Building Electrical Power Distribution Systems with Transformers and Panel Boards in Revit

Now that we've placed our analytical areas, we will create a power distribution system to power up each area. So what do we mean by power distribution system? I've created a separate diagram here. Let's take a look at it.

So what we have is a power source, and maybe it's from a utility company or a solar array or even a generator. It's a main power source providing power to our building. Once that power gets to our building, our site, we might have an outdoor transformer.

Revit calls these wet transformers because they're outside. From there, we might bring that power into a main distribution board. This board will let us divide the power up wherever it goes into the building.

For example, it might go towards panel boards. These are boards with circuits that will power our switches, receptacles, and lighting. We might power directly into our equipment, for example, HVAC equipment on the roof.

Or we might power to another transformer. Transformers inside the building are considered dry transformers per Revit, and that might be used to power something like an elevator motor. So isn't this cool? It's the power that supplies every electrical device in our building.

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So let's go ahead and set this up in our Revit model. So here in our project, we can see our analytical areas all in blue. And that's because I'm in the electrical floor plans, electrical analysis level one.

Now, almost all of our work will be in our system browser. So let's go ahead and get that opened up. We're going to go to View tab, User Interface, and then check the box for System Browser.

It might open up really small like this, and what we're going to do is expand it out so we can see it clearly, and so that we have all of the tools on the right available to use. Now, mine is set to the Systems Browser. I want to change that now to the Electrical Analytical Systems, which is the last option on this list.

Now, I'll notice a couple of things. Number one, I have an unconnected folder, and this contains all of my areas. If I move my floor plan over to see it more clearly, I can click on the various areas, and they will highlight in the plan.

Let's close that for now. We'll click the minus, and we also notice we have a utility here, and it has a few warnings because it's not connected. It's already here.

We're going to delete this so we can start fresh. So, I'm going to select Panel Board 4, hold Shift on my keyboard, and select Panel Board 1. Now, I can right-click and delete those panel boards. I can also right-click on the main switch board and click Delete, and right-click on the utility and also click Delete.

So, now we can start fresh. All of the buttons we need are on the far right of the System Browser. The one we're looking for right now is called Add Electrical Analytical Power Source.

I will click that. It's quite a mouthful of a name, so I can click here and look at its properties. Here is the name I can select, and we'll just call it Utility for now.

And let's take a look at its properties. If we scroll down further, we see it has a distribution system. Right now, it's set to None, so we can't connect anything to it.

We're going to drop this down, and let's select 480 volt. So, it's a 480 volt system bringing power to our building. So, once that name change goes into effect, we'll see it right here.

And from here, we want to transform that power into something more usable. So, let's click on Absolutely Nothing, just out here in the System Browser. And we want to go to our Add Electrical Analytical Transformer tool.

So, we'll click that. And it just opened up our unconnected folder, because as of right now, it's not connected to anything. It's just up here, unconnected.

So, we need to click on it. It turns blue in our System Browser, and then we can take a look at our properties. First off, we'll give it a name.

And we can just call this Transformer, Transformer 1, or even just Wet Transformer. Now, we have a distribution system. This is the incoming distribution system.

What's feeding this transformer? Right now, it's set to None, but let's make it 480 volt, so that we can connect it to the utility. And let's scroll down a little further. The secondary distribution, that is the output voltage.

And we'll change that, and we'll drop this down to the 120208Y. Now, the Supply From is set to None. Now, this is kind of a glitch that exists in Revit, and it won't let me pick anything, even though I've set a distribution system.

What I found I have to do is click in the browser out here, and then click back on that transformer, and now I can supply from the utility. And so, that should work. As long as our distribution system is set to 480 volt, we should be able to supply from the utility.

And watch it make that change. Now, we've got the transformer being supplied from the utility. So, if we remember from this diagram, after the transformer, we have a main distribution board.

So, let's set that up now. I've clicked on Nothing in the browser, and this will be called, for Revit's purposes, an Analytical Bus. So, I want the Analytical Bus tool.

And again, it comes in unconnected to anything. That's okay, let's give it a name. We could call this Main Switchboard, would be a pretty simple name, or even Main Distribution Panel, or Board.

Feel free to use the name that makes the most sense to you. Now, we need to connect it to power. Distribution system, we need to set that first.

Well, where are we at now? We're no longer at 480 volt, we're at the 122.8Y. And our supply from, let's drop that down, we can now supply it from the wet transformer. So, we've got our utility, our wet transformer, our main distribution board, our main switchboard, and now we can connect everything to that main distribution board. Let's start by adding some panel boards.

And what I mean by that are those circuit panel boards. So, we call those, in Revit, a bus, again. So, Analytical Bus.

And because I had the main distribution board selected already, it just put it in right below it. If I didn't have that selected, let's see what would happen. I'm gonna undo, and if I have nothing selected and add the bus, it goes right back to unconnected.

And so, we'll need to connect that up. In order to do that, we have to set our distribution system to match, which is the 120.208, and now we can supply from, sometimes we get that glitch, click away, click back. Now we can supply from our main distribution board.

All right, and it has this long mouthful of a name, and we wanna give it a clean name. We'll call it PB1, for Panel Board One. And now I've got an actual panel board connected to my distribution.

Now, I wanna go back to the distribution, and it's currently set to 20 amps. Let's give it 1,500 amps, and we'll give our PB1, it's set to 20 amps, we'll make that 200 amps. And with that, we've already got one set up, so it's easy to replicate this and have all four of our panel boards.

So I'm going to right-click and say Copy to the Main Distribution Board. And it says PB1. I can click right here on PB1 and give it a dash two.

