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Page 53
Chapter 4: E2 Controller
Screen Lock Feature
You may lock any of the status display screens, bypassing the display screen
time-out function. This is sometimes useful for maintaining visibility to a specific
screen when testing, making adjustments, or troubleshooting the system.
Simultaneously press the program
key and Enter key for approximately
3 seconds to turn the screen lock feature On or Off. When a screen is locked, it
remains displayed unless you press the Up or Down arrow keys to select
a different screen within the menu loop. A symbol ( ) appears in the upper
right corner indicating the screen lock feature is On.
4.5.2.6 Temperature Sensors
The temperature screens display the supply air temperature as measured by
sensors located in the cold aisle side of the Cold Row cabinet. The sensors are
located within the cabinet in upper, middle, and lower zones as called out in
the display. Values measured by the sensors may be used to individually control
the speeds of the fans (see Section 4.4.4.1).
4.5.2.7 Static Pressure
The Static Pressure screen appears in place of the Upper Temperature Sensor
screen shown in 4.5.2.6 if your unit is configured for static pressure control
instead of zone temperature control. This screen displays the current operating
static pressure. The static pressure setpoint and the current proportional control
signal to the fans appear below. With static pressure control, all three fans
operate at the same speed and are controlled to maintain a constant static
pressure setpoint.
4.5.2.8 Water Temperature
Displays the temperature of the water entering the coil (EWT) and the
temperature of the water leaving the coil (LWT). The controller compares the
two values and signals a "NO FLOW" alarm condition if the difference
between the two values is less than 2°F (default value) during cooling
operation. A warning message, “Condensation possible,” appears if the
dewpoint of the air is equal to or higher than the EWT.
4.5.2.9 Setpoint Values
Displays the current operating Temperature and Humidity set points and control
method. If configured for Dewpoint control, the controller displays the
calculated dewpoint set points for dehumidification and humidification as
derived from the operating temperature and humidity set points.
NOTE: Display screens shown with a dashed border appear only if the
applicable feature is enabled.
Figure 4-21 (Continued), Information
menu loop.
(Continued on next page.)