Need a program that can calculate electrical loads


RL-inc
 Share

Recommended Posts

A good friend of mine is a supervisor electrician and wants to be able to have me help him with electrical load calculations.

He will do all the heavy mental lifting I just want to be able to use CA to create the layouts for him and then calculate the electrical loads.

 

does anyone know of a program that I can use with CA that I can input the loads for certain fixtures and them create total load calcs?

Link to comment
Share on other sites

FYI:

Residential electrical codes are not concerned with small appliances and lighting loads as they may not be representative of future loads and not all loads would be used at the same time.  There are also specific requirements as how to handle heating, cooling,cooking, and motor loads. All is explained in the electrical safety code. If your friend is a licensed electrician he should be aware of this. There is generally no need to list small loads as they handled within the code calculations. The larger item load  requirements  are specifcally listed within the code.

 

As to CA, it has no capabilities in this area.You would be better off using a external SS in the format recomended by the IRS code, then cut, paste into CA.The code is not difficult, but unless you take that the time to read and understand, I wouldn't go there. There are safety considerations there.

 

Other then that, most just list the large loads by cut/pasting a SS from Excel, as required by the code and let a licensed electrician complete the calculations and size the circuit protection.

Link to comment
Share on other sites

The guy I am talking about is a supervisor electrician in Oregon and is one of the best tradesman in any field I know.

He does all his own load calculations and what I want to do is have the ability to help him with the quality of his drawings and load tables.

He will do all the calcs and checks, I will be doing the layouts and drafting.

That said, as we discussed it tonight I started thinking that if CA had the option to specify the electrical load in amps or watts for a certain fixture in a DBX, that column could be added to the electrical schedule and then each column could be tallied and the total load for a building could be calculated.

CA wouldn't have to determine the loads for each fixture- that could be added by the user when the spec's for that fixture were established.

Then just set up the schedule to complete the calculations.

May be a nice feature to add for X8.

Link to comment
Share on other sites

May be a nice feature to add for X8

 

Rob:

 

I wouldn't hold my breath

 

X8 beta has started

 

besides CA has shown no inclination to go in this direction

 

Chief doesn't do MEP very well

 

nor does it do BIM inter-operability

 

probably best you can do is place items in Chief's Electrical schedule

then export to Excel and go from there

 

Lew

Link to comment
Share on other sites

The max load on any circuit is P=IE so for a 120 Volt xs 15 amp breaker = 1800 watts before the breaker trips or the 14 gage wire frys. Same for 12/2, 20 amp. Code defines system architecture. Not sure what you`re wanting CA to do that is not already simply defined.

Been a while since I did Sparky stuff think that's right.

Link to comment
Share on other sites

Another down and dirty way to keep a cumulative total would be to use the price column in the material list as your electrical load (instead of price) - these will auto add.

AS I said REALLY down and dirty - but will save you doing the math.

Link to comment
Share on other sites

Electrical load is in watts not amps and listing an amp rating for a fixture does nothing to determine it. 

 

Based on the OP I have a feeling the electrician is looking for CA interface software that does “load calculations” to determine impedance and whether lights will flicker when the HVAC is turned on, etc, due to voltage drops. Perhaps a simulation plug-in that does load analysis based on statistics from load field meters. With the green and energy efficient movement, IECC 2012, came a need to know for CO2 emissions, utility bills, sizing of solar arrays and storage batteries. See sample report below, NREL has been behind it for one developing load data to design to embedded in simulation software. Add a NREL SAM or PV Wattts plug in would be useful.... Add DC vs AC, inverters, KWH’s, it can get complex. 

 

If you looked at the HVAC thread Rob linked to, there the OP is asking for the same thing, to calculate or simulate HVAC loads. If one could do both electrical and HVAC in the CA model that would be very powerful. I’m not sure why CA does not offer plug-ins or work benches, I for one would be willing to pay the price for the additional licenses.

 

As far as plumbing, in my mechanical HVAC design CATIA software I use it has a “tubing workbench” that automatically routes to “smart” hardware like clamps, b-nuts, sleeves, with nodes programmed in them. There is an additional charge for the work bench. I pick the clamps and the software shows me several routes I can choose from. It has an electrical work bench that does the same. The software is "smart", has bend radius, max distance between bends for tube bending machines, different end types(square, flared, etc), materials I can assign, etc. Although it can be a PITA that be nice too.

 

Another would be Finite Element Modeling (FEM) for structures. 

