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2022.11.18
•
REV. 1
• MASS FLOW METER OPERATING MANUAL
19
Polling Mode
Polling mode and a unit ID of
A
is default, unless otherwise requested. Polling the device returns a single line of data for
each request. To poll your device, simply enter its unit ID.
Poll the device:
[unit ID]
Example:
a
(polls unit A)
You can change the unit ID of a polling device by typing:
Change the unit ID:
[current unit ID]
@=
[desired unit ID]
Example:
a@=b
(changes unit A to unit B)
The unit ID can be changed via the device’s front panel (
). Valid unit IDs are letters A–Z, and up to 26 devices
may be connected, as long as each unit ID is unique.
Streaming Mode
In streaming mode, your device automatically sends a line of live data at regular intervals. Only one unit on a given COM
port may be in streaming mode at a time. To put your device into streaming mode, type:
Begin streaming:
[unit ID]
@=@
Example:
a@=@
(puts device A into streaming mode)
This is equivalent to changing the unit ID to “
@
”. To take the flow meter out of streaming mode, assign it a unit ID by typing:
Stop streaming:
@@=
[desired unit ID]
Example:
@@=a
(stops and assigns unit ID of A)
When sending a command to a device in streaming mode, the flow of data will not stop while the user is typing. This may
make the commands you type unreadable. If the device does not receive a valid command, it will ignore it. If in doubt,
simply hit
and start again.
The default streaming interval is 50 ms, but this can be increased by changing Register 91 while the device is in polling mode:
Set streaming interval:
[unit ID]
w91=
[number of ms]
Example:
aw91=500
(streams new data every 500 ms)
Taring
Before collecting flow data, be sure to tare your meter.
Manual taring can be accomplished through two separate commands for flow and pressure. Taring flow sets the zero
flow reading and must be done when no flow is passing through the flow meter:
Tare flow:
[unit ID]
v
Example:
av
(sets flow reading to zero)
For devices equipped with a barometer, the second tare aligns the internal absolute pressure sensor with the barometer
reading and must be done with the flow meter open to atmosphere:
Tare absolute pressure:
[unit ID]
pc
Example:
apc
(requires optional barometer)
Collecting Data
Collect live flow data by typing the
[unit ID]
command or by setting your flow meter to streaming. Each line of data
for live flow measurements appears in the format below, but the unit ID is not present in streaming mode.
A +13.542 +24.57 +16.667 +15.444 N2
ID Absolute Pressure Temperature Volumetric Flow Mass Flow
Gas
Single spaces separate each parameter, and each value is displayed in the chosen device engineering units (
).
You can query the engineering units of the serial data frame by typing:
Query live data info:
[unit ID]
??d*
Example:
a??d*
(returns the data frame descriptions)
Additional columns, including status codes (
), may be present after the last number. The unit ID appears in
the data frame only when the flow meter is in polling mode.
Summary of Contents for FMA-1600A Series
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