Terumo BCT Trima Accel, Руководство по обслуживанию

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Sensor System
The sensor system is made up of multiple sensors and detectors that monitor pressure, fluid levels, leaks,
door position, lock status, and platelet line composition.
The input for sensor systems consists of variable analog information, and the input for detector systems
consists of binary on/off information.
The sensor system is made up of the following:
•
Two pressure sensors
• Two reservoir level sensors
• The RBC detector
• The anticoagulant (AC) detector
• The leak detector
Motion Feedback Systems
Optical encoders and Hall-effect sensors are used in various subsystems as a feedback loop. These sensor
systems are often paired together, where the primary signal is obtained from one sensor and must match
the secondary signal obtained from the other sensor.
Optical encoders are used by the pumps, the valves, the centrifuge, and the door lock system. All of these
are monitored by the control system except for the door lock system, which is monitored by the safety
system. They function by sensing interruptions in a light beam, counting these interruptions, and
sending that data to the feedback system.
Hall-effect sensors are used as part of the feedback loops for the safety system, and one is used to give door
position information. The Hall-effect sensors are used in the centrifuge motor, the pump housing
raceways, and the door closed sensor. All of these are monitored by the safety system except for the door
closed sensor, which is monitored by the control system. The Hall-effect sensors function when a
transducer senses a magnetic field and then converts that field sensing to an electrical signal that is sent to
the feedback system. The safety system counts these pulses to compare against what the control system
sees with the optical sensors.
There are closed loop and open loop conditions to the feedback systems. Closed loop is the default
condition that uses sensor-derived feedback to directly control the system. An open loop condition
removes the sensor-derived information from the feedback loop.
Sensor System
Trima Accel
®
Automated Blood Collection System • Service Manual 1-19