Maintenance
Page 22 of 72 Pages
9023927 - 2nd edition - May 2007
Calibrating the unit
— Ensure that the sensor is warmed up before it is calibrated. Warming-up time: see
the Instructions for Use for the DrägerSensor.
— The Polytron 7500 can be calibrated by the operator on site.
—
For critical applications,
the calibration intervals are to be defined in accordance
with the recommendations in EN 50073
1)
or. EN45544-4
2)
and national regula-
tions.
Note the calibration sequence!
●
First check the zero point and calibrate it if necessary, immediately after this,
check the sensitivity and adjust it as necessary.
— Never calibrate the sensitivity before calibrating the zero point.
— Calibration cannot be carried out if the date and time are not set.
●
Setting the date and time, page 48.
— Calibration menu, page 41 to page 39
— Zero gas and calibration gas: See the related information in the Instructions for
Use for the DrägerSensor.
Setting up the unit
●
Individual settings can be made:
— via the keypad in menu mode
— via the HART interface,
— with the Dräger Hand Held Terminal (DHHT)
1)
EN 50073 – Guidelines for selection, installation, use and maintenance of devices for the
detection and measurement of flammable gases and oxygen.
2)
EN 45544-4 – Electrical devices for the direct detection and direct concentration measure-
ment of toxic gases and vapours – Part 4: Guidelines for selection, installation, use and
maintenance.
Caution:
Calibration gas must not be inhaled. Risk to health!
Care must be taken about the risks which can arise when using test gas; hazard
instructions and safety advice must be observed.
For details, see appropriate Safety Sheets.
Note:
After setting up the unit automatically with the copy function of the Dräger
Hand Held Terminals, the plausibility of the settings must be checked.
