Environmental Express HotBlock CAL 3300 - Manual (Page 12)

HotBlock Temperature Settings:
The pre-set factory “Control Point” temperature is 115°C. Factory tests have shown that this temperature is “sea level safe.”
Liquids in uncovered, polypropylene tubes should not boil at this setting. If watch glasses are used, this setting should be
lowered to avoid boiling. The block temperature should be optimized for the specific digestion conditions. PLEASE NOTE that
the block temperature is different than the temperature of the liquids being digested. The temperature of the liquid contents of
the digestion cup will vary with:
A.
The material being digested.
B. The number of samples being digested.
C. The air movement of the digestion area.
D. The addition of a watch glass.
Note: The maximum use temperature of the polypropylene cup is 130
C. Also please note that the temperature display is
not the temperature of the sample. Sample temperature will almost always be 5-15
 less than the display temperature.
Adjusting the Temperature of Your HotBlock:
1. Turn the HotBlock on and wait until the display shows the current block temperature.
2. Press and hold the
✱ key. The display wills how the set point temperature. The temperature can be cahnged
to the desired valued by pressing the ▲ or ▼ keys while pressing the
✱ key.
Tuning Your Hotblock:
Each Hot Block should be tuned at the temperature at which it is to be operated. Tuning enables the Hot Block to achieve
its set point tempera- ture without any overshoot. Tuning of the Hot Block is done at the factory at 115°C. If the block is
operated at a temperature significantly different from 115°C, it may be advisable to re-tune the block to prevent
overshooting the set point temperature. To tune the Hot Block with the CAL 3300 controller, follow these steps:
1. Tuning should be started when the block is near room temperature.
2. Turn the Hot Block off and back on.
3. Wait until the block displays the current temperature, then press the
 and  keys together until “tune” appears on
the display.
4. Press the
 and  key together to change the display from “off” to “on”.
5. Press the
 and  keys together until the display flashes once.
6. It is now in autotune mode. The display will alternate between the rising temperature and “tune” until it reaches
your set point.
7. After the unit has reached your set point temperature, repeat steps 3 through 5, this time changing the “tune”
mode from “on” to “off” in step 4.
The block is now tuned. No other action by the operator is required. The block may be turned off and on and the tuning
will be set.
Safe-Sample TM Temperature Protection:
Your HotBlock is protected from runaway temperatures by a fail-safe alarm system. In the unlikely event that the heating
system fails to respond to the controller, the Safe-Sample
TM system will automatically shut the system off and sound an
audible alarm. This alarm sequence occurs if the actual temperature of the block reaches a temperature that is fifteen
degrees higher than the set point temperature. If this should occur, the HotBlock will stop heating, preventing the loss of
samples. The HotBlock must be turned off, then turned back on to reset the alarm. If the alarm sounds, see the trouble
shooting section of this manual, pages 12-14
Call 1.800.343.5319 Environmental Express • 11
Adjusting the Temperature of Your HotBlock TM
HotBlock Operation Guide