I am trying to create a system for day trading only, and i want it to exit all trades before the market close. Is there a way to trigger a sell order based on time ?
I would really appreciate any help with this.

Try a search for "time based exits" over the "entire site" and you may find an answer to your question.

Thank you for your answer,   I actually already tried to look into the other topics before posting this new one. What I am looking for is a formula to make a sell at a given time before market close on intraday data. example : sell when indicator gives signal or time is 15:55.

Wabbit's post in the link below (refer Intraday section) provides a comprehensive answer to your question.

 

http://forum.equis.com/forums/post/29444.aspx