Datex-Ohmeda 7100, Technical Reference Manual

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7100 Anesthesia Ventilator
2-16 02/03 1006-0836-000
2.4.6 Monitoring
interface
The breathing circuit monitoring interface (MIA in the Aestiva machine and
VMB in the Aespire machine) is the interface between the patient circuit
sensors (the inspiratory and expiratory flow sensor, the O
2
sensor) and the
ventilator control module. It also passes different switch functions through to
the ventilator control module. These switches are used to show the position
of covers, breathing circuit modules and pneumatic controls in the breathing
circuit.
Respiratory gas flow, to and from the patient, is monitored by measuring the
differential pressure across a variable orifice in each flow sensor. The
pressure transducers for measuring the differential pressure are on the
MIA/VMB. Conditioning circuitry is supplied for these transducers and for
the Oxygen sensor used in the breathing circuit.
Pressure sense tubing and signal wiring is routed from the sensors and
switches in the breathing system to the MIA/VMB. A separate cable, routed
through the breathing system and the machine proper, transfers power and
signals to and from the Control Board.
Figure 2-12 • Breathing Circuit Monitoring Interface Assembly (MIA)
Control Board Connector
O2 Sensor
Connector
ACGO
Connector
Switch / Flow Sensor
Connector
+5V
Regulator
+6.0V
Regulator
-6.0V
Inverter
O2 Amp
O2
Buffer
Insp
Buffer
Exp
Buffer
EEPROM
Clock
Receiver
EMI Filters
and ESD
Suppressors
EMI Filters and
ESD Suppressors
Noise
Filter
ACGO
E2_PWR_ON
SCLK+
SCLK-
INSP_DATA
EXP_DATA
INSP
EXP
O2
O2_DISCONNECT
+12V +12V
BAG / VENT
SW1
SW2
SW3
SW1
SW2
SW3
BAG / VENT
+12V
+5V
EXP_CLK
INSP_DATA
EXP_DATA
INSP_CLK
GND
Inspiratory Pressure
Transducer
Expiratory Pressure
Transducer
GND
+6.0V ANALOG
-6.0V ANALOG
INSP_RET
EXP_RET
O2_RET
CPCVR_OPEN
CANI_REL
BYPASS
CPCVR_OPEN
CANI_REL
BYPASS
Insp
IA
Exp
IA
Adjustable Gain & Offset
GND
EMI Filters
and ESD
Suppressors
Noise
Filter
EMI Filters
and ESD
Suppressors
AB.43.095
Notes regarding VMB:
SW1, SW2, and SW3 are hard
wired at the Control Board
Connector to indicate a Circle
Module.
The CPCVR_OPEN signal is
renamed ABS_ON.
The BAG/VENT and the
ABS_ON signal arrive at the
O
2
Sensor Connector.
The VMB includes a 100 mA
Current Source that supplies
power to the Task Light from
the +12V line.