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Maintenance
3. Pull out the plastic base over the power cable socket.
4. Remove the defective fuse, see Figure 1 on page 14.
5. Insert new fuse (T 2 A H; 250 V)
6. Replace the plastic base.
7. Plug in the power cord.
8. Switch the instrument on.
7.4 Filter pad maintenance
To determine when the filter mat needs to be replaced, inspect the
filter mat every 3–6 months (in a relatively dust-free environment,
this interval can be longer).
1. Remove any cuvettes and cuvette/sample cell adapter from the
cell compartment.
2. Turn the instrument off.
3. Unplug the power cord.
4. Lift the instrument and check the color of the filter mat. Replace
the filter mat if is dark gray or black.

7.4.1 Filter pad replacement

5. Carefully turn the instrument over and place it on a soft surface.
6. Use a screwdriver (standard or cross-head) to open the
filter grid (Figure 9 on page 126, item 1).
7. Lift the filter grid (Figure10 on page 126, item 1).
8. Remove the old air filter pad and replace it with a new air filter
pad (Figure 10, item 2).
9. Screw the grid back in place.
10. Carefully stand the instrument upright.
11. Plug the instrument in.