I'm putting together a load sheet for our public utility and I'm
collecting up all the devices that consume electricity and making a
table that shows each device. In NJ JCP&L uses what is called a load
sheet which is in my opinion wholly inadequate to develop the necessary
amps required for a property. An example is they ask what is the
largest horsepower pump that will be used. Well for our projects,
their may be a half dozen pumps, up to 15 A/C compressors etc. We do
big projects, the one I'm working on will most likely require 3000 amps
and JCP&L is not sure how to deal with this other than to say 3 phase.
Of course 3 phase is about 5 miles away, so we have to think outside
the box.
My question is this.
When listing the equipment and it's amperage (which is being provided
by the individual contractors), is an amp always an amp? What I mean
is if I have an A/C condenser rated at 24 amps and I know that device
is a 240 volt device does that have any special meaning to the public
utility? Or does it mean that if it were a 120v device it would have
been 48 amps?
My HVAC contractor has given me a list of equipment mixed 120 and 240
volt that adds up to 826 amps. Do I need to be concerned as to whether
it is 120 or 240? The electrician has installed a 1200 amp service for
the main house, but he has also installed an additional 800 amps in
seperate panels in two out buildings. We are currently fighting with
JCP&L that the 167KVA transformer is wholly insufficient. My
understanding is that a 167 gives 600-800 usable amps and that it may
be able to operate up to 1000 amps.
Our determinations are that we will need 1,200 amps for the house, 800
for the outbuildings, another 1,000 for the outside pumps, ponds,
irrigation, site lighting etc and another 800 amps for a large 24 stall
barn which will be installed. This gives a potential for 3,800 amps
total based on paper. Now I know that JCP&L does a calculation whereby
they know that full amperage draw will never happen, BUT in these large
scale residential properties (31,000 sq ft) It is possible that at
times (Parties), that most of this equipment is running. We are no
longer living in a "dont' have something plugged into every outlet
environment" It would happen that all 15 HVAC zones are running during
a large gala while the pond aeirators and fountains and pool and
jazuzzi pumps and significant lighting are all operational at one time.
JCP&L needs to understand this.
So, is an amp an amp when it comes to these calculations?
Thanks for your help. Oh, don't worry, I'm not trying to replace good
engineering practices, I'm just trying to make sure that my electrician
and power utility are taking everything into consideration. They still
make all the calls, I just need to be an enlightened GC.
- posted 16 years ago