Hach HT 200 S, Basic User Manual

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English 11
Press key 3 under OK to confirm the entered digestion term.
Enter the digestion temperature
The digestion temperature is determined by the boiling point of the
substance to be digested.
Press
key 1 to adjust the digestion temperature in 5 °C increments over
a temperature range of 40 °C to 150 °C or 170 °C.
Press
key 3 under OK to confirm the entered digestion temperature.
Influence of the acid concentration on the temperature
reached in the sample containers
Note: The programmed digestion temperature for the digestion of
aqueous solutions with diluted acids and lyes (boiling points of 100 to 110
°C) is the temperature that is reached in the reaction tubes or cuvettes
during the digestion process. The temperature in the thermostat block
may be up to 20 °C higher!
For the digestion of semi-concentrated to concentrated acids (boiling
points of 150 °C and above), the temperatures reached in the reaction
tubes or cuvettes are higher than the programmed digestion
temperature.
In this instance, the temperatures in the reaction tubes or cuvettes are
equivalent to the temperatures in the thermostat block.
Enter the digestion time
Press key 1 to adjust the digestion time (time) in 5 minute increments
over a range of 5 to 240 minutes.
Press
key 3 under OK to confirm the entered digestion time.
Position (first,, 2. position etc.) of the user-specific
programs in the main menu
Press key 1 to specify the required position (1–9) on the display.
Press key 3 under OK to confirm the entered position.
Open the user-specific digestion programs
Press key 4 under the arrow symbol in the main menu to show
additional menu items:
Press the key under the relevant digestion term to select the
corresponding digestion program.
Note: This menu only opens if user-specific digestion programs have
been programmed.
Variation (VAR) of user-specific digestion programs
User-specific digestion programs are varied using the VAR menu.
Press key 2 under VAR in the main menu.
The Digestion term , Temperature , Digestion time and Position
parameters can be varied by the user.
Select the digestion program to be varied
Press key 1 under the arrow symbol in the main menu to show
additional menu items.
Press the keys under the relevant digestion term to select the digestion
program to be varied.
Selected
digestiontem
perature
(°C)
Temperature (°C) in the reaction tubes/
cuvettes for digestions of: Thermostat
block
temperature
(°C)
Aqueous solutions
with diluted acids and
lyes
Semi-concentrated to
concentrated acids
40 40 41 41
60 60 62 62
80 80 84 84
100 100 110 110
120 120 134 134
130 130 146 146
135 135 152 152
140 140 158 158
150 150 170 170