Portable Generator

Ben Starr · Mar 28, 2013

I need some advise with portable generator earthing. We use 1Kw Honda generators on about 20 small buildings. These are of plastic outer construction and we use them to power these small buildings for florescent lighting and a couple socket outlets via a small DB. We install a link between the MET and Neutral before the RCD so that it will operate. I would like to know your thoughts on how we should provide an earth? Earth Rod?

shocking_eg · Mar 28, 2013

TT the generator.

most have earth rod connection points anyway

then use a 100ma RCD upfront for all circuits. then additional protection where required

test electrical · Mar 28, 2013

Leave the link in and put a rod in as well and use a 30ma RCD as this is a temp system.Do a ZE test and you should be well below 0.35 but the rcds will trip due to volt drops but would get that with samll sets any way.

La Poste · Mar 28, 2013

Why would the rcd's trip due to volt drops?

test electrical · Mar 28, 2013

Them small gens go under load they volt drop and speed up,its the movement and the shagging around they do knocking of the trip.So but a broad over the top of it a block on it hope for soft ground.But they always knock themselves off.

GLENNSPARK · Mar 28, 2013

this should do the trick...

View attachment untitled.bmp

44ALLAN · Mar 28, 2013

test electrical said:
Them small gens go under load they volt drop and speed up,its the movement and the shagging around they do knocking of the trip.So but a broad over the top of it a block on it hope for soft ground.But they always knock themselves off.

I neva got taught that at college...........they told me it was an imbalance that caused Rcd's to trip not gennys going faster on hard ground !!

You live and learn as they say !

test electrical · Mar 28, 2013

watch out using a hammer drill near a DB, never in a hospital RCBOs go mad.And you could get in a lot of ****

test electrical · Mar 28, 2013

watch out using a hammer drill near a DB, never in a hospital RCBOs go mad.And you could get in a lot SH-T

44ALLAN · Mar 28, 2013

test electrical said:
watch out using a hammer drill near a DB, never in a hospital RCBOs go mad.And you could get in a lot of ****

I'll remember that next time I'm using the hammer drill on ward 7 !!!!:lol:

Engineer54 · Mar 29, 2013

A 1KW portable generator will have a floating earth arrangement, no voltage regulator and the worst thing you can use, for many types of appliances. They are basically made for temporary site work, where only a bit of lighting and small drills/tools are to be used!! It's basically pointless trying to treat these tiny portable generators as more than what they actually are, by installing earth rods and the like!!