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Active Member
Negaquark
Posts: 10
Registered: ‎04-22-2009
Message 1 of 4 (494 Views)

How to create a variable length LED Luminaire (lighting fixture)

494 Views, 3 Replies
09-12-2012 11:51 AM

 I was trying to make a variable length luminaire that could calculate the load automatically.

The problems I came across were dimensions & watts could not be calculated together, or the message

"Instance Parameters can't be used in Type Parameter formulas.

Type Parameter "Length" is driven by Instance Parameter(s): "Feet"."

 

First step is to determine the Load per foot. (15W as example)

Family parameter/Type

  • Name: Apparent Load
  • Discipline: Electrical
  • Type of Parameter: Wattage
  • Group parameter under: Electrical Loads
  • Value: 15VA

Next step is to determine the length. (4 foot typical length)

Family parameter/Instance

  • Name: Feet
  • Discipline: Common
  • Type of Parameter: Integer
  • Group parameter under: Dimensions
  • Value:4

Family parameter/Instance

  • Name: Length
  • Discipline: Common
  • Type of Parameter: Length
  • Group parameter under: Dimensions
  • Value: Feet * 304.8mm (or 1' for imperial)

Family parameter/Instance

  • Name: Calculated Load
  • Discipline: Electrical
  • Type of Parameter: Wattage
  • Group parameter under: Electrical Loads
  • Value: Feet * Apparent Load

Now for the Connector Element

Apparent Load should be Associated to Calculated Load

Label the Length Dimension

 

This works for a straight line LED luminaire.

 

For a circle with variable radius & perimeter try this:

Add

Family parameter/Instance

  • Name: Radius
  • Discipline: Common
  • Type of Parameter: length
  • Group parameter under: Dimensions
  • Value: 304.8mm

Family parameter/Instance

  • Name: Angle
  • Discipline: Common
  • Type of Parameter: Angle
  • Group parameter under: Dimensions
  • Value: 45

Replace

Family parameter/Instance

  • Name: Length
  • Discipline: Common
  • Type of Parameter: Length
  • Group parameter under: Dimensions
  • Value: Angle / 360° * 2 * 3.14 * Radius

Family parameter/Instance

  • Name: Calculated Load
  • Discipline: Electrical
  • Type of Parameter: Wattage
  • Group parameter under: Electrical Loads
  • Value: Length/1000mm * Apparent Load

 Label the Angle & Radius Dimension

 

*Expert Elite*
CADastrophe
Posts: 3,336
Registered: ‎08-28-2009
Message 2 of 4 (484 Views)

Re: How to create a variable length LED Luminaire (lighting fixture)

09-12-2012 12:47 PM in reply to: Negaquark

Negaquark wrote:

 I was trying to make a variable length luminaire that could calculate the load automatically.

The problems I came across were dimensions & watts could not be calculated together, or the message

"Instance Parameters can't be used in Type Parameter formulas.

Type Parameter "Length" is driven by Instance Parameter(s): "Feet"."

 

Next step is to determine the length. (4 foot typical length)

Family parameter/Instance

  • Name: Feet
  • Discipline: Common
  • Type of Parameter: Integer
  • Group parameter under: Dimensions
  • Value:4

Family parameter/Instance

  • Name: Length
  • Discipline: Common
  • Type of Parameter: Length
  • Group parameter under: Dimensions
  • Value: Feet * 304.8mm (or 1' for imperial)

That error would be occurring because  the parameter "Length", although intended to be an Instance Parameter, is defined as a Type Parameter in the Family.

Corey D.                                                                                                                  ADSK_Logo_EE_2013.png    AutoCAD 2014 User  Revit 2014 User
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*Expert Elite*
CADastrophe
Posts: 3,336
Registered: ‎08-28-2009
Message 3 of 4 (482 Views)

Re: How to create a variable length LED Luminaire (lighting fixture)

09-12-2012 12:55 PM in reply to: Negaquark

Negaquark wrote:

...The problems I came across were dimensions & watts could not be calculated together... 


You can create a formula to directly associate the load with actual length - You just have to make the length unitless:

 

Total Watts = Watts per Foot * ( Length / 1' - 0" )

 

Attached is a family basically demonstrates my method, in case it's of any help. (Revit 2012)

Corey D.                                                                                                                  ADSK_Logo_EE_2013.png    AutoCAD 2014 User  Revit 2014 User
──────────────────────────────────────────────────────────────────────
⁞|⁞ Please use Mark Solutions!.Accept as Solution and Give Kudos!Give Kudos as appropriate to further enhance these forums. Thank you!
Active Member
Negaquark
Posts: 10
Registered: ‎04-22-2009
Message 4 of 4 (476 Views)

Re: How to create a variable length LED Luminaire (lighting fixture)

09-12-2012 01:21 PM in reply to: CADastrophe

Those were just sample errors I came across while trying to create the luminaire.

This is a "How to thread", not a "Please help me" thread.

I remember reading a post with this type of problem, but could not find it again once I solved it.

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