In our office - we have an electrical outlet (large 3 prong
electricians just installed). It is supposed to be 208 Volts...
we were having some problems with our equipment, so I ran a multimeter
on it - and when I hook up the hot and neutral to the meter (analog
type), I get the correct reading of 210volts +/-.
when I connect to the hot and the GROUND I get 120 volts... is that
correct, or does the electrician need to come back out? I thought hot
and ground should also produce the 210 volt reading...
Thanks in advance!
i have been thru this in malls, check the volatge at different times
of the day, i found it swung wide, and caused great machine troubles.
floating neutrals and a idiot electrician.
i finally gave up and dumped the customer, the hassle just wasnt worth
commervcial buildings have wierd wiring troubles
OK. This from a 3 prong electrician. Presently in Middle East where
all domestic electricity tend to be 3 phase and 230 volts phase to
Forgetting all that, but boy those plug in 230 volt appliances often
heat up fast! Would you believe a 2200 watt 2 litre kettle!
We are without all the info to go on from the OP and
presuming this is in North America or somewhere similar?
But as mentioned what is it for? What is the equipment to be plugged
in? Does it require a 3 phase supply? The 208 volt number sounds
suspiciously like the voltage between two phases of 3 phase supply!
Howerver if the electrical supply in the environmernt mentioned
requires to be similar to that in a typical North American domestic
sitaution. (But not Europe or elsewhere), what you have installed
'may' be OK.
To the OP. Domestically and in many 'light' buildings there are
typically a three wire supply. (And a ground wire; ignore the ground
wire although it is essential for safety, for a moment).
Between each of the 'outer' wires or legs and a centre point
(neutral), which if present but may not be required in this case, is
usually a white wire which is at approx. zero volts; there should be
about 110 to 125 volts.
One way (although not completely correct) to think of this is to
imagine a red wire leg being at plus approx 115 volts and a black
wire leg being at minus 115 volts. So between the two there is approx
115 + 115 = 230 volts.
If between the two outer wires there is approximately 210 to 230
volts. This could be very similar to what an electrical home clothes
If you have a 3 wire socket, installed correctly and it is correct for
the equipment to be plugged into it requiring 230 volts 'single phase'
the third pin should be the safety ground and your measurement of
approx 210 to 240 volts between the two live pins may indicate all is
A few other questions! Is this a dedicated circuit, for a special
purpose machine? Does it have a separate circuit breaker of the
correct rating to match the gauge and type of wiring used (not the
machine itself)? Or ist a circuit shared with other outlets/sockets?
Just telling someone to install a 230 or 208 volt outlet without other
specifications may not have been sufficient info!
Rather like telling someone they need a new battery without specifying
if it is
for a boat, a heavy truck, motorcycle, garden tractor or flashlight!
Sorry for the length of this comment but the original post raises
There is _no_ neutral in a 208V circuit. Just two hots and a ground.
It's the same arrangement as a pure 240V circuit (no 120V loads) - two
hots and a ground.
A 208V circuit is derived from a 3 phase (of the right type) circuit.
It's just two of the three hots and a ground.
So, 120V between either current carrying conductor and the ground,
and 208 between the two current carrying conductors is EXACTLY what you
SHOULD be seeing.
I assume that one of the conductors is white - that's what's fooling
you. It's not a neutral. (It should be marked or taped to black or
Age and Treachery will Triumph over Youth and Skill
As others have assured you, this is normal, just as the same outlet in
your home would show 240 and 120, respectively.
It's because North American commercial properties are generally fed
with scheme called "three-phase wye" (or "Y"), about which Wikipedia
or a bit of Googling can tell you lots.
The two hots were 208V apart, and each was also 208V from ground,
well, that just wouldn't add up. (Though if the hots were transformer-
isolated from ground, then...well, no, not even then.)
Is there some *reason* you needed to test the outlet after
installation? Did your new computers just not work?
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