Hired-Hand Emergency Back-Up and Alarms: Secondary Sensing System Expansion - Manual (Page 20)

Manual No. 4801-3001 Rev 7-08 Secondary Sensing System Expansion 20 of 46
Important!
Before continuing, one must determine which type of system is installed for this specific application.
If the S
3 Expansion is connected to a Hired-Hand Evolution 3000 or Evolution 3001, refer to
Section 9.1 for a description of the Back-Up operation with the Evolution 3000/3001.
9.1 Operation with the Evolution 3000/3001
9.1.1 Normal S
3
Back-Up Operation
During Normal Operation, the S 3 Expansion always maintains the temperature between its high and low
limits. It accomplishes this by using its temperature sensors and its four stage outputs. If the temperature
drops below the Low Limit, the Heat stage will come on. That stage will not turn off until it warms the
building at least 2
°. The same is true if the temperature goes above the High Limit however, there are three
levels of cooling stages on the Back-Up System. The following example explains the operation of the
stages in relationship to the temperature and the limits. In this example the Low Limit is set as 66º F, and
the High Limit is set as 86º F. If the temperature drops to 66º F, then the HEAT stage turns on. The
HEAT stage turns off when the temperature rises to 68º F (2º above the Low Limit). If the temperature
rises to 86º F, then COOL 1
turns on. If the temperature
continues to rise to 87º F (1º
above the High Limit), then
COOL 2 turns on. If the
temperature rises to 89º F,
then COOL 3 turns on. When
used with EV-3000/3001,
Cool 3 comes ON and Cool 1
will go OFF to disable
sidewall/negative fans while
in tunnel ventilation. Stages
turn off at temperatures as
indicated by the arrows in
Graph 1.
Graph 1: Cool 1, 2, 3 and Heat
Temperature (°F)
Heat
Cool 3 - Tunnel
Cool 2
Cool 1 - Vents