Fluke VT Plus HF, Operator'S Manual

Page: 86 / 134

VT Plus HF
Operators Manual
7-8
Problem Possible Cause Corrective Action
Unit calibration is incorrect If problem persists, call
Service.
Tidal Volumes are erratic
in bi-directional breath
detect mode Breath detection threshold
set too low. Noise from
ventilator is causing "false"
breaths. Set the breath detection
threshold to a higher value.
Tidal volumes different
than expected. User's expected value was
incorrect. Review expectations.
Flow baseline drifts,
causing a false non-zero
flow reading when flow was
actually zero. Zero the flow reading.
Consider using the auto-zero
mode.
VT PLUS HF is out of
calibration.
If possible, verify calibration
with a 3-liter calibration
syringe. Ensure gas settings
are correct. With the
VT
PLUS HF in the bi-directional
breath detect mode and the
gas correction mode set to
ATP, stroke syringe such
that flows are near the mid-
range for the flow sensor.
Compare the
VT PLUS HF
tidal volume to calibration
syringe volume. If difference
is out of specification, return
unit for calibration.
Gas settings are incorrect. Review VT PLUS HF gas
settings.
Correction mode is set to
BTPS or STPD instead of
ATP. Set gas mode to appropriate
setting for your application.
Most applications may
require the ATP mode.