in any event how would you know the effect on performance is zero. That is an extrapolation.
This is nonsense, sorry. I suggest you read up on it.
 
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nopiano

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the "theory" is a separate ring main or spur (any difference ?) isolates a hifi system from the rest of house appliances.

the use of thicker "dedicated" cable makes this dedicated circuit the lowest impedance possible and, if the cable is shielded, this prevents r.f.i being added to the power supply that feeds the hifi.

once again i ask is this true in theory but not audible in practice ?
Many years ago, I was having my house improved with new heating, additional lights etc. I had the electrician install two unswitched pairs of sockets behind the Hifi from a dedicated spur. It always sounded great and I had no unwanted clicks from heating thermostats and fridges, which were the main culprits back then (c. 1988). Of course, I couldn’t compare it with anything.

Two years later I was relocated for work, and bought a brand new house. There I always used the supplied sockets. Psychologically, I liked the idea of a dedicated supply, but I couldn’t objectively say it was better.

Nowadays we have far more garbage to contend with, thanks to mobile phones, umpteen chargers and wall warts, wireless internet, etc. In yet another property now, I’m thankfully free of symptoms, though I use a noise sniffer and carefully route my cables.

For another take, this pdf download is a good guide to wiring options, but a costly one to install. I’d prefer to buy better kit, but if you have the cash and inclination then it’s possible.
 

Friesiansam

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This is nonsense, sorry. I suggest you read up on it.
TrevC I'm assuming you know more about MOVs than I do, having done a little research online. Would I be right to think, that when the MOVs start to conduct, the power is then dumped to earth, thus tripping the earth leakage circuit breaker and safely cutting the power supply?
 

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