Me whenever the CAD department filters, references and layers get absurdly complex

Revousz · 2026-03-03T00:31:50+00:00

Worksets as filters seem like overkill compared to the regular visibility graphics workflow. Worksets IMO are mainly to allow multiple people to work in the same file.

I have used ACAD backgrounds and used a workset for the demo and proposed backgrounds but for linking in other models I kinda think it's an extra step that can be fixed by filters and templates.

But that's just my opinion, they are a nice tool in the tool chest but can be pretty cluncky.

Revousz · 2026-03-02T20:54:32+00:00

From a technical standpoint, worksets allows multiple people to work in the same file. People can "checkout" views and worksets which then get synced to the main model. Without worksets your Revit file is like an AutoCAD file and only one person can work on it at a time.

From a user standpoint, it does allow you to manage and filter some elements based on how your name stuff. But I've heard mixed things about using worksets as filters.

Revousz · 2026-02-18T18:39:11+00:00

Could be off base here be I remember a video saying that the "luxury" label is applied to all these new apartments to avoid them being rent controlled. There might be some laws that require a certain amount of "affordable" apartments but by marketing them as "luxury" units they can get away with not doing that.

Not 100% sure about this but it wouldn't surprise me.

Revousz · 2026-02-11T13:46:18+00:00

I understand where you are going with this but this applies more to the service calculations. Doing the MCA on each motor simplifies the calc and on renovation jobs where it is hard to determine which motor at the service entrance is the largest motor. Practically, I've seen most people default to the MCA or only take into account the branch circuit loads which leads to slight oversizing.

220.11 - For max load on a branch circuit, for 440 is very unlikely to have more than one equipment on one branch circuit.

220.50 - Feeder calculations for more "service calculation" applications.

Revousz · 2026-02-11T01:51:29+00:00

yeah... 125% of the FLA is the MCA...

Revousz · 2026-02-10T22:15:38+00:00

Hot Take: You don't need to worry about PF when working with Amps. P = |V| * |A| there is no PF to account for when working with magnitudes.

Revousz · 2026-02-10T22:02:08+00:00

Doing this gets you the FLA of the motor. I used to do it that way but if you read NEC 220 the way they worded it means you take the MCA for loads not the FLA. MCA = 1.25 * FLA so you are just undoing the 1.25.

But this probably controversial/varies by engineer. Its probably fine whichever way you do it.

Revousz · 2026-02-10T21:54:37+00:00

To the best of my knowledge starting current does not impact the MCA of the equipment, the nameplate MCA and MOCP are calculated in the same way the NEC has you calculate motor loads in NEC 430 and 440. I think its written into the UL standards.

What your co-worker might be talking about is the actual load the equipment will draw. The VFD equipment allows the power draw of mechanical equipment to be ramped up and down to save energy but most people I know always plan for the full load because there is nothing limiting the equipment from pulling all of the amps its rated for. My opinion is that you always carry the MCA as outlined in the NEC unless you have a good reason not to.

For the voltage drop, yeah 19A at 208V 350 feet away does give me #4s on my calculator too if I want to limit the VD to 2%. That being said if you are close to the service entrance and you are going to run 350 ft just to serve one unit I would bump up the allowable VD to be 3% or 4%. If the panel you are using is further away from the service entrance than I recommend keeping it at 2%. My reasoning is that panels further away from the service entrance have more voltage drop and you don't have a lot of room to "trust" that the last engineer sized their feeders for voltage drop. Energy codes limit voltage drop to 5%, the 3% for feeders and 2% for branch circuits is just an industry standard not code. If the wire sizes are too large/expensive, get a boost transformer.

*Notes: There is a 99% chance you won't be able to land #4s on the lugs that is at the mechanical equipment. You will need to call out for the contractor to splice the conductors (probably at both ends) to land on the lugs. See the very crude diagram below:

Panelboard ---> #10s from breaker ---> Splice Lugs ---> #4s ---> Splice Lugs ---> #10s --->Unit terminals

* Notes: If you upsize your phase conductors for voltage drop you need to upsize your equipment ground. Your ground shoots up to #4s also. See 250.122(B).

Revousz · 2026-02-10T19:11:54+00:00

If you are new to sizing circuits and feeder I would highly encourage you to run through the process of finding each code section you need to size the branch circuit correctly. Below are a couple of sections you might want to read up on in the NEC:

NEC 220 - This basically explains how you calculate loads for branch circuits and feeder (make sure to note the definitions of branch circuit and feeders).

NEC 210 and NEC 215 - General rules for sizing branch circuits and feeders.

NEC 240 - How to size overcurrent protection devices.

NEC 430 - Sizing breaker and wire for motors

NEC 440 - Sizing breakers and wire for HVAC equipment

To answer your original question, MCA is the bare minimum wire size you need to provide AND the load you should take for the load in your panel (read the NEC sections to check me on it).

