CareFusion Alaris 8110 series, Руководство по обслуживанию

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PRINCIPLES OF OPERATION
4-2
Alaris
®
Syringe Module (8110 Series)
Alaris
®
PCA Module (8120 Series)
Technical Service Manual
Both the Syringe and PCA Modules include
display, logic, drivetrain, drive head, plunger,
and force sensor subsystems.
NOTE:
All circuit boards in the Syringe and
PCA Modules are not field repairable and
must be returned to a CareFusion
Service Center for repair.
4.3 DISPLAY BOARD ASSEMBLY
The keypad sends signals to the
microcontroller on the Display Board, whose
function is to manage displayed information.
The Logic Board provides
5V
power to the
Display Board through a
10
-pin connector.
4.3.1 Microcontroller
The Display Board's microcontroller
provides four keypad functions: Channel
Select, Pause, Channel Off, and Restart.
The microcontroller controls the keypad
backlight and the Alarm, Infusing, and
Standby
LED
s.
The microcontroller controls the
LED
display
driver for the Channel Identification
(Channel
ID
) and
7
–segment rate displays.
The microcontroller also drives the scrolling
alphanumeric display that shows module
status (such as "
INFUSION COMPLETE
" or
"
CHANNEL MALFUNCTION
").
The microcontroller performs safety
monitoring and generates alerts (including
the Alarm LED and applicable error
messages) if critical circuitry does not
function properly.
4.3.2 LED Display Driver
The microcontroller communicates serially
with the LED driver for the
8
-digit,
7
-segment
LED
display.
The display driver uses a discrete resistor
for brightness control. Module software
provides three brightness levels: low (
27%
of
full brightness), used when the PC Unit is
operating on battery power; medium (
47% of
full brightness), used when the PC Unit is
operating on
AC
power; and high (
100%
brightness) is the maximum level possible.
Rate:
The display driver controls the five
7
–segment displays used for the Rate
display: three
7
–segment displays and two
small
7
–segment displays (
t
he smaller
displays show fractional digits). The five
displays show infusion rates from
0.01
mL/h
to
999
mL/h. The Rate display is readable in
normal hospital lighting conditions from a
distance of
15
feet and provides a
45
°
viewing angle.
Channel Identification:
The display driver controls the
14
–segment
Channel
ID
display, which can display letters
A
through
H
. The Channel
ID
display is
readable in normal hospital lighting
conditions from a distance of
15
feet and
provides a
45
°
viewing angle.
4.3.3 Comparator/Safety Monitor
The comparator/safety monitor circuit
detects short or open failures of the Alarm
LED
or rate display and sends that
information to the microcontroller. This
ensures correct alarm notification and
prevents the module from displaying an
invalid infusion rate.
4.3.4 Status and Backlight LEDs
A constant current drives and ensures
consistent brightness levels for the three
status
LED
s (Alarm, Infusing, Standby) and
the keypad backlight
LED
.
4.2 GENERAL INFORMATION
(Continued)