SURGE PROTECTION EXTENSION LEAD QUESTION

Griff7520

Griff7520

Griff7520

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Hi all
I bought an extension lead/ surge protector from the rain forest which should have been 13amp/3250watt but what I recieved is a 10amp/2500watt. I have 2 computers and 2 monitors connected to it. My question is is this cable safe to use.

It actually lets you connect 12 plugs but I am only using 4 for pc and 1 for a desk lamp, any opinions, thanks

its this one
 
4 For PC? I assume, PC, 2x Monitors and a ??? plus desk lamp?

Look at the fuses in the devices is the best way to calculate, you'd probably find your PC will be fitted with a 13A but it wont draw this, you'd need to calculate the peak demand from each of your components...
 
Fuses are there to limit the current in a cable to prevent overheating under fault conditions. I can see from the photo that the cables are certainly not 13A capable so the ones for the monitors and the lamp really ought to have 3A fuses in the plugs. The rating for each PC is governed by its PSU so either 3A (for a standard PC) or 5A for most gaming PCs (only extreme PCs will need 13A fuses).

The tower itself will have a 13A fuse in the plug. Then there will be additional protection within of the electronic or electromagnetic type (i.e. circuit breakers). The point of "surge protection" is that these act faster than fuses.

To the OP's question "is it safe to use?" the answer is absolutely. The more appropriate question should be "is it suitable for my use?". The answer can only be determined by checking the actual power requirements of each device, which should be easy, but ideally by also considering the surge rating which is usually difficult to find. It would be reasonable to ignore monitor and lamp surge and apply a "rule of thumb" factor of 1.5 for the PCs. So for example:
Lamp 60W
Monitor 1 50W
Monitor 2 40W
PC1 700W -> 1050W with surge assumption
PC2 400W -> 600W with surge assumption
Total 1,800W including surge
This would be well under the 2,500W rating of the tower so it shouldn't trip under normal use and has a good chance of not blowing the 13A plug fuse under a fault surge (which avoids inconvenience).
 
therealdippy said:
Fuses are there to limit the current in a cable to prevent overheating under fault conditions. I can see from the photo that the cables are certainly not 13A capable so the ones for the monitors and the lamp really ought to have 3A fuses in the plugs. The rating for each PC is governed by its PSU so either 3A (for a standard PC) or 5A for most gaming PCs (only extreme PCs will need 13A fuses).

The tower itself will have a 13A fuse in the plug. Then there will be additional protection within of the electronic or electromagnetic type (i.e. circuit breakers). The point of "surge protection" is that these act faster than fuses.

To the OP's question "is it safe to use?" the answer is absolutely. The more appropriate question should be "is it suitable for my use?". The answer can only be determined by checking the actual power requirements of each device, which should be easy, but ideally by also considering the surge rating which is usually difficult to find. It would be reasonable to ignore monitor and lamp surge and apply a "rule of thumb" factor of 1.5 for the PCs. So for example:
Lamp 60W
Monitor 1 50W
Monitor 2 40W
PC1 700W -> 1050W with surge assumption
PC2 400W -> 600W with surge assumption
Total 1,800W including surge
This would be well under the 2,500W rating of the tower so it shouldn't trip under normal use and has a good chance of not blowing the 13A plug fuse under a fault surge (which avoids inconvenience).
Click to expand...
main pc which has a 750watt psu and is a 5 amp plug
second pc has a 550watt psu and is a 10amp plug
Both monitors are 10 amp plugs
The light has a 13 amp plug.


the plug from the surge protector is a 13 amp plug to the wall. Out of 12 sockets on the device only 6 are in use

I used an online socket overload calculator and that says that with 2 x pc and 2 x monitor's the load is 7 amps and 1500 watts. As the rating on my surge protector is 10amp 2500 watts Can I assume i am well with in my max load on the socket and is perfectly safe and suitable for my use.
 
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I'll repeat that the fuses in plugs are there to protect the cable. If there is fault in the equipment which draws a high current then it must be the fuse that overheats and not the cable: Fuses overheat and burn out, but that's OK because it happens within a ceramic cartridge. Those monitors with 10A fuses and the light with a 13A fuse will need to have thick cables - around 6 or 7mm or more. If not it would be best to fit 5A or 3A fuses.

EDIT -> On reflection I'm wrong to suggest that cable thickness is a guide to current capacity because it depends a lot on insulation. But there are thin mains cables which are not suited for 13A loads.
 
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just checked the lamp...the plug is a 13 amp but the fuse inside is actually a 3 amp, the plug may have been changed at some point, I didnt buy it I got it off the daughter a while back
 
Most people don't. Most people don't check the pressures on their car tyres either (I know that's different but maybe you get my point).
Both those PSUs have mains cables that can easily supply more than 13A so they will likely have 13A fuses fitted. But as you can see the PSUs themselves are rated at 1.6A and 1.5A. There's certainly no need to lower the plug fuses.
My concern was only if you had equipment where the fuses were 13A but the cables were not capable of supporting it. This HAS happened to me before with things I have purchased and so I changed the fuse.
I'm sure you have heard about people buying these so-called hoverboards and in a few cases fires have started? Again that's different because its due to the battery but my point is that when it concerns your house and your family it's not always a good point to put 100% confidence in the manufacturer/supplier to ensure that the product is as safe as it should be.
 
therealdippy said:
Most people don't. Most people don't check the pressures on their car tyres either (I know that's different but maybe you get my point).
Both those PSUs have mains cables that can easily supply more than 13A so they will likely have 13A fuses fitted. But as you can see the PSUs themselves are rated at 1.6A and 1.5A. There's certainly no need to lower the plug fuses.
My concern was only if you had equipment where the fuses were 13A but the cables were not capable of supporting it. This HAS happened to me before with things I have purchased and so I changed the fuse.
I'm sure you have heard about people buying these so-called hoverboards and in a few cases fires have started? Again that's different because its due to the battery but my point is that when it concerns your house and your family it's not always a good point to put 100% confidence in the manufacturer/supplier to ensure that the product is as safe as it should be.
Click to expand...
thanks for the replies

so back to the original question....am I ok using this tower or should I send it back and get the one I i should have got which was specced at 13amp/3250 watt as opposed to the one i got which is 10amp/2500watt ;)
 
Given your current usage it is absolutely safe to use now. This has already been stated.

If it were me I'd be in touch with the seller and at least ask why they've sent you the wrong advertised part and if not happy ask for the correct one. The difference between the two items may only be something silly like the cable going to the tower is fixed 13A vs 10A kettle lead type.

Fuse ratings in devices is not a direct indication of load. I have a 10A fuse in my PC yet it only draws a shade over 300W, the PSU though is 700W.
 
Tealc said:
Given your current usage it is absolutely safe to use now. This has already been stated.

If it were me I'd be in touch with the seller and at least ask why they've sent you the wrong advertised part and if not happy ask for the correct one. The difference between the two items may only be something silly like the cable going to the tower is fixed 13A vs 10A kettle lead type.

Fuse ratings in devices is not a direct indication of load. I have a 10A fuse in my PC yet it only draws a shade over 300W, the PSU though is 700W.
Click to expand...
I have contacted the seller but they said that the rainforest are at fault as they have put it up with the wrong description. The rainforest have ignored ny attempts to contact them. All I get is that I can return it for a refund. Very nearly did return it 3 times I actually got to pressing the button to do it but then decided not too as I did not want the hassle and I had this thread going at the time, Just need to know it was safe for my usage.
 
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