Technical data

-11-
Detection Mode
In detection mode the display shows the current gas concentration.
The display reading is always identical with the display of the remote control connected!
The detection is provided by continuous monitoring. Exceeded thresholds (only for model CC28 DA)
and ambiguous sensor signals are recognized immediately and reported visually by the CC28.
Features of the electronics like parameter memory or sensor function are permanently monitored.
During trouble-free operation the green LED “ON“ is lit, the yellow fault LED is not lit.
!
To indicate that the CC28 is in detection mode the display alternates every minute to
unit and type of gas.
Falling Below Detection Range
Values below the zeropoint are indicated as figures with negative sign. Depending on the
measurement value the current interface provides outputs between 4.0 and 2.8 mA.
Deviations of the detection range by – 7.5% or more are indicated by the permanently lit fault LED
and the display reading ____ alternating with the negative value. The current interface provides a
permanent output of 2.8 mA.
Deviations of the detection range by – 7.5% or more are indicated by the permanently lit fault LED
and the display reads permanently ____.
In case of deviations beyond the detection range of the transmitter circuitry the current interface
provides an output of 1.2 mA.
Exceeding Detection Range
Detection ranges which are exceeded between 100 % and 112 % are indicated by
----
in the
display, alternating with the measured value. Depending on the measurement value the current
interface provides outputs between 20 and 22 mA.
Should 112 % be exceeded, the unit activates the ambiguity alarm. The display flashes
----
and the
current interface provides an output of 22 mA.
Touch Keys
The functions of the touch keys at the transmitter and at the remote control is identical. The same
applies to the display at the CC28 D, CC28 DA and the remote control.
Check of Display, LED and Buzzer
Press
ZERO
TEST
briefly in detection mode to activate the check of the display and LEDs. All LEDs are
activated for 2 seconds, and all segments of the display (8.8.8.8) are shown. For the CC28 DA the
alarm LEDs and the buzzer are activated additionally.
Display of Operational Parameters
During detection mode press key
SPAN
INFO
briefly for the automatic indication of the following operational
parameters one after the other.
This order of readings will also appear after turning the transmitter on.
Display / Example Meaning of display
1a
LEL
Measuring unit (indication in % LEL)
1b
UOL
Measuring unit (indication in Vol.%)
2
CH4
Type of gas
3
SCAL 100
Detection range (full scale in “measuring unit”)
4
CLMAS 80.0
Calibration gas concentration (value in “measuring unit”)
5
A1 20.0
Alarm threshold (value in “measuring unit”)
6
A2 40.0
Alarm threshold (value in “measuring unit”)
7
AM"b. oN
Automatic reset of ambiguity alarm (display reading only,
if „on“)