37
Astell Autoclaves/Sterilisers – AMB220 | AMB230 | AMB240 | AMB420 | AMB430 | AMB440 | AMA240 | AMA440
STERILISING – STAGE PARAMETERS
Example for 123.0°C
Monitor time
This is the maximum time in stage before a fault is
triggered. Must be greater than the stabili sterilize
time. Usually 60 minutes for 15 minutes sterilize time.
Print interval
See above.
Sterilization time
This is the time for the sterilizing period. Typically 15
minutes at 121°C.
Sterilization temperature
This is the temperature for the sterilizing period. E.g.
123.0°C actual value depends upon, the load and required
sterilization conditions.
Temperature
Drain /chamber
123.0°C
Load
123.0°C
(Load only shows if load sensed probe is available)
MEDIA HOLDWARM
If media hold warm is required at the end of the cycle,
then hold warm should be set to on in the cool stage
cycle settings.
The hold warm system is designed to allow sterilisation
of media loads, with a holding stage during the cooling
process that maintains the temperature of the load and
chamber warm enough to permit pouring of the melted
media. The media will be kept warm for up to 48 hrs. The
autoclave may be set to operate overnight with a media
load, in the knowledge that it will contain a usable load
when opened in the morning, or later in the day.
COOLING LOCK SETTINGS
During cooling inside the chamber, the load cools slower
than the chamber temperature and gives up heat to the
chamber walls. This means that the chamber will reach
80°C before the load so (unless load sensed timing is
fitted) the cooling lock setting will need to be below the
temperature.
It is possible to set the cooling locks in a simple
way as shown below, but they are ideally set using a
thermocouple (T/C) and digital thermometer with the T/C
sealed inside the chamber immersed in the liquid load.
This is quicker and more accurate but is normally carried
out by a service or commissioning engineer requiring use
of a thermocouple entry adaptor, and details are in the
service manual.
To set the cooling lock without a thermocouple, a
laboratory liquids thermometer reading to 100°C is
required.
Load the chamber with the desired load, and make a
first approximation of cooling lock temperatures. 80°C
is suggested for both the program and pre-set settings.
Start the cycle and allow it to complete. Very carefully
remove the load, using insulating gauntlets and suitable
face protection in case the load is too hot. Immediately
measure the temperature of the liquid in the load
container that was nearest the centre.
Record this temperature and compare it with the desired
opening temperature (80°C suggested).
The measured temperature is likely to be higher than the
desired temperature. Adjust the program and thermostat
cooling lock settings as required and repeat the cycle
with the same load, open, measure and re-adjust if
required. Continue until the desired cooling lock release
temperature is reached.