Mettler Toledo DP550 Manual De Instrucciones página 6

3 Adjustment
– Connect the Phototrode as described in Paragraph 2.
– Dip the probe into water or in the solvent to be used.
– Lightly depress the adjustment knob (1) and turn it until it snaps into position.
– Adjust the output potential to 1000 ±5 mVDC (100% transmittance) by turning the
knob which has been snapped in place.
– For precise measurements, it is recommended that the warmup time of 30 minutes
be observed.
4 Maintenance
Make absolutely sure that the mirror (4) and the window (3) are always clean. It is best
to clean them with a cotton swab. The probe is resistent to most acids and solvents.
Make sure that the probe is rinsed thoroughly with water after use, especially if alkaline
mixtures which contain chloroform are used. If there is any dulling of the mirror, the
mirror assembly (5) can be replaced easily.
5 Malfunctions and possible causes
No signal
– Mirror (4) or window (3) is dirty.
– Unscrew mirror assembly, connect Phototrode to power supply and check whether
the light is coming through the window (3). If no light is visible, send the phototrode
along with the power unit to the nearest METTLER TOLEDO Service facility.
Signal fluctuations
– These can be caused by air bubbles or solid particles in the sample solution. Vary
the stirrer speed until the air bubbles disappear.
6 METTLER TOLEDO DP550/DP660