Leica Biosystems ASP200 S - Manual (Page 13)

13 Leica ASP200 S
2.3 Safety features on the instrument
The Leica ASP200 tissue processor is equipped with numerous safety func-
tions and with sophisticated software control mechanisms. These ensure
that the specimens remain undamaged in the event of a power failure or
other malfunction during the infiltration process and that the infiltration is
completed successfully.
Overpressure protection
• When power is off the air pump and air valves default to a safe condition
(retort vented, no pressure generation).
• If the pump is not stopped at the correct moment during the pressuriza-
tion, the power supply is interrupted by a separate electronic circuit.
• In addition, there is a safety relief valve that vents all excess air pump
output to atmosphere.
Overcurrent protection
• Overcurrent conditions are protected against by both the main fuse and
the separate heating power fuses.
Overheating protection
An error is indicated and all heating is stopped by the microprocessor –
control if the instrument detects any of the following conditions:
• Abnormally high temperature (>75 °C)
• Contradictory results of the temperature sensors
• Failure of one or more heating power control components
• If the microprocessor fails to interrupt heating power, independent tem-
perature limiting hardware circuits limit the temperature rise to a safe
level.
• If the temperature limiting circuits malfunction, an independent hard-
ware thermal fuse circuit cuts power to the heating elements.
Over vacuum protection
• The vacuum system is not capable of generating a dangerous vacuum
condition.
Overcurrent protection
• Overcurrent conditions are protected against by both the main fuse and
the separate heating power fuses.
2. Safety