Been at a call out in a block of flats where on ocasions there has been a power surge.On further investigation the culprit being a slack neutral on the main incomer coming into the building.
Now i understand that the loss of a neutral can create a voltage of 415V but can anyone give me a proper...
The prospective short-circuit current between line and neutral is measured at 900A. The maximum balanced prospective short-circuit current level between lines, as a rule of thumb, can be assumed to be approximately:
A: 0.9 kA
B: 9 kA
C: 90 kA
D: 1.8 kA
:banghead:
Hi all I passed my 2391 about 6months ago and thought I was flying, I know test procedures & how to carry out the tests like the back of my hand and I fully understand any results I get and how to rectify or diagnose any faults in a electrical system.....but then again I have only tested...
p11jor
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2391
current
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supply
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Hi all
came upon a 3 phase + N supply into a domestic property with only one of the phases being used to feed the c/u.
On the cert do i put down 3 phase or single phase
thanks
john
I want to introduce an IR heating system into an existing split load CU. It is supplied at the moment by 1 phase of a 3 phase input, controlled by a 60A main fuse and a 40A meter. The 5 existing circuits are 2 x 32A ring mains, 2 x 6A lighting and 1 x 16A water heater.
The total wattage for the...
Hi
Quick question about a system a user wants who has 3-phase electricity. If we install a 4kWp system onto one phase, when it is generating more power than is being used by that phase, will the other phases consume that power, thus slowing/stopping the meter, or is it lost back to the grid...
PvNewbie
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3-phase
consumption
energy
meter
phase
phases
power
solar
Morning guys,
I'm new to this so bear with me!
I have two 16a single phase machines that I want to supply with a single cable. I want to use one neutral and earth for two separate circuits. Is this possible? I seem to remember when N is a load carrying conductor, combining two loads could burn...
i am sepperating a small unit from the main building next door. the owner wants the said unit on own supply and on own meter to resell the electricity , i have seperated the circuits involed , a 10amp lighting cct, a 32 amp ring final and a 3 phase 32 amp isolator . i have placed the ccts...
hi,
Haven't done a three phase systems and have always assumed that staying under 16amps per phase can be fitted, and DNO informed afterwards.
Is that correct or does the DNO have to approve prior to installation.
thanks in advance.
RN
Noddy67
Thread
commercial
fit
inform
light
phase
phases
still
three
hi all
ive been asked to wire some high bay lighting in a unit from a tp+n c/u.
my question was as its accross all 3 phases what do you do about the switch end?
i dont like the idea of 400v in a metal switch box.
ive got 4 rows of 400 hids and want them switched in rows.
ta all
vitoboy
I have installed a 16a 3 phase extract fan, when doing my testing after id finished i had 403v between phases, boss thinks this is ok but i think its a bit low, anyone?
The company I work for sent out some guys to connect up some temps through a 3 phase meter. Now the circuit was fed via an existing board with a 63A breaker and the existing board was backed up by a 160 amp mccb.(plus an rcd for the sub-main). The 3 phase meter so I have been told went up in...
Does anyone know what the tripping times for an Wylex bs 4293 100ma type s RCD are? Ive been searching the net and just keep getting more and more confused about this i know an bs6009/9 should trip within 130ms-500ms but cant make headway for the tripping times for an older bs4293 rcd.
Hi Guys
Just wondering if anyone could help me with this. I have to submit a quotation for a job but its larger than I have done before. The electrical AC side I havent a problem with its more the PV spec.
So here is what I'm working with-
The contractor shall allow for the supply and...
erf151an001
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electrical work
installation
panel
phase
phases
shall
Hi, I'm due to install a 3.6Kw system on a property with an existing 6Kw Wind turbine.
I have applied for it with the DNO because it already has the 6Kw wind turbine.
The installation is 3 Phase and I intend to connect the PV system to a different phase to the wind turbine.
Has anybody had...
just about to price my first 10KW 3 phase install and was wondering if the first 4Kw are at 43.3p and the remaining 6Kw at the lower rate or would the whole system be charged at lower rate? If as I suspect the whole job is at the lower rate then a 5Kw system would never be viable (for future...
An ex farm that i visited today would like to install a 3.6kw system feeding into a single phase which is currently supplying an outbuilding.
The remaining 2 phases supply the house,
Assuming that the DNO is happy with the imbalance, if we installed the system would the energy generated on this...
Hi guys just need some help with 3 phase.I have done some theory on it a while back but not alot.So I get the fact there are 3 phase's and a neutral The three phases are colour coded and go to three separate parts on the 3phase db,Is this correct?What next? For the final circuits?Cheers for any...
Im doing my 2391 course and it was quickly mentioned about symmetrical fault current when talking about PFC testing.
It was just mentioned and not explained so can anyone explain what this means.
My first thought is that 3 phases shorted together would cancel out and leave 0 volts??
But...
daveede
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current
double
explain
fault
fault current
phases
please
when separating 13amp sockets on different phases by 2/2.5m
-the only concern is physical separation of the sockets and not leads and appliances?
am i right in thinking any risk to customers/users from appliances on different phases is very small?
davelerave
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appliances
different
earth
label
phases
right
separation
small
socket
sockets
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