Fluke Biomedical VT Plus HF - Manual (Page 114)

VT Plus HF
Operators Manual
4-30
Zeroing
The Analyzer can be zeroed either automatically or manually. Zeroing corrects the flow
and pressure sensors for offset to get a more accurate reading.
To switch the Analyzer between automatic and manual zeroing:
1. From the
Setup menu, select the Zeroing menu. The current zeroing mode has a
check next to its name.
2. Select the desired zeroing mode—Manual or Automatic.
Manual Zeroing
When the Analyzer is in manual zero mode, no automatic zeros occur. Periodically, it is a
good idea to zero the signals on the Analyzer to null any offset errors in the flow and
pressure sensors.
The Analyzer has two ways to perform a manual zeroing:
1. Select
Zero from the menu.
2. Choose Zero All or select the signal to be zeroed from the given list.
fec114.bmp
Or
1. Click the
Zeroing Speed button on the toolbar.
2. Choose the preferred plot from the given list.
3. Click the
Zeroing button; this is the same as selecting Zero All .
Automatic Zeroing
The Analyzer can be set to automatically zero flow and airway pressure periodically. This
nulls offset errors in the pressure transducers. During an auto-zero, the Analyzer uses
pneumatic valves to temporally switch flow ports for the zero. Do not use this option if
there is flow in both flow ports. A zero can be forced by manually zeroing a signal, even
if automatic zeroing is turned on.