eQUEST contains a large number of schedule types that serve different purposes. Regardless of the schedule types, all schedules are divided into three schedule categories: daily, weekly, and annual. To access a schedule, select any module and scroll towards the bottom of the component tree.
As with all things in eQUEST, when constructing schedules it is important to start at with the lowest level, in this case with daily schedules. Here, the 24 hours of the day are given corresponding values for a particular day type.
A weekly schedule consists of selecting daily schedules for the seven days of the week, holidays, heating design and cooling design days. It is critical to define the design days with appropriate values, as these days represent the heating and cooling extremes. For instance, when modeling internal loads, it is a good idea to define a heating design daytype with zero loads, and cooling design day with maximum loads, which is often done by using the weekday schedule for cooling design.
Finally, annual schedules consist of weekly schedules or of just one weekly schedule. Using multiple weekly schedules, multiple seasons may be constructed. It is important to define all weekly schedules chronologically starting with month 1, day 1 and ending with month 12, day 31.
Annual Schedules also have one additional parameter: photocell ctrl. Basically, this is an on/off override, where the sun is the control point. This is a useful feature, for example, when modeling parking lot lights.
Understanding the relationships of schedule categories, it is important to distinguish the different types of schedules. While eQUEST has 12 different types of schedules, we are only going to discuss the 3 most common schedule types: Fraction, Temperature, and on/off
The individual schedule types and their corresponding variables are edited under daily schedules. Weekly, and annual schedules simply organize the order of the day types. This is further illustrated as we look at different schedule types, starting with a fraction schedule
A fraction schedule is used for items like lights, and internal loads. In such a schedule, each hour has a fractional value of the design conditions. The fractional value is multiplied by the design value. When defining fraction schedules, it is common to specify three different day types, Weekday, weekend, and Heating Design day. This is necessary because the heat from internal loads should not be applied when sizing heating equipment.
A temperature schedule is used for zones, but is not a required input for zones. Temperature schedules define the setpoint for all 24 hours. Typically, it is necessary to have 2 annual schedules and 2 weekly schedules (1 heating, 1 cooling). However, it is typically necessary to have 4 daily temperature schedules (heating and cooling with occupied and unoccupied each).
Finally, On/off schedules allow a 0 (off) or a 1 (on) any hours of a day. These schedules are used for equipment such as fans or air-conditioning units. The wizards typically create weekday and weekend values for on/off schedules. Please keep in mind that a value of 1 simply allows an item to operate and does not mean that the item is 100% on. For instance, if a VAV fan is scheduled as on, it does not mean that the fan will operate at 100% power. However, if an item is scheduled as zero, it will consume zero power unless of course, there is a schedule override elsewhere in the program.