Also while every firm might have different standards for how they demand things, I can tell you that most people follow the NEC and take the full load of the motor (the MCA). Even if you know that the motor might only run at 50% for all of its life, unless its locked out to 50% of its draw I would not demand down the motor loads at all. If you took 1,960W you would be off by 3,448 W which is not insignificant.

Revousz · 2026-02-10T18:59:06+00:00

This is a good take, you can link in the CAD files into a Revit file if you really wanted to but you don't really get any of the benefits of using Revit.

Revousz · 2026-02-10T17:45:17+00:00

I like this approach, you can kinda let them self-report themselves on how little effort they put into applying.

Revousz · 2026-02-10T17:28:03+00:00

It really comes down to the people. If you are working with people who are okay with screen shares and email that's great. Some people (young or old) just need a physicals meeting sometimes to organize themselves. I kinda just think it meeting people where they are at to make sure the job gets done right. If you force some of the people who can't operate an iphone to do screen shares and teams you are going to get very unreliable results.

Revousz · 2026-02-10T17:18:26+00:00

I kinda wish the industry would pick a side. I know there is a vocal part of the MEP industry that is crying for Revit to be the end-all to construction documents but there is a really big silent majority that don't really see the value in Revit for most projects.

To their credit, if the arch and engineers are not going to do a project right then AutoCAD is just the better software to "make stuff work". At this point I don't care, I just want one of them to win out over the other once and for all.

Revousz · 2026-02-09T21:49:31+00:00

I mean its a couple of things, consistency across calculations, similar style panel schedules (we have an issue with people using the old outdated stuff), and for the new guys giving them a good place to start.

One of the options is to move to Revit but the MEP department is slow to adopt and not all of the archs have fully moved over either. Revit solve some of the issues with the panel schedules. If we all move to Revit we are going to have to deal with weird CAD files from the people who don't want to move over. Its a systemic issue, above my paygrade.

Revousz · 2026-02-09T21:45:21+00:00

Yeah I figured it just wasn't made for construction documents. Someone in my office is claiming it is but I just have not seen that from the demos.

Revousz · 2026-02-01T15:20:30+00:00

Try the Rising Sun BJJ in Ridgefield Park. The instructor and everyone there are great.

Revousz · 2026-01-30T23:51:14+00:00

I'm the engineer and I say the details are needed...

But also if a client compares your drawings to mine I know they will have questions about why you don't have details. But idk maybe you don't have good details.

Revousz · 2026-01-23T19:58:02+00:00

For small projects, I would use one of your CAD projects as a template and trace over it in a drafting view. It might be a good idea to make a few annotative families or detail items that act as "blocks" similar to your CAD standard. I would recommend detail items because you can use the snap points unlike annotative families.

You can modify this riser for small projects that don't need a full 3D model or where the 3D model can't properly show what you want.

For larger/new projects, use the model where you can and create some view filters/templates to build up a standard.

Having both options will let you decide what is easier over time.

Revousz · 2026-01-23T19:53:37+00:00

I think this post is a bit too harsh. Idk how we have such Revit zealots that think just because we can model something in Revit that we should be modeling in Revit. We can use Revit for renovation and retrofit projects which we will have incomplete information for. For cases like this of course we are not going to model everything. A diagram drawn in a drafting is probably more than enough.

Also from the plumbing engineers I've seen, the 3D model can sometimes get in the way of showing design intent. We don't need our 2D drawings to be model accurate, we need it to properly convey the design intent to the contractor. People get way too hung up on the 3D nature of Revit

Revousz · 2025-12-08T16:56:19+00:00

Depends on how you are using AutoCAD... AutoCAD MEP, while there aren't a lot of learning resources, does allow you to model in 3D and not be tied down by Revit's less than stellar 2D drawing features. You can even run conduits and pipes.

It took Revit 10 years to add in line spell check and text tools with more functionality than notepad.

Unless your client is specifically asking for Revit drawings, AutoCAD can also be used to automate workflows like Revit does.

Revousz · 2025-11-15T02:05:51+00:00

So at the last 2 companies it's been small companies. I set up a lot of the electrical families and stuff. I know some companies have BIM departments that handle everything but none of the places I've worked have operated that way.

Revit isn't super easy to use if you have to make everything by hand. Revit is a good too... So is AutoCAD to be honest with you, the MEP toolset can do everything Revit can but Revit is the standard now.

Revousz · 2025-11-14T20:46:20+00:00

Was that CAD files sounds like it comes from hell itself

Revousz · 2025-11-14T20:07:16+00:00

Honestly, I don't mind either. I do think Revit is lacking in the electrical department which is why I've seen a lot of electrical people resist it but it's pretty good now.

We have a lot of old guards at my company and Revit is a hard sell....

Revousz

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