GE Giraffe OmniBed Carestation CS1, Service Manual

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Chapter 1: Functional Description
Humidifier
1-8 Service Manual
board, control flow to the patient compartment. Both valves are opened until the measured level gets close
to the desired set point then one valve is closed. One valve is then cycled on and off as needed to maintain
the desired oxygen levels in the patient compartment. The valve selected is alternated so both valves cycle
about the same number of times. There are 2 fuses between the Servo O2 board and the supply valves that
prevent high current from the board entering the valve housing should a short occur in the supply valves. A
safety valve that shuts off oxygen flow whenever the canopy is raised actuates mechanically by the
movement of the canopy support rail. When the canopy is down the valve is open (canopy up/valve closed).
The safety valve actuates independently of the solenoid type supply valves.
1.9 Humidifier
Refer to the following diagram. Water enters the insulating cylinder (1) through a small hole in bottom.
Steam rises along the heater cartridge protective insert (2) and is channeled between the heater mount (3)
and the ramp block (4) and out the steam port (5).
1.10 System Logs
All system failures are logged to the error log. The error logs are only accessible through the service
interface as described in the “Understanding the Service Interface” on page 4-1. The logs are stored to
persistent medium which preserves log data across power cycles and loss of power. When the log reaches
capacity, the oldest data is removed to provide space for newer data to be added.
3
2
1
5
4
FIGURE 1-2. Humidifier