Extension Cord Advice

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tdgeek

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#306483 27-Jul-2023 10:54

I'm not electrically minded so bear with me

I want to get a paint sprayer for the fences, and other outdoor stuff. I know that the longer the cord the voltage drops and the device can overheat

I have a longish heavy duty extension cord, it has a light at either end. IF I needed a few extra metres, can I put a normal extension cord first (as the voltage drop will be low) then the heavy duty cord? If this was an option I would monitor the device temp to make sure it wasn't getting any/much warmer, and I would do a 60 second stint then a 60 second break to help mitigate overload. Or get another heavy duty cord to join to the other one. Or just buy a longer heavy duty cord that meets my distance?

I also have a corded linetrimmer that I'd like to use on the berm so that would mean, plug the heavy duty cord into the house then the line trimmer that has a built in longish cord

I could get a battery sprayer, but they seem to not last long, Ozito seems an option but reviews seem not great. Plus these wont be regular tasks so no real need to invest high for rare usage

Thanks

(I will do some measuring later today re distance needed)

shk292

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#3108713 27-Jul-2023 10:59

What's the power rating of the paint sprayer? I wouldn't expect it to be very high, so the load (and therefore lost power) in the extension cable shouldn't be high.

tdgeek

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#3108719 27-Jul-2023 11:12

shk292:

What's the power rating of the paint sprayer? I wouldn't expect it to be very high, so the load (and therefore lost power) in the extension cable shouldn't be high.

Couple of Googles show around 460W to 550W, could not find any amps if that matters, in fact I cannot tell if they have a long cord included or just a short card

shk292

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#3108727 27-Jul-2023 11:21

So, that's an absolute maximum of 3A depending on a few factors such as load type, on a 240v supply. Given all extension leads sold in NZ should be rated at 2400W or 10A, this won't be a problem. Power loss in the cable is related to the product of current and length, and at 3A you'd need a very long cable to cause a problem. Similarly, a short "light duty" cable won't be a problem provided it's approved for NZ use and has 10A capacity

tdgeek

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#3108732 27-Jul-2023 11:27

shk292:

So, that's an absolute maximum of 3A depending on a few factors such as load type, on a 240v supply. Given all extension leads sold in NZ should be rated at 2400W or 10A, this won't be a problem. Power loss in the cable is related to the product of current and length, and at 3A you'd need a very long cable to cause a problem. Similarly, a short "light duty" cable won't be a problem provided it's approved for NZ use and has 10A capacity

Appreciate that, thank you.

johno1234

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#3108735 27-Jul-2023 11:41

Agreed with the above.

Also, any power loss in a segment of cable should be a function of the length (i.e. resistance) of that cable, regardless of its position in the transmission line, as the current is the same anywhere on that line (assuming no leaks!). So it wouldn't matter if the lighter cable is at the beginning or end.

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#3108899 28-Jul-2023 00:12

A timely topic as I just watched the below John Cadogan YouTube video yesterday about extension cords.

I bought a new compressor about a year ago and I did note its annoyingly short cord at the time, but to be honest I would never gave given it a second thought about using an extension cord (or the quality/rating of said extension cord). Fortunately I have a 20 metre air hose and have only used it within the garage so far, but at least now I know for future reference.

[EDITS: trying to get the damn youtube video into the post lol]

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tdgeek

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#3108917 28-Jul-2023 07:16

Bit of a humourous side comment, back in the day when I was poor and we bought a handyman special, I made three extension cords, meticulously making sure the colours of the 3 wires matched

They all worked, happy me. But if I put two of them together, they didn't. Needless to say I am NOT a number 8 wire guy with electricity, but I'd be keen to know why two of the cords were seemingly incompatible? I vaguely recall later in life that colours were changed?

mdf

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#3108992 28-Jul-2023 09:57

Wheelbarrow01:

A timely topic as I just watched the below John Cadogan YouTube video yesterday about extension cords.

I bought a new compressor about a year ago and I did note its annoyingly short cord at the time, but to be honest I would never gave given it a second thought about using an extension cord (or the quality/rating of said extension cord). Fortunately I have a 20 metre air hose and have only used it within the garage so far, but at least now I know for future reference.

^ Great video. I'm currently in the midst of renovating. We had no power in the renovated area and even 40m of air hoses wasn't long enough (2x 20 > 1 x40 IMHO, even though you do get some extra leakage at the join). I was leery about doing it, but eventually decided I had to use an extension lead, but did make sure it was an extra heavy duty 1.5mm^2 one. Which according to that video, is probably the least bad way of doing it. This was only with nailers though so pretty light usage.

FWIW, the next time you have any electrical work done, ask your sparky about a dedicated 15 amp circuit + socket in the garage. It was pretty cheap for us when we were having some other work done anyway (though then the 15A extension cable was about that price again). It is intended for a 15A welder (purchase pending) but I tend to use it for the compressor when I'm doing anything air-intensive like spraying. Almost certainly overkill, but make me feel better about worst case scenarios.

Bung

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#3109010 28-Jul-2023 10:22

I don't know why the video introduced 15A plug ended cords into the mix considering that extra heavy duty 10A cords are available with 1.5mm conductors. Heavy duty now just means that the cord has a thicker sheath.

When garages tended to be separate from the house apparently it used to be quite common for big chest freezers to suffer from brown out because the wiring was already undersized for much more than lighting and a door opener.

Wheelbarrow01

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#3109435 28-Jul-2023 21:26

mdf:

FWIW, the next time you have any electrical work done, ask your sparky about a dedicated 15 amp circuit + socket in the garage. It was pretty cheap for us when we were having some other work done anyway (though then the 15A extension cable was about that price again). It is intended for a 15A welder (purchase pending) but I tend to use it for the compressor when I'm doing anything air-intensive like spraying. Almost certainly overkill, but make me feel better about worst case scenarios.

When I had my garage rebuilt 3 years ago (EQC), I went a bit overboard with electricals, so I already have an over-spec main lead from the house with plenty of spare capacity at the sub-main switchboard in the garage. It also has one of those big PDL dedicated caravan sockets (like the campgrounds have) - 16 amps I think? That could have a multitude of uses I guess...

At the other end of the house I also have a 15 amp 3 pin outdoor socket for the spa pool, so I could also use that if I had to.

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#3109462 29-Jul-2023 08:58

dont forget the RCD...plug it at the source of power.

and good luck with the trimmer......ive cut/nicked many an extension cord just by getting to over excited with the trimmer... (and after having to re splice a few times, I decided I need to be "slower").