Families with Nested Families and MEP Connectors

While trading some emails with Aaron Maller recently he mentioned that he observed that he could create circuits for nested shared electrical families. I don't recall Autodesk publicly taking credit for adding or allowing this behavior but I find that it has been possible as far back as the 2012 release. I'd try earlier releases too but I don't have them installed anymore. Since I started preparing this post I've discussed it with Jose Fandos and he confirmed that it is possible in 2011 too.

I'm a bit frustrated because I thought I tried to explore this possibility a couple years ago while making some electrical content. Rather than dwell on what I thought wasn't possible I'll focus on what IS possible instead.

Experience tells us there are many components that have a variety of options or configurations that can prove difficult to include connectors in, for example a boiler with its electrical panel available either on the right side OR the left side. When a single connector is placed we are inclined to placing it in the "middle" so we can "connect" it to a power supply. That's easier to accept for electrical connections but not as easy for piping or duct.

When the connectors are native, placed directly in a family, it isn't possible to put two connectors in place but disable one or the other. Revit sees both even if we only use one of them in the project. With two connectors in the model we can define where connections take place more accurately but ultimately we end up with one valid connector (connected) and another lurking as "unassigned" within the system browser. It might not a big deal but Revit's developers encourage to assign everything to systems so this approach means there will always be some we can't assign properly.

If the connector is part of a nested shared family and this nested family is assigned a Yes/No parameter to control its Visible parameter we gain control over not only when it is visible but also whether or not Revit sees a valid connector in the host family when it is loaded into a project. This is a crude example with connectors for pipe, electrical and data circuits, offering a conceptual right and left configuration.

When I use a yes/no parameter to control the visibility of the nested families it is interesting to find that the system browser responds to their condition. As can be expected Revit will delete a circuit or system associated with a nested connector if we choose to turn it off.

So far I find that I can create systems, connect pipe and duct, draw wires as well as tag the nested shared families. This means that it may be a bit easier now to define a component that has multiple circuits. This can help counter the limitation that a family can only report circuit information (in a tag) for the primary connector when multiple connectors are in a family.

It isn't perfect...naturally.

Nested families with connectors are harder to see and therefore are harder work with. The connectors are only visible when you hover over the location where they are when you are using the appropriate tool, like duct, pipe or wire. That also means we can't use the convenient right click "create pipe/duct/wire" options because we can't see the connectors.

It may also confront us with a need for sub-categories for connector geometry, not for the connectors themselves but any forms we use to host them. It can be easier to find the connectors if we can see the hosting forms but we may not want to see them in every kind of view.

Ultimately I think it's worth exploring further. Perhaps you'll agree?

Conduit Connector Gone Rogue

I created a conduit connector "disc" that let's me attach conduit to any surface. I place the connector and then add conduit, easy. It's based on the other connector families that Revit provides in the library, these:

When I loaded the connector into a project and select it I find a bizarre value offered. I get the same value no matter what size I enter. This image is after trying 3/4", 1", 1.5" and finally 2".

I tried creating the parameter as a Common/Length as well as Electrical/Conduit Size. Doesn't matter...same bizarre result. The connector's size changes when I change the parameter in the Family Types dialog so it works. You can't enter value on screen. Fwiw, it happens to pipe connectors too. I added a pipe connector to a transformer (I know it's probably a bad idea to put water in a transformer, unless it is water cooled?)

Weird, just weird...looks like a bug that needs some squashing!!

Revit 2014 - Connector by Radius or Diameter

Prior to Revit 2014 we could only create dimensions for the radius of arc and circles and connectors. With 2013's release they added a diameter dimension tool which makes it easier to constrain geometry in the family editor. Round connectors also only could be defined as a radius before. Now in 2014 this subtle parameter gives us the option to choose which makes more sense, radius or diameter.

Love the subtle stuff!

Pick New Host for Connectors

I find myself wishing that I could pick a new host for a connector every now and then. It's a bit of a drag when I redesign something (or make a mistake) and have to recreate connectors all over again just because there isn't an equivalent process to define a new host like for other hosted elements. For the programming team it's probably not a particularly hard thing to accomplish, so it's just another subtle thing to add to the list of desirable Revit refinements.

Hide Those Connectors

A recent question at Revitforum.org asked about hiding the connectors in family content for the sake of cleaner previews.

