


In my last article we
discussed Revit Families and how to create and change them
to suit your needs. Family content is the backbone of a
project, and provides the information that can be extracted
from all parties involved to make BIM work to its fullest
potential.
Today we will take a look at Autodesk
Revit MEP content and focus on connections. Connections are
the means to which pipe, wire and duct can connect to a
family and make it a part of a system. Think of connection
as separate components inside of families. They contain the
information that determines what the characteristics of the
family will have. For example if families of a washing
machine and dryer were made with wiring connections, it
would be important to make sure that the voltage parameter
of the washing machine wiring connection had a value of
120V. It would be equally as important to make sure the
dryer connection voltage parameter had a value of 220V.
Connections are also similar to objects in how they are
placed. They require a face of a mass, or a work plane to
attach to. They often times need to be constrained to move
with the attached objects or planes when the shape of the
family is changed.
Shown below is a heat pump
family. It has a wiring connection and two pipe connectors
to accommodate water lines coming in and out of the heat
pump.
Since the voltage parameter can be set in the wiring
connection, the pipe diameter you would like to connect
to the pipe connection can be changed as well. We will
select the pipe connection and look at its instance
properties.

We notice that the connection has parameter
ready to be populated. It is important to remember that
at any time we can add shared parameters or create them.
This connection has the radius parameter and value
shaded back. When we click on the button to the right of
the value with the = sign, we get the parameter dialogue
box.
The radius parameter is set to equal the value of
another parameter that works from a formula. In this
case it gets its value from the Inlet Radius Parameter.
To see what parameters are at play inside of this family
we need to close these boxes and open the 'Types'
parameter dialogue box. If we want to disconnect the
radius parameter from the Inlet Radius parameter we
could choose
On the create
tab of the ribbon, let's go to the Family Properties
panel and click on Types.
Now we can see that this family has formulas set for
parameters according to how many tons the heat pump unit
is. This particular family type is for a 5-ton unit.
Boolean formula can be applied in the formula column to
get parameters to arrive at the value that you choose.
Once the values are correct we can look at what the
connector is attached to.
We can see that the three connectors are attached to
a work plane that has the mass also attached constrained
by a parameter. This assures that when the depth
parameter is changed the connectors move with the work
plane.
Integrating connections into your
families will assure that pipe duct and wire can be
connected and that your family content is included in
your systems.
This page last edited on Monday, February 14, 2011