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Astell Autoclaves/Sterilisers – AMB220 | AMB230 | AMB240 | AMB420 | AMB430 | AMB440 | AMA240 | AMA440
SAFETY AND DOOR INTERLOCKS
This steriliser is fitted with safety interlocks to prevent the
opening of the cover when the chamber is pressurised,
and to prevent pressurization if the cover is not fully
closed.
The UK Health and Safety regulations stipulate that the
closure system and interlocks shall be inspected at regular
intervals by a competent person, and that all operators
shall be trained in the use of the steriliser controls,
operating procedures, and the function of safety devices.
Door interlocks
The door is held in the locked position by an electrically
retracting solenoid locking pin. This is fitted with 4
sensor micro switches arranged to enable the heating
and control system only when the door is closed and the
handle rotated into the locked position. With the cover
open or not fully locked heating is disabled. The locking
bolt system is continually monitored by the control
system.
Inspection and checking
• Unlock and open the door
• Check for smooth action with no grating or crunching
noises, or looseness
• Inspect the locking pins they should slide freely as the
handle is moved
• Operate the door handle. Observe the operation of the
bolts. Operation should be firmly limited by the end
stops, and all bolts must operate in the same manner.
Check that solenoid locking pin operates when handle
is in fully locked position
• Close door and hold shut do not lock. Display should
change to “unlocked”
• Rotate handle, lock and check that locking functions
correctly and prevents further movement of handle.
Display should show ready to start
• Use [door] button to unlock
• If the displays show out of sequence, are unreliable, or
do not show, or if the machine does not lock correctly
turn off and consult a qualified engineer immediately
• In the UK HSE guidance note PM73 requires that such
checks are carried out regularly. To comply with HSE
requirements, instructions regarding testing of these
interlocks must be permanently displayed close to the
sterilizer operator position
OVERTEMPERATURE PROTECTION
This system is intended to protect the chamber, controls,
and, the load, from thermal damage but may not prevent
the water heaters from damage due to overheating.
The system uses an adjustable hydraulic thermostat set to
about 250°C with the adjustment knob sited at the back of
the cabinet behind a cover. The thermostat has a sensor
bulb mounted in a clamp on the heater at the rear of the
chamber. In the event of a temperature rise for any reason
above the set temperature the thermostat operates, this
provides additional boil-dry protection.
There is also a snap-switch cut-out which requires manual
resetting that operates in the extremely unlikely event
that the chamber wall exceeds approx. 150°C if this cut-
out operates there is a serious fault and the chamber will
not heat and must be serviced or repaired by a qualified
engineer.
EMERGENCY UNLOCKING
If the door becomes jammed, or in the case of a power
failure, the door can be manually unlocked.
Warning! The chamber must be below 50°C and
pressure on dial gauge must be zero.
WARNING!
The manufacturers of this steriliser accept no
responsibility for damage which may result in a
load processed in this steriliser in the event of
an overheating fault occurring for any reason.
The over temperature cut-out is provided to
reduce the risk of fire or consequent damage.