chopped mower cable

[topbanana]

my mate, no honestly, has cut through his mower cable and wants to reconnect.
i gave him a plastic connector block as a temp measure, but for a more permanent job, with added benefit of being able to hang the cable aside from the machine, he wants to fit a connector plug and socket, as supplied by wickes.
when purchasing i found that there was specific points for connecting neutral and live on each, but the male and female could be fitted with one of them 'upside down' meaning the live would connect to the neutral.
i've checked another machine to find the same situation.
am i to assume this is not a problem??

 

[mapj1]

If it is a modern product with a 2 core flex, then live and neutral are interchangable. This is one of the many requirements of modern product legislation - after all it could be sold in Europe, where the 2 pin sockets are reversible.

 

[Steve]

And here was I thinking a lawn mower just had a simple motor that goes backwards if you reverse the polarity I didnt think lawn mowers had any electronics at all, just a switch and a motor (aside from overheat cutout etc!)

 

[topbanana]

cheers mike you set my mind at rest.

 

[mapj1]

And here was I thinking a lawn mower just had a simple motor that goes backwards if you reverse the polarity I didnt think lawn mowers had any electronics at all, just a switch and a motor (aside from overheat cutout etc!)

Er it usually doesn't have much more inside, but please realise that an AC motor goes round the same way, even if you change over the leads to it - it is an AC motor after all. (Alternating polarity anyway..)
(if Crofty was right you'd have to swap between cutting the grass backwards and forwards 50 times a second.. )

All I was saying was that since the 1970s, all double insulated appliences has to have equally re-inforced insulation on both the live & neutral sides of the internal wiring etc. Also most modern hand held stuff is made double insulated, rather than with an earthed metal box, for the same "one size fits all countries" reasons, so often the earth core is not needed either.
Hope that clarifies what I was meaning.

 

[Steve]

I was thinkin that as i clicked submit, mike, about AC, i must have always used DC motors in physics lessons!

What about those commercial xpelair extractor fans with control panels to alter speed, direction and (something else, cant remember what!) How does the direction control work? It only looks like a 3c flex between the fan and control panel (what i remember, its been a while since i saw one). Do these use DC motors?

 

[jtaunton]

The AC will go to (possibly a transformer and then) a rectifier. Four diodes arranged in a diamond. These will then give a DC + and - output. This can be polarity-switched to give your forward and reverse.

I'm not 100% sure on how AC motors work, but they may just be DC motors with an internal rectifier.

 

[pdcelec]

Inverters could be used which may incorporate burst fire thyristors and big diodes. The inverter converts the ac to dc, changes its characteristics to what you require and then converts back to ac ready to be used.

 

[Spark123]

It depends on the type of motor. A universal motor (series) which has a wound stator and wound rotor can be reversed by reversing the polartiy of stator or rotor (but not both).

 

[ban-all-sheds]

I'm not 100% sure on how AC motors work, but they may just be DC motors with an internal rectifier.

http://en.wikipedia.org/wiki/Electric_motor

 

[securespark]

Best to replace the flex altogether. If not, use a waterproof connector - Greenbrook do one.

The two-piece connectors of which you speak are not strictly waterproof - they are not really designed to trail - they are meant to be off the ground.

 

[ban-all-sheds]

I've used one for years - never had problems. They are reasonably damp proof - nobody mows in the rain, or when the grass is seriously wet, as it just clogs up all the time.

As long as you've got your RCD, the risk of chopping off bodily extremities with the whirling blades is probably higher than any electrical ones...

 

[jtaunton]

I'm not 100% sure on how AC motors work, but they may just be DC motors with an internal rectifier.

http://en.wikipedia.org/wiki/Electric_motor[/QUOTE]

Live and learn....

'Tanks !