I have a doubt regarding ASHRAE 90.1-2010 section 188.8.131.52a – “Space Control: The controlled lighting shall have at least one control step between 30% and 70% of full lighting power in addition to all off”.
So, should the manual control device have dimming control to meet requirement of additional control step between 30% to 70%.
Or alternatively, can the light fixtures in the space can be wired to control by 2 switches with only on/off control. Please clarify if this option meets the requirement of ASHRAE section 184.108.40.206a.
Thanks in Advance.