Hedge trimmers, generators and invertors

[The Natural Philosopher]

You can't do that. Over time he top becomes very ragged with stumps everywhere. Now nd again upo have to cut the stumps couple of inches lower to get a decent top growth of new stuff.

[Owain]

How about transforming up to 400V + at the house end and transforming down at the trimmer? Say by using 2 site transformers in reverse?

Owain

[manatbandq]

Not if you want it to look nice afterwards, not after seeing the fecking mess they make of the hedges round here.

MBQ

[Lobster]

Ah! So *that's* why the hedge between my house and the neighbours is now approx 12 feet thick and occupies most of our respective front gardens... ;-)

[Dorothy Bradbury]

As in using 110-220V transformers in reverse?

I have several problems with that... o Is the transformer capable re 240V converted into 480V

---- those are RMS voltages, peak voltage is yet higher o Disconnect

[Dave Plowman (News)]

I'm not well up on the designations, but the rubber stuff (TRS?) puts up with enormous abuse on location filming.

[meow2222]

If you apply 240v to a 110v winding or 480v to a 240v winding, both transformers would rapidly fry. Current goes up non-linearly and heavily as rated v is exceeded.

There is an easier option, just measure (or calc) the running V drop and add a boost transformer at the supply end to add the 8v or whatever onto the 240v supply. Then when motor running it sees

240v.

This would be done with an 8v (etc) transformer, with the secondary ptu in series with the mains feed. 8v 3A is only 25w.

NT

[meow2222]

this would also permit use of lighter 1sqmm flex if preferred - or even

0.5sqmm.

NT

[Andy Champ]

Actually, it's quite easy. A hand powered winch on a trolley - don't try to winch the cable in, push the trolley and wind as you go.

Andy

[Derek Geldard]

Tough Rubber Sheath.

And other work situations.

DG

[The Natural Philosopher]

Indeed. They cut back a massive laurel hedge in the next village to put in a footpath. About 3ft back..its just about grow over the bare poles again.

[tinnews]

Why the worry about voltage drop? A hedge trimmer is, at the absolute most, say 1000 watts which is 4 amps - and that's probably not continuous.

Even if you lost, say, 30 volts, (which is most unlikely) the hedge trimmer will still function reasonably well. As long as the circuit is protected by an RCD the safety aspects are handled by that.

[tinnews]

Why? Even if you drop lots more volts than you're "supposed" to it'll work fine.

[tinnews]

Far too clever, just run the trimmer at 8 volts below the optimum voltage, it'll work fine.

[meow2222]

Yes, just a question of performance (or performance to weight ratio), which counts when you've got half a kilometre of hedge. Boosting to 250v would be a bit naughty.

NT

[tinnews]

I really don't believe that the likely voltage drop (probably at most ten volts or so at the end 200 metres of even quite lightweight cable) is going to have even a noticeable effect on the performance of the hedge trimmer.

[The Natural Philosopher]

Noticeable yes. Significant no. Easily catered for by starting with a more powerful one.