Servomex SERVOTOUGH LaserExact 2950, Руководство оператора

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SERVOTOUGH LaserExact Monitor, Operator Manual 02950001A_1
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5.2.2 Servicing the LaserExact cell
Dust or other contamination on the cell mirrors will reduce the signal level. The
instrument is designed to allow a considerable reduction of the signal level (down to
10-30%) without influencing the quality of the measurements. However, if the signal
level drops below the level of reliable measurements, the LCD shows «Low
transmission», and the cell should be cleaned. The procedure for opening and
cleaning the cell is described below.
1. Make sure that the instrument is switched OFF.
2. Disconnect the sample gas tubes.
3. Check if low transmission is due to poor alignment of the mirrors in the beam
alignment chamber (follow the procedure of Section 3.4). If this procedure
does not improve the transmission level, continue with the following steps.
4. The analyser should be moved to a clean office or laboratory space before
opening the measurement cell. The following procedure requires care and
experience. We recommend you ask your local dealer for assistance.
5. Remove the body of the LaserExact cell from the beam alignment chamber
instrument by unscrewing the four bolts. Note: The cell is heavy! Carefully
lower the body the cell. It is important to move it straight down. Tilting the cell
body could cause damage to the mirrors. The inner rod with the two mirrors
attached to it is now visible. Note: The mirror surface is very fragile. Do not
touch the mirror surface. Doing so is likely to permanently damage the mirror.
6. Clean the mirror surface with clean air or nitrogen (blow dry). If not sufficient
the mirror surface may be rinsed with a non-abrasive detergent (e.g. Acetone
or Isopropanol) and blown dry afterwards. The mirrors should NOT be rubbed
with paper or clothing. This may adversely affect the mirror surface and
subsequently the instrument transmission.
7. Check if the window between the cell and beam alignment chamber is
contaminated. The window is visible through the slot in the upper mirror. If the
window is contaminated contact your local dealer for further assistance.
8. Reassemble the cell by carefully sliding the body of the cell over the inner rod.
Tighten the four bolts fixing the cell body to the beam alignment chamber.
9. Reconnect the sample gas tubes.
10. Switch the instrument ON and check the transmission. If necessary realign the
instrument as described in Section 3.4.
In the unlikely event that mirrors have been damaged; note that single mirrors can be
replaced. This is a more comprehensive procedure so please contact your local
distributor for assistance.