Alarm Board; Power Supply; Peripheral Components - GE Giraffe OmniBed Carestation CS1 Service Manual

The ICSBC provides two user accessible I/O ports located at the lower rear area of the display assembly.
One is a USB 2.0 Host with a Type A female connector. The USB port is used for software upgrades with a
USB Flash Drive. The other is a 100Base-TX Fast Ethernet port with a RJ-45 connector. The Ethernet function
is disabled but could be enabled with a future version of software.
The ICSBC has two internal communication and control interfaces. One is the CAN bus communication with
the Alarm Board. The other is with the Giraffe Control Board located in the main electronics enclosure. The
connection to the Control Board is through the 14 pin ribbon cable which contains several control lines and
the RS-485 Bus for serial communication.

1.4 Alarm Board

The primary function of the Alarm Board is to provide visual indicators during alarm conditions. Other
functions include hands-free alarm silence (HFAS), power-fail detection, and power-fail visual alarms. The
Alarm Board is located in the top of the display assembly so it can illuminate the alarm lens and interface to
the HFAS lens.
The Alarm Board is powered by the +12V DC power under normal conditions and the +5V DC STBY power in
power fail conditions. In power fail, the Alarm Board enables a red LED for visual indication.
The Alarm Board has a 32-bit ARM microcontroller that communicates with the host microprocessor on the
ICSBC via the CAN bus. The CAN bus allows the Alarm Board to receive commands from the SBC and provide
status to the ICSBC. When commanded, the Alarm Board will enable or disable the 4 white LED's that
function as a beacon light to indicate the presence of an alarm condition. If CAN communication is lost, the
Alarm Board will indicate an equipment failure by enabling the 4 red LED's and activating the board-
mounted buzzer.
The Alarm Board contains the circuitry that provides the hand-free alarm silence function. The HFAS
function is implemented using infrared (IR) emitting LED's and an IR sensor. The IR sensor measures the IR
signal that is reflected from a hand passing in front of the HFAS lens. The microcontroller contains the HFAS
software to control the IR emitter and digitize the reflected signal. Additional filtering and processing is
necessary to determine if and when a valid HFAS event has occurred. The status of HFAS events are sent to
the ICSBC host microprocessor via the CAN bus.

1.5 Power Supply

The universal input (80-264 VAC) switching power supply converts the line voltage to +5V DC (0.5A max) and
+12V DC (10A max). This power supply can source up to 120 watts. The +5V DC and +12V DC are sent to the
Relay Board for distribution to the other device electronics (Control Board, ServoO2 Board, RS-232 Board, In-
Bed Scale, SBC, and Alarm Board). The two DC voltages can vary by + 10%; the acceptable voltage ranges
are +4.5 to +5.5V DC and +10.8 to +13.2V DC.

1.6 Peripheral Components

The heater isolation transformer isolates the incubator and radiant warmer heaters from the mains voltage.
The primaries mains input voltage comes from the relay board and is switched by safety relay 1. The dual
primaries are connected in parallel for 115 volt operation and in series for 230 volt operation. The isolated
secondary output voltage is always 115 volts and is input to the relay board where it is used by the heater
Service Manual
Chapter 1: Functional Description
Alarm Board
1-5