Re: Using an EQUATION variable as a Type input

[Jeff Thornton <thornton@xxxxxxxxxxxx>]

At 03:58 PM 5/26/2003 +0000, you wrote:

> Suppose I want to draw water from a solar system (Type 45) everyday at
> sunset. I created a set of equations to calculate the sunset time for each
> day of the year. This value changes every 24h. When I try to use it as an
> input for Type 45 the value for the first day is used all year long. I
> checked the list file where I found the following message:
>
> *** WARNING *** THE INITIAL VALUE OF TAP        WILL BE USED FOR VALUE  2
>
> TAP is the variable that defines the mass flow rate. TAP is zero until the
> sunset time is reached.
I'm guessing that you used the variable TAP as the initial value as well as 
the INPUT into your type.  Instead of:

INPUTS 2
2,1  TAP
20.  TAP

Use the following

INPUTS 2
2,1  TAP
20.  0.

Any variable that TRNSYS sees as an Initial value it assumes you want 
constant for the duration of the simulation...

Jeff



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