Inverted Motors

[Darrell Henry]

What is the best way to incorporate inverted motors in truss? 

 

For example I have a PA deadhung from a truss and am using a motor for pull back inverted on the truss. 

 

I don't necessarily need it to calculate properly as I can manually manipulate with point loads to get that.  But I do need to not have a whole bunch of red highlighting. 

 

 

[SCParker]

Could you not just keep said motor disconnected from the truss?

[Darrell Henry]

No. They will remain in error state (red background black text) and even if you turn everything off and calculate them alone they will generate a not connected to a load error. 

[SCParker]

How about if you clear all calculations and then only calculate the gear selected?

Oh, wait. Are you speaking about the report itself? Or the hoist text on the drawing? My solutions apply to just the stuff on the drawing.

 

I'll do some testing if these ideas don't work for you.

 

Best, Scott

[Enoch Seutter]

There is a workaround to this that I have found.

- using the Hanging Tool, insert your motor icon, so on your drawing it looks correct.

- insert a point load onto your truss right where the motor is, with your motor weight, and the weight you have calculated that it would be picking up from your PA.

- reduce your PA total weight by the weight you have calculated your pullback motor to be supporting.

 

That will remove the error of motor has no load, and your weight is still calculated on the truss with braceworks.

 

Cheers,

Enoch

[Darrell Henry]

What are you referring to when you say hanging tool? 

 

Isn't braceworks still going to assume that the motor you are inserting is connected to the ceiling? 

 

So if you have 2 motors picking up a truss and add an invert that way, won't it divide the load across the 3 now? 

 

I may be missing something though as I am unsure as to how you are placing the motor.   

[Enoch Seutter]

Tool Sets > Hanging Position Tool

From the "Position Symbol" pull down, find the same symbol in your document that you are using for the motor in question. Place it in the same location as the motor in question. (And remove the actual motor)

 

Then using the Insert Load Tool, add the motor / pickup weight to the exact point where that motor would have been, this gives Braceworks the weight that would be applied to that spot on the truss.

 

Onto your Line Array weight, using the Insert Load Tool, add the weight of the line array to the contact point on the truss. (You will have to do the calculations yourself as to how much weight is on the line array point, and your pullback point.)

 

If you have used the Speaker Array Tool, make sure to turn off "Include in Calculations" on the bumper and speakers.

 

I use the hanging position tool because it easily duplicates the motor symbol in question. You could modify any symbol really and make it appear to be the same as the motor.

 

What this is doing is removing the actual motor, there is no longer a motor there. On your 2D plan, the Hanging Position Tool will have the icon there so you will still see that a motor exists there, in your 3D, you will see the motor, but the chain will be short. Braceworks will not think there is a motor there, but will still calculate the weight of that motor and PA.

 

Cheers,

Enoch

 

[Darrell Henry]

Got it -- I had done a similar thing and just converted the motor to a group to remove its BW functionality. 

 

Of course -- there should just be a function to attach a motor to a truss as an invert. 

[Enoch Seutter]

I know you can when hanging truss below truss, and invert motors all day long. I would love to see the ability to invert a motor off of truss with "X" amount of user defined weight and BW calculates based off that.

 

Cheers,

Enoch

[CETLV]

when you use the hoist tool, there is a choice of hanging the motor with hook up or down.  This option inverts your motor from step one.  Then this reverses all the data fields.  For instance the "hook height" becomes the hook on the hoist, and the "Load Trim" becomes the chain side hook.

[Darrell Henry]

That's not the issue. I need the hoist to attach to a piece of truss and then transfer its associated loads to the node as opposed to attaching (hoist up or down) to an imaginary roof. 

[CETLV]

Sorry I just cant make sense of that.  If you are attaching that motor to truss, thats where the load falls.  If the truss is supported by two points on each end, its a center point load on the truss.  Whether the motor is up or down should not make all that much of a difference in the numbers unless there is a ton of chain out...  Is the truss deadhung?