Here is an example Real Time Control (RTC) rule for the opening and closing of an orifice.
RULE Orifice1
IF SIMULATION CLOCKTIME >= 01:00:00
AND SIMULATION CLOCKTIME <= 2:00:00
THEN ORIFICE OR1@82309b-15009b SETTING = 1
ELSE ORIFICE OR1@82309b-15009b SETTING = 0
PRIORITY 1
; Opens up the orifice at hour 1 of the simulation
via Blogger http://www.swmm5.net/2013/07/real-time-control-rtc-rule-for-opening.html