This video starts in full TRACE 700 mode (by going to options --> operating mode ---> TRACE 700). It introduces the additional variable required when doing an energy model as well as a load design model. Some of these variables: driftpoints, fan types, energy meters and more!
Now that we have established the calculation differences between Design and Analysis, let's take a look at the program. We are currently in Load Design mode but we can go to Options, Operating Mode, and select TRACE 700 700. This launches the full mode of TRACE 700. The Project Information has no change. Again, whatever we enter into the description field is displayed under Alternative 1. Select Weather Information also shows no changes.
Creating Templates and Rooms
0:42
In Create Templates and Create Rooms, there are very few differences. One small difference is that the field for Energy Meter is enabled in the Internal Loads Template. The most notable difference is in the Thermostat Template. The Thermostat driftpoints and Cooling and Heating Schedules are now enabled. A Thermostat Schedule can be used for scheduling set points at different hours in the day. However, if a room only has two modes, Occupied and Unoccupied, it is likely that a thermostat schedule can be replaced by entering driftpoints. When a driftpoint is entered the room will be allowed to drift from the set point to the driftpoint when the people schedule drops to 5%. When the people schedule is above 5%, the room is then conditioned to the room setpoint. The sensor locations are also enabled but are typically left unaltered, and they will not be addressed in this lesson.
Another field that is enabled is the Room Type, defined under the Construction Template as well as the Rooms tab of Create Rooms. There are only two options, Conditioned and Unconditioned. You will only need to enter this field when you wish to add an Unconditioned Room-- that is, a room whose lighting and miscellaneous load energy is taken into account. But not a room that does not affect air conditioning and heating energy. There are no further changes in Templates or in Create Rooms, which takes us to Create Systems.
Creating Systems
2:35
Remember, when creating a system, always give the system an appropriate name. This will be very helpful when assigning rooms to systems and even more helpful when assigning systems to plants. There are several additions to Create Systems when in Energy Mode.
The Fans Tab
3:01
The most notable change is in the Fans tab. In Energy Mode a fan can be selected and it can also be scheduled. However, the fan schedule modified only in rare cases. Fan selection, on the other hand, is very common. Upon selecting a fan, a default fan rate is selected as well as the Full Load Energy Rate Units. These values can be overwritten. The fan itself has an unloading curve associated with it so it is important to select the proper fan. Because this is a VAV system we want to be sure to select a VAV Fan. Once we select a fan, again, the Energy Rates are set to their defaults. While the fan automatically propagates the fields for the full load energy rate, the details of the fan itself are not visible on this screen. Each fan has an unloading curve associated with it, so it is important so select the proper fan. We will discuss unloading curves in a later lesson.
The last crucial change to the Fans tab is the Fan cycling schedule. Fans can be set to cycle with a number of parameters. Typically the fan cycling is set to cycle with occupancy. This works much like temperature driftpoints. The fans will operate continuously while the building is occupied. As soon as the system drops to 5% occupancy, the fans turn off and only turn back on to maintain the room driftpoints. Continuous fan operation resumes when the room is occupied again