Generator to run water pump 150m away, voltage drop

[lostinthelight]

Bad idea to me.

 

[Harry Bloomfield]

Quick additional question if I may... been offered another generator 2Kw, but it's only 110v.
If I wanted to use this, and hooked up a transformer with the 125-150m cable run, is there any advantage/disadvantage to doing this based on the 2Kw 230v generator we're currently using?

If you halve the voltage, you double the current for the same wattage, so if your transformer will be local to the pump/ 150 yards remote from the generator, you would need to use a cable of twice the size.

 

[Sureitsoff?]

Thanks for the advice/thoughts so far.

The pump is borehole with borehole pump, but the origin is unknown, but it's single phase 230v.

Current wiring looks like a caravan hook-up cable (if this gives an idea?)

I'll try to get a plug-in energy meter at least it will give an idea of the load when operating.
Will have a digger dig 90% of the trench to lob the cable in, so should got smoothly.

*

Quick additional question if I may... been offered another generator 2Kw, but it's only 110v.
If I wanted to use this, and hooked up a transformer with the 125-150m cable run, is there any advantage/disadvantage to doing this based on the 2Kw 230v generator we're currently using?

Thanks again.

the extra genarator is effectively a 1kw generator at 230v....

 

[ericmark]

My calculations allowing for corrected mV/A/m 4 mm² would just be within the permitted volt drop of 11.5 volt at 10 amp which is the max output of the generator for 118 meters, but I have not seen motor rating, and with an inverter drive likely you could get away with a larger volt drop.

 

[Harry Bloomfield]

the extra genarator is effectively a 1kw generator at 230v....

Er, no!

 

[SUNRAY]

the extra genarator is effectively a 1kw generator at 230v....

How so?

 

[SUNRAY]

My calculations allowing for corrected mV/A/m 4 mm² would just be within the permitted volt drop of 11.5 volt at 10 amp which is the max output of the generator for 118 meters, but I have not seen motor rating, and with an inverter drive likely you could get away with a larger volt drop.

Again looking at different on-line calculators for 118m: one says 4mm² another says 6mm², it also depends on choice of cable.

Showing the max length of 4mm² and 6mm² 3C and 2C by TLC

I don't know if it's trying to do a 3ph calculation but right through it calculates 2.2KW as 9.57A

 

[Jackrae]

the extra genarator is effectively a 1kw generator at 230v....

Please explain your theory

 

[Mr Chibs]

Assuming I could borrow something like caravan hook-up cables and connect together would this be a work-a-round test to see if the current generator would operate correctly at the distance previously mentioned. If it does, would it be fair assumption that if the SWA was similar size in capacity then all will be good? or is it not that simple

 

[ericmark]

A caravan hook up cable should be at least 2.5 mm² and 25 meters long (±2 m) but in the real world often they don't comply. But you would need 5 or 6 cables, at £49 each from Halfords, many seem to be 1.5 mm² which does not comply with BS 7671.

You are looking at around £500 for the cable, you could buy another generator for less.

 

[Mr Chibs]

A caravan hook up cable should be at least 2.5 mm² and 25 meters long (±2 m) but in the real world often they don't comply. But you would need 5 or 6 cables, at £49 each from Halfords, many seem to be 1.5 mm² which does not comply with BS 7671.

You are looking at around £500 for the cable, you could buy another generator for less.

Was only to do a test regarding running current genny with distance of cable (as there seems a little ambiguity on sizing) I'm still intending to run with SWA.

Know a few people from whom I could borrow the hook up cables for a day or so.

You are correct regarding cable size, I have a couple that are like wrestling pythons and seen some that seem thinner than straws.

 

[SUNRAY]

Was only to do a test regarding running current genny with distance of cable (as there seems a little ambiguity on sizing) I'm still intending to run with SWA.

Know a few people from whom I could borrow the hook up cables for a day or so.

You are correct regarding cable size, I have a couple that are like wrestling pythons and seen some that seem thinner than straws.

With respect,
2.5mm² = £200 (£146)
4mm² = £270 (£218)
6mm² = £380 (£288)

4mm² is a no brainer over 2.5mm² and 6mm² is about double. In the great scheme of the whole job is it worth the quibble of the larger size?

Prices are for 100m of 3 core (2 core), directly off the first hit on Google which happens to be TLC.

 

[Mr Chibs]

No you've put it like that, no.

Many thanks

 

[Mr Chibs]

Sorry, final question(s)

The borehole pump terminates in one of those IP44 16A connectors, the generator end is a standard 3 pin plug, I intend to run SWA between
(for mechanical protection only) will 2 core SWA be OK to use, or will I need the 3 core.

Also pondering if removing the UK plug socket on the generator (if possible) and replacing with something like this will be better idea?

 

[ericmark]

The borehole pump

So this is clearly in true earth, so the question is where would you fit the earth rod? At generator or at bore hole, likely the SWA is a good enough earth wire, the problem is if the outer is ever damaged then steel can rust, so I would normally use 3 core, however with a generator nothing to stop you fitting an earth rod either end, so even if the SWA does rust, it would not matter, it would still be protected.

But the point is why is the generator so far from bore hole? We still don't know, so what you are asking is for some one on a forum to design a system without knowing all the facts, the person who should decide how to earth and what cable sizes etc, is the one who signs the installation certificate. And that person will have seen exactly what is being done and why.

Likely 2 core with a earth rod either end, but I am not signing as the designer.