Hach LT 200 User Manual page 12

3. Select a 4-character name for the program. Push the left key to
change the character. Push the right arrow key to move the cursor to
the next position. Push OK to save the change.
4. Push or hold down the up and down arrow keys to set the
temperature (37 to 150 °C). Push OK to save the change.
5. Push or hold down the up and down arrow keys to set the time (0 to
480 minutes). Push OK to save the change.
6. Push OK to save the program.
Section 7 Maintenance
C A U T I O N
Multiple hazards. Only qualified personnel must conduct the
tasks described in this section of the document.
N O T I C E
Do not disassemble the instrument for maintenance. If the internal
components must be cleaned or repaired, contact the manufacturer.
7.1 Clean the instrument
Keep the instrument clean to get continuous and accurate operation.
C A U T I O N
Fire hazard. Do not use flammable agents to clean the
instrument.
C A U T I O N
Burn hazard. Do not clean the instrument when it is hot.
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N O T I C E
To prevent instrument damage, do not use cleaning agents such as
turpentine, acetone or similar products to clean the instrument
including the display.
1. Turn the instrument off and disconnect the power cord.
2. When the instrument is cool, clean the surface of the instrument with
a soft, moist cloth and a weak soap solution. Make sure that no water
gets into the instrument.
If the liquid in a sample cell spills or a sample cell breaks:
1. Turn the instrument off and disconnect the power cord.
2. Let the temperature of the heating block(s) and sample cells
decrease until cool.
3. Remove the liquid with a pipette. Do not let the liquid touch skin.
4. Move the liquid to the correct disposal.
5. Remove broken glass using tweezers. Remove any remaining liquid
on the instrument. Do not let the liquid touch skin.
7.2 Measure the temperature of the heating block
Measure the temperature of the heating block to make sure that the
temperature shown on the display is correct.
The temperature shown on the display is the temperature in a closed
sample cell that is filled with a liquid. While the temperature of the
heating block is increasing, the temperature of the heating block, near
the heater, may be greater than the temperature shown on the display.
Tools needed:
• Sample cell (LT 200: LCW906, DRB 200: 2275800)
• Glycerol (anhydrous), 5 mL
• Thermometer, stem-type, calibrated for 95 to 155 °C (203 to 311 °F),
type 67C to ASTM
To measure the temperature of the heating block: