AC\DC
Senior Member
- Location
- Florence,Oregon,Lane
- Occupation
- EC
Bidding a school and they don’t have the AIC rating For equipment, who’s responsibility is that generally
If you're bidding as the contractor, the Engineer should be responsible for not showing them on the design drawings. Submit an RFIBidding a school and they don’t have the AIC rating For equipment, who’s responsibility is that generally
I don't understand what a site walk has to do with verifying SCCRs?Let me know if you find out. I have been shouting it from the roof tops that Engineers need to verify AIC ratings on plan submittal for code compliance and everyone looks at me funny.
Like are engineers allergic to a site walk before doing the design work? lol I don't get it.
Everyone is trying to do it from home now.
I don't understand what a site walk has to do with verifying SCCRs?
Call the utility and derive the available SCC.How else do you get that info?
As-built lengths are good for final study results, but the initial SCCR of equipment needs to be determined upfront. This doesn't require going to the field unless the design was not based on an initial field walkthrough, which doesn't happen in my world.When drawings don't match reality... I don't know how many times our company architects would make plans that the electricians could not implement because of obstructions. If they would have stuck their head up into the ceiling and looked, or walked the hallway, they would have done a better job. Sometimes they would substitute things where it typically didn't matter (e.g. you got larger conductors because we had it and the supply house was backordered). The drawings got redlined to match reality much of the time, but the those updates never got put into the master digital drawings because they never had time to do it. After a few years, the clutter of the paper updates was in the way and they got purged.
Why would you be against an engineer visiting the site? An incredible amount of headache could have been saved on countless jobs if the engineer had actually visited them.Call the utility and derive the available SCC.
Do take-offs from the drawings to determine length and size of conductors, and calculate. What does walking the site help with?
Do take-offs from the drawings to determine length and size of conductors, and calculate. What does walking the site help with?
Because most of the time, other than initial site walkthrough for design, their are no site visits in the budget unless their is ongoing onsite construction administration in the scope of the project for the Engineer.Why would you be against an engineer visiting the site? An incredible amount of headache could have been saved on countless jobs if the engineer had actually visited them.
Especially when series rating, EE don't even need to use the length and size of conductors. To be safe, just assume no conductor and your main will have a high enough AIC rating. The rest in series will be fine. Barring that, as long as you don't over estimate the conductor resistance, close is close enough. Like load calculations, erring on the side of caution will likely be cheaper in the long run than trying to get AIC that is 100% accurateCall the utility and derive the available SCC.
Do take-offs from the drawings to determine length and size of conductors, and calculate. What does walking the site help with?
They typically give you a higher AFC so if in the future it has to be upsized the existing electrical gear is still good.On a job 5 years ago, I pumped the water out and went into a UG utility vault to get the transformer data. I guess that puts me in the walk thru if necessary crowd. I did have the AFC from the utility, but I called BS on the number they thru out. I was right, it was way off.
Typically the EC that will do the project is not even involved with the project yet. This is why we as EE and designers rely on the information from the utility for existing peak demand and AFC.Almost everything. It also helps if the contractor is already decided and you can speak to them about it while on site.
AIC from the power company for load additions or built outs when you have the service switchgear installed seems odd to me. I would rather not bother them for it. It can take way longer to hear back than just driving over to the site. For new installs, we definitely need their AIC but for existing places where you are adding load, it seems funny to wait a week or two for that information. Depending on which utility you are working I guess. Within the greater LA county area, and some parts of SoCAL, you have 6-10 utilities. Glendale, Burbank, Pasadena, Edison, LADWP, Vernon, Anaheim, etc. Granted you have to send them a load addition notice anyway.
Or you can drive an hour to the site, pull the information you need with the contractor, discuss how they want to do it, make sure you are both on the same page, put it to paper, do some math, and submit.
I run into less issues that way. But to each their own. If it has worked for you then don't worry about it. I just think walking the site makes designing easier.
Which they should not be doing IMO. I want to know what the AFC NOW., not what it might maybe possibly be in 20 years. Me and my client will decide on what we provide for future possibilities.They typically give you a higher AFC so if in the future it has to be upsized the existing electrical gear is still good.
I disagree. But that's ok.Which they should not be doing IMO. I want to know what the AFC NOW., not what it might maybe possibly be in 20 years. Me and my client will decide on what we provide for future possibilities.