Fluke VT Plus HF, Руководство оператора

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VT Plus HF
Operators Manual
8-30
10.
Zeroing
The VT PLUS HF 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 VT
PLUS HF between automatic and manual zeroing, select the
ZEROING
menu from the
SETUP
menu. The current zeroing mode has a check next to its name. Select the zeroing
mode you want.
Manual Zeroing
When the VT PLUS HF is in manual zero mode, no automatic zeros will occur.
Periodically, it is a good idea to zero the signals on the VT PLUS HF to null any offset
errors in the flow and pressure sensors.
The VT PLUS HF has two different ways to perform a manual zero:
1. Select
ZERO
from the menu, and then choose to
ZERO ALL
or select the signal you
would prefer zeroing from the given list.
Figure 8-19: Zeroing Menu
1. Select the
ZEROING SPEED
button from the tool bar. Choose the preferred plot
from the given list. Just clicking the
ZEROING
button is the same as selecting
ZERO ALL
.
Automatic Zeroing
The VT PLUS HF can be set to automatically zero flow and airway pressure periodically.
This will null offset errors in the pressure transducers. During an auto-zero, the VT PLUS
HF will use 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.