Technical data
-15- 
1. Press key 
SPAN 
INFO 
 for at least 3 seconds to activate the AutoCal program. During the whole 
procedure the current interface provides 2.0 mA and, the fault LED flashes slowly. The 
display shortly reads CodE. 
2.  Now enter the numeric access code 0011. Use keys
ZERO
TEST
and
SPAN
INFO
to change the figure at the 
current position, and confirm by means of key 
QUIT
MENU
. 
3.  After correct entering, the display shows the current measurement value and the message 
SPAN alternately. The transmitter now waits for a clear rise of concentration. When the 
measurement value remains constant during a defined time interval (after a fixed time of 
2 minutes), the value is used to update the sensitivity (display SAUE). This updates the 
calibration data successfully. The transmitter, however, does not return to detection mode yet, 
since the presently supplied test gas concentration would activate an alarm. The transmitter 
remains in calibration mode until it recognizes a falling gas concentration and then a 
stabilization of the display value. The display alternately reads ZERo and the current 
measurement value. Once the value has stabilized, the transmitter returns to detection mode. 
If the unit does not notice a reduced gas concentration resp. a stabilized measurement value, it 
returns to detection mode after max. 3 minutes. 
At any time the AutoCal program can be shortened by long-term pressing key 
SPAN 
INFO 
. The display 
shortly reads SAUE and the measurement value is accepted directly as the sensitivity update. 
To leave the AutoCal program without sensitivity adjustment, press key 
SPAN
INFO 
only briefly. The 
display shortly reads ESC. 
The following error messages may occur during the adjustment: 
Display  Meaning  Fault LED
CAL 
ERR.1 
No rise of test gas concentration noted. 
CAL 
ERR.2 
Test gas signal is unstable. 
CAL 
ERR.3 
Sensitivity is beyond the allowed tolerance 
range. 
flashing 
quickly 
The error messages have to be confirmed with key
QUIT
MENU
. The transmitter returns to detection mode 
without new calibration. The calibration procedure has to be repeated. 
Service Menu and Extended Service Menu 
Activation of service menu 
The service menu allows to select and to change all important parameters of the CC28. Entering the 
service menu interrupts the detection mode; the transmitter turns to service mode, and the alarms are 
de-activated. The special status "Service" is indicated by the fault LED flashing slowly and by a 
current output signal of 2.4 mA. If you do not hit any key within one minute, the transmitter 
automatically leaves the service mode and returns to detection mode. 
!
All parameters changed in the service menu refer to the currently set type 
of gas ! 
Should you wish to change type of gas and
 parameters, set the new type of gas first, 
before parameter changes for this gas can become effective.  
The service menu can be called in two different extensions. 










