Description Of Safety Features - Pharmacia Biotech MultiTemp III 18-1106-33 User Manual

7. Detailed Description
7.4 Description
of safety
features
18
General cut-off
The heater, the compressor and the circulation pump can be
switched off by a relay built into the unit. This general cut-
off will be activated if a malfunction is detected by the safety
sensors.
When the general cut-off switch is activated, the circulator
can only be restarted after the cause of the indicated fault has
been eliminated. The display will show when this has occur-
red. The circulator can then be re-started by pressing the
Reset key.
Protection against over-heating
A built-in temperature limit switch protects against uncon-
trolled heating of the bath liquid by activating the general
cut-off if this limit is exceeded. (This safety device is indepen-
dent of the control temperature sensor that regulates the set
working temperature.)
The temperature cut-off limit is set on the dial at the rear of
the circulator. This has a range of 20 to 95 °C. You should
select a cut-off limit that is 5 to 10 °C above the set working
temperature. If the temperature rises above this limit, the
general cut off is activated and the following error message is
displayed
down to below the cut-off limit, the following code is
displayed
The built-in temperature limit switch also senses low levels of
coolant. If the liquid level falls and exposes the heating ele-
ment, the temperature will rise above the temperature limit
cut-off level and the general cut-off will be activated. Top up
with coolant to remedy this situation.
The same two error messages shown above will be displayed.
Restart the unit by pressing
(Regular topping up with the liquid coolant is recommended,
See Section 4.1, Start-up.)
. After the bath liquid has cooled
.
.