So I've got PB2, and I'll right-click and I'll copy that to the Main Distribution Board as well, and repeat the process. Rename this PB3, and I'll right-click again, Copy to, and our Main Distribution Board, and this one will be PB4. And because we're creating copies, it has all the same properties, 200 amps, 120, 208 Y. And so we're all set up with our panel boards.

Now we can take our unconnected areas and apply them to panel boards. We don't need to be perfect about this. If you get one different from mine, that's okay.

We want to apply them to the panel boards. And so we'll start with Classroom 1. Where do we want this to go? We want it to go to Panel Board 1. If I click it, I have a couple of ways to do this. Number one, up here in the Modify Electrical Analytical Loads, I can say Supply From, drop that down, and it can go to PB1.

Let's do Classroom Area 2, and look at the other way to do this. If I go to the Properties, I also find a Supply From, and I can change it here. Either way, it's okay.

It's gonna put it into PB1. So I'm gonna do this for all of my remaining classrooms. I'm gonna put those on to PB1.

All of my remaining Level 1 classrooms, PB1. My Level 1 Corridor, also set that to PB1. And I want all of my Level 2 classrooms to go to PB2.

So let's get that taken care of. Level 2 classrooms on to PB2. Pretty quickly, we're starting to organize our panels.

And we'll take a quick pause here to notice that the panel boards are now starting to load up with power. I can expand this out even further to see everything going on. Quite a bit of information here in the System Browser.

Go a little further. There we go. So all of this load is starting to come, for example, to PB2.

We're starting to get some apparent power. And that power is then being combined to our main distribution board, wet transformer, and utility. So Revit does that, adding automatically for us.

Let's keep going. I want the L1 library. We'll put that on to PB1.

The L1 restroom can go to PB1. The L2 corridor can go to PB2. L2 restrooms can also go to PB2.

And our Classroom 3 can go to PB1. We're left with the cafeteria, the gym, and the kitchen. Well, the cafeteria and the gym, they could go to PB3.

And the kitchen, that's a huge load. It might want to go into its own panel board. We'll do PB4 for now.

And let's take a moment to look at this. We can see the PB4 has a huge load on it. Yet the PB3, not as much.

PB2, and then PB1. We could then, as our electrical engineering continues on in the building, we might want to redistribute these loads. And Revit, by telling us what the connected power is, helps us do that.

We can try to balance our loads. We might even need to split things up. Perhaps the kitchen needs to have a couple of panel boards, not just one.

So those are the decisions that Revit can help us make as we set up this analytical model. But for now, we'll just keep going on and adding to our distribution system. We'll click back on Main Distribution Board.

And we might want to take a look at our PDF. The BIM 323 Analytical Areas PDF that's in our Download folder and the PDFs folder from there. And we have some analytical equipment loads.

So our HVAC unit, and it lets us know we're at 20,000 and our elevator at 15,000. So 15 kVA and 20 kVA for those units. So let's add those.

Now let's start with the HVAC equipment. I want to click on Main Distribution Board. It'll be blue and highlighted because that way it will go directly to this board.

And up in the top right, I have a Add Equipment Load. So I will click that button. And Revit just calls it Equipment Load for now.

We're gonna call this HVAC. And we might just call it 1 for now. So HVAC 1. And we see it has a different symbol.

It's an Equipment Load. And over on the left, it's supplied from the Main Distribution Board. And we can add some information here.

So first off, the apparent power, we want this to be 15 kVA. We'll type in 15,000 and hit ENTER. So that's how much power it needs.

And let's go up to see what other options we have. It's 208 volt, three phase, Main Distribution Board. I think we're all set with that.

So there it is, our HVAC 1. Now we can right click. And we can duplicate this one by saying Copy to Main Distribution Board. It's gonna call it HVAC 1. We'll give it a dash 2. Perfect.

Now we've got two pieces of HVAC equipment attached to our Main Distribution Board. Now we also want an elevator. So I'm gonna go back to my Main Distribution Board.

And I wanna click on Nothing this time because the elevator is special. The Main Distribution Board is 120208 volt here. And so the elevator will be different.

So let's click out into space in our system browser and we'll add another equipment load. And it's gonna be called Unconnected Equipment Load. Let's rename this and we can call it Elevator or Elevator Motor.

And we want to set this up. It's 480 volts and that's correct. We'll leave it 480 volts, three phase power.

But our parent power will be 20 kVA. We'll type in 20,000 and we'll scroll down and we'll do Supply From. Right now it only can supply from the utility.

We could connect it to that, but that would literally mean kind of running a line from the utility, the power company, right to our elevator motor, bypassing our distribution system. We don't wanna do that. But why won't it let us connect to our distribution? Well, that's because our distribution is set at 208 volt and this electric motor is 480 volt.

So those two are not compatible. We'll have to add another transformer. So let's go ahead and click on Nothing again.

And I want to add here a transformer, Add Electrical Analytical Transformer. And right now it's set to Nothing. So let's go ahead and adjust its properties.

The distribution system. This is the incoming distribution system and we'll call it the 208Y. So it's 208 volt coming in, but this will be a step up transformer and it can step up to our 480 volts.

And let's give it a name. We'll call this dry transformer because it's inside or we could call it a step up transformer or just transformer. Okay, and we wanna supply it from our main distribution board.

Well, there's that little Revit glitch. It's not letting us do it. So I'll click off of it, click it again.

And now I can do supply from main distribution board. And we'll watch it move down here. There's a dry transformer now on the main distribution board.

Now let's find our elevator motor and see if we can now bring it where it wants to be. Instead of supply from utility, we're going to supply from our dry transformer because that now works. Now they're both, you know, this one's coming in at 408 volt, our transformer, and then bringing us to 480 and the electrical motor is, or elevator motor is at 480.

We're all set. So awesome job. We now have our system browser with all of our analytical distribution systems set up.