Macurco CX-6, User Instructions

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Macurco CX-xx Manual (Rev-1.0) Eng
REV – 1.0 [34-2900-0512-0 ] 22 | P a g e
Calibration Due is resolved only with a successful field calibration.
NOTE: If a Fan or Alarm Relay is activated during Calibration Due, ‘Fan’ or ‘ALr’ will be appended at the end of the
display sequence.
4.4 4-20mA Loop
In High Mode “HigH”, the output will correspond to the higher output of the two sensors. For example, a CO reading
of 50ppm corresponds to an output of 8mA and a NO
2
reading of 10ppm corresponds to an output of 12mA. The
output in High Mode will be 12mA.
NOTE
: High Mode should only be used when the detector is used as a standalone unit. Dual Mode
must
be used
when the detector is connected to a Macurco DVP control panel.
In Dual Mode “dUAL”, the current fluctuates between different values when measured using an ammeter. It will
represent the CO and NO
2
readings simultaneously by using a signal that is readable by a Macurco DVP panel.
Clean Air – With the 4-20 mA function turned “On” in “HigH” mode, and the current concentration of gases at “0”
(zero), the 4-20mA loop will output 4 mA.
Gas read – With the 4-20 mA function turned “On” in “HigH” mode, the output will read between 4 mA and 20 mA
depending on the current concentration of gases.
Trouble – With the 4-20 mA function turned “On” in “HigH” mode and the Trouble Fan Setting enabled, the 4-20 mA
loop will output 1 mA or 24 mA depending on the Trouble condition. See Section 5.1 On-Board Diagnostics.
4.5 Configuration “CON”
To change the settings, remove the Philips screw on the front of the CX-xx. Pull off the front cover of the unit. Locate
the MENU and ENTER buttons on the top left of the board.
Figure 4–1 Board View