To accomplish this:

• In the view you want to use as the preview
• Select the connectors
• Click Temporary Hide/Isolate
• Choose Hide Element
• Save the file
• Close the file

Dept. of Subtle - Connectors and Diameter

Sorry about missing a post on Monday, just ran out of day and evening too quickly.

If you haven't created a Revit Family using connectors then this might not be interesting, till later. If you have then you're probably already nodding your head and thinking, "I know where this is going".

Revit Connectors for pipe (round duct too) offer us the ability to map their dimensions to a parameter so the user can adjust them easily in the project environment. It also allows Revit to resize pipe that is connected to a connector. Hmmm, I think I'm going to be using that word (connector) a lot.

Pipe sizes (duct too) are usually thought of using inches, such as 1-1/2" or 4" diameter. Those of you that work in the metric system are shaking your heads now. They told me back in fifth grade that we are going to change to the metric system. That was more than a couple years ago unfortunately.

Ironically we can't just create a radial dimension for diameter. It is technically possible to control the size of a circle with a aligned dimension (and Reference Planes etc.) for diameter but it isn't as obvious as the radial dimension tool. You'll find a lot of content therefore has a user parameter for diameter and then a calculated parameter for half the diameter to drive the radius of the host surface and its related connector size.

Another consideration is the unit that a user enters. It is quite handy to create a parameter using the sneaky little Associate Family Parameter button found in the Family Types dialog. If we use it we don't get a say in which kind of parameter is created, it defaults to Common (discipline) and Length (data type). If you want to let the user enter inches then you need to make the parameter in advance so you can choose the parameter from the list offered in the Associate Family Parameter dialog instead. When you make the parameter in advance you get to choose Piping (discipline) and Pipe Size (data type). This is a separate Project Unit that can be configured for inches, it is configured this way as a default setting in the Imperial templates.

Same thing happens if you use the Options Bar Label: Add Parameter approach. The only reliable way to get the discipline/datatype you really want is to make the parameter in advance. It would be quite nice if we could create a radial parameter for diameter an use it to manage connectors directly without the little "half-the-diameter" dance. Here's a Video to Watch.

Dept. of Subtle - Revit MEP - Connectors and Height

It is important to orient connectors correctly. The "height" value or "radius" value for round connectors need to be "vertical". Here's an example of wrong (straight out of the family tutorials provided with RME).

Here's an example of correct:

MEP Rough-In Families - Follow On Post

I received the following in a comment to an earlier post
.
The image above that I believe prompted these questions.

I'm trying to decipher the picture and I have a few questions

1) How did you connect the piping to the P-Trap?
2) How did you connect the toilet flange to the toilet?
3) how did you connect the Double-Y w/8th Bend to a vertical pipe?
4) Did you end the hot and cold water supply at a valve for each of the components?
5) Are you using Revit to calculate flow requirements or pipe sizes?
6) Is this process easier or faster than placing a new fixture?
7) How do you create a system with this method?
8) How did you make the rough-in connector.
9) How did you connect it to the fixtures?

I am just beginning to learn Revit and am not using it to it's full potential yet. So far, I'm still just drafting in 3D. I'm looking for anything that will help to speed up the learning curve. Sorry this is so long winded. Thanks for the help.

To start with the answer, this concept is derived from the fact that RME cannot connect to a family in a linked file. If an architect places a toilet in their file the RME engineering must place their own toilet to connect piping. This is an alternative to placing a toilet, instead placing the rough-in fittings where the toilet would require them to be. They still must be coordinated but the rough-in fitting, in my mind, is consistent with the work on-site.

Answers:

1) The piping and p-trap is part of the connector family itself.

2) The toilet is not connected to the toilet flange. They occupy the same location. The toilet flange has the data that RME needs to allow for connection and to create a system.

3) The tutorials that come with RME show how to do that.

4) Yes, the pipes stop at the hot and cold water valves at both the sink and toilet.

5) I am not doing pipe sizing, I am a consultant who does training so I don't "need" to. Engineers are telling me that the sizing is a bit too basic at this time to really rely on. This was a mock-up of an idea that I've pitched to several clients who objected to placing toilets and sinks themselves.

6) Not faster necessarily but, in my view, more consistent with on-site process.

