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Maurizio,<br>
It looks from what you describe as though your best option would be
to write a new controller component. You cannot directly implement the
IF..THEN..ELSE structure using EQUATIONS in an input file.Often times
you can fake an IF..THEN..ELSE statement using one of the Boolean
functions as a multiplier on the variables that you wish to set. For
example, if your condition were:<br>
<br>
IF (T_supply_air < T_set_supply - dT_dec) THEN<br>
mode = -1<br>
mode_status = 0<br>
ELSE<br>
mode = 1<br>
mode_status = 0<br>
ENDIF<br>
<br>
then you could get the same effect by putting the following in your
input file:<br>
<br>
EQUATIONS 3<br>
ModeCheck = LT(T_supply_air,(T_set_supply - dT_dec)) !ModeCheck has a
value of 1 when T_supply_air is less than T_set_supply-dT_dec and 0
otherwise<br>
mode = -1*ModeCheck + 1*(ModeCheck-1)<br>
mode_status = 0<br>
<br>
however, the control scheme that you describe below is too complex for
such tricks I think. The other alternative is that you might be able to
implement your control strategy in Type40.<br>
<br>
<blockquote cite="mid014b01c5766b$d1f1a520$a313a393@sorce" type="cite">
<div>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="font-size: 10pt; font-family: Arial;">In addition, does exist a
manual for the equation tool?</span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span
style="font-size: 10pt; font-family: Arial;"></span></p>
</div>
</blockquote>
The Simulation Studio equation tool is described in section 2.7
of the Simulation Studio manual (volume 2 of the TRNSYS 16
documentation set). There is additional information about the functions
that can be implemented in equations in section 7.6.8 of the 07-TRNEdit
manual.<br>
<br>
Kind regards,<br>
David
<pre class="moz-signature" cols="72">--
David BRADLEY
TRNSYS Engineer
Solar Energy Laboratory - University of Wisconsin, Madison
1500 Engineering Drive
Madison, WI 53706
United States
ph: +1 608 263 1589
fax: +1 608 262 8464
email: <a class="moz-txt-link-abbreviated" href="mailto:dbradley@engr.wisc.edu">dbradley@engr.wisc.edu</a></pre>
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