Dräger Fabius, Instructions For Use Manual, Page: 46 / 232

Operation Concept
46
Instructions for Use Fabius MRI SW 3.n
Total Flow Meter
The total flow meter serves two purposes. The total
flow meter provides a reference of the total fresh
gas applied to the breathing circuit. (Flow rate mea-
surements for each individual gas, N
2
O, AIR and
O
2
, are provided by their respective electronic flow
indicators.)
Should a fault develop in the electronic flow sens-
ing, digital display, or power circuitry, the total flow
meter is still functional. The measurement will indi-
cate the total flow rate prior to the fault condition.
To adjust the fresh gas ratios while under the fault
condition, shut off all flows (O
2
may be left on), and
then restore each gas flow individually. For exam-
ple, start with 2 L/min O
2
. The total flow meter will
read 2 L/min.
If 1 L/min of N
2
O is needed, open the N
2
O flow con-
trol knob until the total flow meter reads
3 L/min: 2 L/min O
2
plus 1 L/min N
2
O.
NOTE
The total flow meter is calibrated for a 50/50 mix-
ture of N
2
O and O
2
. The accuracy of the flow meter
may degrade with other gas mixtures. (See the
Technical Data section for specifications.)