 

It is a pain to export CA to other software’s. It is useful for design integration and communication purposes to do all design analysis in one model. That is where most industries have headed. 

 

http://www.nrel.gov/docs/fy06osti/38601.pdf

 

It would be nice to show clients empirically simulated bar or pie charts, based on averages for a family of 2, 4, 6, etc

 

post-5962-0-48313600-1446898293_thumb.jpg

 

post-5962-0-99303700-1446898299_thumb.jpg

Link to comment
Share on other sites

Terry:

 

yes, if Chief could model the electrical plumbing and HVAC runs with all the associated elements

and then use BIM inter-operability to communicate with dedicated software for handling the loads

and collision detection etc

 

unfortunately, Chief is not capable of doing this yet

 

 

Lew

Link to comment
Share on other sites

I have been working in a BIMS environment for global fortune 500 companies for around 20 years now. I seen the transition and what it is capable of, and it's issues. We use Enovia which is state-of-the art. Just last week I was dealing with routing issues on a HVAC design I am trying to release and get signed off by 12 other disciplines on a big power generator plumbing. It has a history of "concurrent engineering", "Design Build" "Integrated Product"  and a few other buzz words software sales guys come up with. In reality for large companies that "route" design packages to multiple down stream reviewers it has it's benefits compared to back in the day when the designers should "walk" the package around having taken responsibility for "Integrated Design" and coordination. Back in the day that did not happen as well as today, granted, not all is contributed to BIMS software, much still lies in the hands of the designer to do and understand how to communicate. 

 

Along with BIMs is "Relationship Design" that handles clashes or "collisions" that's another animal but based on software model management that helps manage designers that may not be communicating. 

 

I would not let life cycle management software such as BIMs stop Chief from offering the licenses now. There will be a lot of complex learning curves in big construction companies transitioning to BIMS, over kill at the home level, it is just software the Architect/ designers still have to pull in the right expertise and do the coordination. 

Link to comment
Share on other sites

Electrical load is in watts not amps and listing an amp rating for a fixture does nothing to determine it. 

 

 

 

Huh?

 

P=I x V.

 

It doesn't matter whether you calculate your circuit load based on amps or watts. For lighting circuits it may be more convenient to use watts because that's how lighting fixtures are labeled, but for equipment circuits I find it's easier to use amps.

Link to comment
Share on other sites

Huh?

 

P=I x V.

 

It doesn't matter whether you calculate your circuit load based on amps or watts. For lighting circuits it may be more convenient to use watts because that's how lighting fixtures are labeled, but for equipment circuits I find it's easier to use amps.

 

If you are calculating amps you are calculating flow (like water flow) per unit time of electrical charge. That is not a "load". 

 

OP says this, 

 

 

A good friend of mine is a supervisor electrician and wants to be able to have me help him with electrical load calculations.

He will do all the heavy mental lifting I just want to be able to use CA to create the layouts for him and then calculate the electrical loads.

 

does anyone know of a program that I can use with CA that I can input the loads for certain fixtures and them create total load calcs?

 

 

 
Perhaps he did not understand or miscommunication with his electrician and used "load" inadvertently. As I said above "power consumption" is often referred to as "load" in watts but, not to be mistaken with Impedance which is " electrical load" in resistance and the unit is OHM. Impedance differs from resistance because it has magnitude and phase, resistors only have magnitude. Impedance determines if lights flicker if a high load appliance comes on relative to a power source, therefore it is the cumulative 'load' on a circuit including both lights and appliances and anything else on the circuit. Impedance measures the difference in amplitude between amps and volts. In parallel circuits it does not add up as in a spread sheet, it is more complicated than that, in fact, it is complex and a program or plug-in would be nice.
 
The Cartesian formula is,
 
Z = R + JX
 
R= Resistance
J= Current type unit
X= Reactance
 
 
 
Link to comment
Share on other sites

 

 

 
Perhaps he did not understand or miscommunication with his electrician and used "load" inadvertently. 

 

Only the OP can tell us for sure, but yes, I think you're interpreting his request too literally. My take on his request is that he's looking to provide a calculated amperage total so branch circuits can be sized properly. I'm sure your familiar with the NEC section that says something like "branch circuits shall be rated in accordance with the maximum permitted ampere rating...". Conductors are also rated by ampacity - so again, you want to know how many amps your placing on the circuit so you can size the conductor (and the breaker) properly.

 

Of course, I could be totally wrong about what the OP is looking to achieve. Maybe he's dealing with systems over 120 volts and conductor runs greater than 1000 feet.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share