Fail-Safe Cutoff Valve Calibration - BIO-MED DEVICES IC-2A Service Manual

d. Remove orange plug from inspiratory time capacitor test port (item 44).
Connect a 0 – 60 psi gauge to the inspiratory time capacitor test port. Turn
the OFF/ON switch to ON. Using a screwdriver adjust the inspiratory time
variable resistor (item 24) to obtain a maximum reading of 25 psi on the
gauge. Turn the OFF/ON switch to OFF, remove the gauge, and replace the
orange plug on the test port.
e. Remove orange plug from expiratory time capacitor test port (item 46).
Connect a 0 – 60 psi gauge to the expiratory time capacitor test port. Turn
the OFF/ON switch to ON. Using a screwdriver adjust the expiratory time
variable resistor (item 25) to obtain a maximum reading of 16 psi on the
gauge. Turn the OFF/ON switch to OFF, remove the gauge, and replace the
orange plug on the test port.
f. Connect a 0 – 100 cmH
connector (item 16). Turn the OFF/ON switch to ON. On the rear panel,
rotate MAX. PRESSURE control knob fully counterclockwise to set maximum
pressure needle valve at maximum.
maximum pressure variable resistor (item 29) to obtain a maximum reading of
60cm H O on the gauge.
2

FAIL-SAFE CUTOFF VALVE CALIBRATION

The purpose of fail-safe cutoff valve calibration is to set the valve such that it operates
within the following parameters (listed in order of importance):
a. Cutoff pressure is as close to 30 psi as possible without exceeding it.
b. Delay in delivery of a full and immediate bolus of gas when the IC-2A
Ventilator is turned on is as short as possible.
c. Oscillation (opening and closing) is minimal.
The fail-safe cutoff valve circuit consists of the blue fail-safe cutoff valve (item 33), and
the fail-safe variable resistor (item 27). The fail-safe variable resistor is connected with
red line tubing between the output of the fail-safe cutoff valve and Port 2 of Gate 6. To
calibrate the fail-safe cutoff valve, perform the following procedure:
a. Connect a patient breathing circuit to the Ventilator.
Gauge (refer to paragraph 5.9). Place the CYCLE/MANUAL switch (item 1) in
the CYCLE position, and place the NORMAL/SIMV switch (item 8) in the
NORMAL position.
INSPIRATORY EFFORT control (item 10) so that a negative 1 to 2 cmH
pressure will trigger an inspiratory cycle.
control to 1.0 second, the EXPIRATORY TIME control to 2 seconds and the
FLOW RATE control to 75.
b. Slowly decrease the external ventilator logic supply pressure at the source to
25 psi.
O test gauge to the EXHALATION VALVE line
2
Turn the OFF/ON switch to ON and adjust the
Using a screwdriver, adjust the
Zero the Pressure
Set the INSPIRATORY TIME
O of
2
32