7) A system is connected to the rough-in connector family, the data needed is defined in the family. The fixtures are in the separate file so they are inert, "dumb".

8) In the family editor. RME ships with several connector families to use for this approach, simpler than mine but you can extend the idea to your own needs. You can download my examples; Sink Connector and Water Closet.

9) The rough-in family does not "connect" to the fixtures, it sits next to, above, coordinated with them.

I hope these answers help you on your way!!

Steve

RME - Connectors and their "Arrow"

This is referring to the arrow that appears on a duct or pipe connector icon in the family editor. This arrow indicates where the pipe or duct is...it must point toward the connecting pipe or duct. You can flip this easily when you place a connector on a face but not as easily when using the work plane option.
Connectors placed on a "work plane" define their "arrow" orientation based on the "positive" side of the Reference Plane used. The positive side of a Reference Plane is the left side of the "head", where the name appears (when you assign a name parameter to the ref plane). This is true for Reference Planes we add to a family. The stock reference planes that you find in the template behave the opposite way, go figure...positive is to the right side of the "head".

I suppose the connection arrow is just there to tease you in this instance. When the connector is applied to a "face" the "flip" arrow works. Remember the connection arrow represents the duct/pipe...it should point toward the connecting duct/pipe. Actual Flow direction is defined inside the properties dialog of the connector.

Oh...if the arrow is "wrong"...flip the reference plane, drag the end control grip at one end over the other, don't mirror because Revit will want to delete the connector.

Another worthy tip, brought to us by AUGI member Truevis aka Eric, is to use the "Split Face" tool on a face to define a portion of the surface to contain a connector as opposed to adding another solid to do so which you'll find in many of the stock families. May you "connect" well!

Duct Size Parameter - Inches - Revit MEP

If you used AutoCAD before using Revit you likely went through a bit of withdrawal from using inches as a base drawing unit. With Revit you had to get used to typing 0 space 6 for 0'-6" or 0 dash 6. Well in Revit MEP there is one instance at least where you get to enter relevant values when working through your design.

First if you are interested I posted a little video overview of this subject. Otherwise read on...

I am referring to the duct size parameters as the title suggests. In the Family Editor > Family Types dialog we can choose to Add Parameters to our family. Aside from providing a clever name we also can choose the Discipline > HVAC which in turn offers quite a few choices for "Type of Parameter".


When you choose Type of Parameter: Duct Size, Revit will require you to enter values in inches, which is easier since most duct sizes are referred to by their size in inches.

There's a catch though if you like to add parameters by using the Associate Family Parameter "sneaky button" in the properties of elements in the Family Editor.


This route precludes the use of the HVAC Discipline, Type of Parameter choices as it defaults to common and its subset of Types of Parameters. Not FAIR I say! I'm sure it is just an oversight!

To use it you need to start with Family Types > then Add Parameter. Then you can Associate the family parameter with the Element's parameter.

Revit MEP - Family Connector - Arrow Direction

When you create a Revit MEP family that requires a connector (most will) you need to pay attention to the direction of the arrow that appears on the connector. In the following image the arrow points down, out of a water closet fitting.

Yes the arrow is also different than the Flow Direction parameter in the properties of the connector.


If it were to point up then Revit would think that a pipe should connect from within the bowl of the water closet (toilet)...which would be wrong. You'd also likely get a message like this one.

This is trying to tell you that Revit just couldn't figure out how to get your fixture connected to the pipe you selected. Usually this message is related to the elevation of the pipe and the fixture or they are too close together for specified fittings to actually connect properly. When it comes to the pictured connector it means that the pipe is running the opposite direction AND that the elevation I used for the related pipe is too close to the same elevation.

Yes, you'll have to put on your detective hat, light your pipe and seek out the "elementary" explanation my "Dear Watson".

If you are curious the water closet fitting pictured above is part of a "rough-in" connector for a floor mounted toilet. The issue at present is that the basic plumbing fixtures that the architect uses in Revit Architecture has no connectors and that even if it did when their model is linked into RMEP they wouldn't be usable to connect pipe. Thus the notion of just the rough-in components instead of putting another toilet in the same place.

Turns out what we thought was "clever" is what Autodesk's RMEP team was thinking too and you'll find some basic connector families in the content with the release of Revit MEP 2009. Here's a screen capture of the mockup example.