BD BACTEC FX40 - 1.3.2 Control Electronics; 1.3.3 Incubation Subsystem; 1.3.4 Vial Agitation; 1.3.5 Measurement Subsystem

BD BACTEC™ FX40 Instrument User’s Manual
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1.3.2 Control Electronics
The instrument has several controllers that are responsible for control and analysis of the following:
• Temperature measurement and control
• Built-In-Test functions
• Agitation motor control
• Illuminating station and system indicators
• Monitoring vial presence and door open sensors
• System communications
• User interface
1.3.3 Incubation Subsystem
The incubation subsystem is designed to maintain the temperature of the contents of any culture vial in
any station at 35.0 °C ± 1.5 °C. The temperature is achieved by forced air convection over the media
vials. Incubation hardware includes blowers, heaters, and temperature sensors. The incubation
system heats air according to the temperature setpoint and actual temperature measurements.
1.3.4 Vial Agitation
Vial stations are agitated so that their fluid contents achieve a homogeneous distribution of nutrients
and microbial by-products. Vials are arranged in separate row modules that are coupled by a gang
linkage to a motor. The motor causes each row module to agitate over a range of 0° to 20° relative to
horizontal.
1.3.5 Measurement Subsystem
The measurement subsystem activates the sensor in the bottom of a media vial optically. The
measurement consists of illuminating the sensor with an LED and collecting fluorescent light back from
the sensor with a photo detector. The collected data is processed, normalized and compensated for
thermal variation. Measurement is performed and processed by the Row Board.
1.3.6 Vial Presence Sensing
Each station has a vial presence sensor that immediately detects the insertion or removal of vials. This
allows users to place vials in any location, or to assign stations through vial entry. Station indicators
immediately reflect the changed status. Vial presence sensing is performed by the Row Board.
1.3.7 Station Indicators
LED indicators (shaped like crescents) located above vial stations indicate vial status and are
illuminated when the door is opened. Station indicators are controlled by the Row Board.
1.3.8 Tablet PC / Touchscreen
The user interface is presented on a color tablet PC. The tablet screen features a capacitive
touchscreen that enables you to perform actions and operations simply by touching buttons and fields
shown on the screen. The tablet PC also performs positivity analysis. One tablet can control up to four
BD BACTEC™ FX40 instruments in a cluster.