GE Solar 7000, Service Manual

Page: 96 / 214

TROUBLESHOOTING: Block Theory of Operation
4-10 Solar 7000/8000/View Patient Monitor Revision J
414993-001
Block Theory of Operation
Overview The monitor is capable of displaying up to six or eight different
waveforms at one time on a color or monochrome high-definition, raster-
scan screen. Pop-up window guide user interactions on screen without
obstructing the display of real-time patient data. Software upgrades are
downloaded using a laptop computer or from the central station using
the Unity Network.
Main Processor PCB The main processor PCB performs all the major processing of the Solar
7000/8000/View monitor and controls many other complex functions of
the monitor. It controls the display processing, remote display, remote
alarm, and all communication functions. More details are listed below.
Display Processing
Circuitry The main section of this PCB is the display processing section that is
controlled by a 25-MHz microprocessor. It accepts processed or
unprocessed patient data from one of the communication networks and
processes it to be displayed on the monitor. The main microprocessor
receives control signals directly from the keycap PCB or remotely from
the various communication connectors. Two sets of analog video signals
are generated: one drives the CRT and the other drives the remote
display.
Remote/Local Display
Circuitry The main processor PCB also provides circuitry to buffer the real-time
waveforms from the Solar 7000 monitor to a remote color or monochrome
display. Likewise, the Solar 8000 processing unit and SolarView remote
display controller provide the same circuitry to a compatible local
display. RGB video signals and horizontal and vertical sync signals are
available from the video display connector.
Remote Alarm Circuitry The remote audio signals are generated for the remote audio/alarm
(RMT ALM) connector. The remote audio signal has an amplitude of
approximately 1 V p-p and a frequency response of 160 to 16 kHz.
Two sets of relay signals are also provided to drive the remote alarm
interface circuitry. Two sets of relay signals are provided in order to
implement a fail-safe scheme in which one relay signal set indicate alarm
condition, and the other indicates that the monitor is active. Both relay
control signals are actuated in the normal MONITOR ACTIVE/NO
ALARM state. This insures that a failure in the relay circuitry will cause
an alarm condition to occur. Assertion of the RESET* signal or removal
of power to the monitor forces the alarm control signals to the inactive
state.
An associated, separately powered remote alarm indicator unit is
required to complete the implementation of the fail-safe alarm scheme.
This unit must have MONITORING SYSTEM ENABLED/DISABLE
control which is used to confirm that the monitor has been turned OFF. If
this switch is in the ENABLED position and the monitor’s active relay
becomes deactuated, an alarm condition occurs. Indicators can be
provided on the remote alarm unit to identify the specific type of alarm
condition currently occurring.