Xylem FDO 925/STM, Руководство по эксплуатации, Страница: 7 / 11

7 / 11
Storage 2.5
Always store the sensor in the check and storage vessel (FDO
®
Check) at a temperature in the
range 0 … 50 °C (32 … 122 °F).
3 Maintenance, cleaning, replacement
General maintenance instructions 3.1
Handling of the cap Despite its exterior robustness, the sensor is a high precision optical
instrument. Therefore, special care should be taken when doing any
maintenance or cleaning work:

Dirt and moisture under the sensor cap can affect the functioning and
shorten the service life of the sensor cap. Therefore, make sure the
working environment is clean and dry prior to removing the sensor
cap.

Please do not touch the outer sensor membrane with your fingers.
Touch the sensor cap at the sides only (arrows in figure on the left).

Avoid any great mechanical stress of the sensor membrane (pressure,
scratches).

Exposure to light, particularly daylight, of the interior of the sensor cap
will, by-and-by, affect the measurement characteristics and shorten
the service life of the sensor cap. Therefore, the interior of the sensor
cap should not be exposed to direct sunlight. Avoid any exposure to
light that exceeds the extent required for necessary maintenance and
cleaning activities. Store dismantled sensor caps in a light-protected
environment only.
Exchanging the sensor cap 3.2
Before removing the sensor cap, observe the general maintenance instructions (

chapter 3.1).
To exchange the sensor cap, proceed as follows:
Removing the
sensor cap
1. Pull the sensor out of the sample.
2. Clean the outside of the sensor (

chapter 3.3.1).
3. Unscrew the protective hood from the sensor by hand.
4. Thoroughly clean and dry the sensor head once again.
5. Grasp the sensor cap on the sides (arrows in figure on the left) and
remove it by pulling it away from the sensor in a straight upward
direction.
Caution:
Do not push any tools or other sharp objects between the sealing
surfaces. This would damage the sealing surfaces and sealing ring.