Condec DLR3110 - Manual (Page 9)

Installation and Wiring 5
• TARE function key (6). The AUTO TARE (Auto.tr) feature is enabled in the Configuration mode under
the ZERO SET selection. When AUTO TARE is enabled, pressing the TARE key automatically tares out
the value of the current pressure display reading and shifts the display to the P (delta P) mode. The
resultant ZERO reference reading is useful in cases where it is desirable to subtract the atmospheric
pressure from an absolute reading to obtain a quick gauge reference.
NOTE: This pseudo-gage reading is only valid for the current atmospheric pressure that was tared out. Any
subsequent changes in atmospheric pressure result in an error.
• PRINT key (7) issues a demand serial printout of the display data from the indicator.
• UP (8) and DOWN (9) arrow keys step through and display the data in the conversion units that were
selected in the Configuration mode.
Figure 2-3. Display/Keyboard Functions
2.6 Freeze Mode
Freeze mode, used for testing pressure switches, is an edge triggered input signal that freezes the last display
update for the number of seconds (1 – 10 seconds) selected in the Configuration mode. The Freeze mode is
enabled in the CONFIG ?
menu under freeze time selections (Refer to Section 5.11 on page 21 for enabling the
Freeze mode).
Figure 2-4. Freeze Mode CPU Connections
Either opening or closing of a switch contact between an active input (I/O 1 or I/O 2) and RETURN “freezes” the
display (for the pre-selected amount of time in seconds) as shown above. However, while the display is in the
freeze condition, it does not respond to another contact transition
.
PSI
P Gage Abs
ZERO DISPLAY TARE PRINT
YES NO
CE ENTER
2
3
1
8 9 7 6 5 4
TB2
S4
OUT
S5
IN
RETURN
I/O 1
I/O 2
(DIGITAL COMMON)
PRESSURE SWITCH
JUMPER PLUG SHOWN ON S5 CONFIGURED AS AN INPUT
(+5 VDC)