91518 Multigas Analyzer Service Manual
3-1
Contents
Theory
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Interface PCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Gas Analyzer Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Oxygen Measuring Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Overview
The 91518 Multigas Analyzer is a side stream gas analyzer, measuring real time concentrations of O
2
, CO
2
,
N
2
O and anesthetic agents (halothane, enflurane, isoflurane, desflurane and sevoflurane).
The interface PCBA communicates through a two-way SDLC connection to the Spacelabs Healthcare monitor.
Warning:
If any halogenated anesthetic agent other than halothane, isoflurane, enflurane, desflurane, or
sevoflurane is present, it will be misidentified and/or will interfere with the reported anesthetic
agent concentrations.
Caution:
• When administering anesthetic agents, incorrect agent identification may occur when a mixture
of sevoflurane and enflurane occur in the sample circuit.
• When administering anesthetic agents, always verify your anesthetic vaporizer setting.
Note:
The 91518 Multigas Analyzer automatically identifies which agent is detected, but it cannot measure more
than one agent at a time.
Figure 3-1: 91518 Product overview block diagram
Interface
& Power PCBA
Multigas Module
Rear
SDLC_26-pin
SDLC_9-pin
PD Dev.
Ports
AC
BRICK
DC in
I/O
I/O
Serial / USB
Debug
DC
Serial / Pwr / cntl
Switch
Switch
/LED
AC
Input
Power
On
Gas
Sampling
Front
SDLC Termination
Switch
