Hill-Rom Isolette C2000 - Electrical System

Theory of Operation
Chapter 3: Theory of Operation
Theory of Operation
Electrical System
Sensor Module
The sensor module P.C. board provides the interface from the patient and
incubator requirements that the infant incubator must support. The module
reads and processes the following parameters: temperature, oxygen, humidity,
and weight information collected from external sensors and cables. This
information is periodically updated and is transmitted to the main controller
upon request.
The sensor module P.C. board does not require manual calibration. Calibration
is performed automatically and periodically during normal operation. To
provide safe monitoring and control, both the temperature information and
oxygen information have redundant circuitry to prevent single-fault failures.
All
signals are transmitted through serial data communication.
The sensor module is connected to a sensor P.C. board which has some of the
parameters required for the system: air temperature, oxygen, humidity, and fan
operation.
Power Suppl
Power to the sensor module P.C. board is provided through connector J4,
providing +12V AC for use in this system. Voltages are regulated by U21, U19
and U15, providing +5V, digital +5V and analog -5V, respectively. U20
provides a precision +5V source to be used in analog signal conversions.
Sensor Position Detection
Hall effect sensors are used to. sense magnets in the slide mechanism. The
sensors U9 and U12 are used to determine the calibration position. Sensors
U16 and U22 are used to determine the hood position during normal operation.
The output is normally high. These devices provide a /ow output if a significant
south pole magnetic field is applied to their surface.
Remote Light Alarm Indicator
DSI provides an alarm indication with a high field of view and is illuminated
by a positive signal (RMLITE) at the gate of transistor Q3.
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Isolette® Infant Incubator Service Manual (man223rf)