Sutron Accububble 56-0131-50-1, Руководство по эксплуатации и техническому обслуживанию

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avuC
where a is the address, v is the data value, u indicates the units,
and C is the CRC-16 encoded into 3 ASCII characters. Both v
and u have the format of a polarity sign (
+
or
−
) followed by up
to seven digits, including a decimal point. The CRC-16 is
always the last three characters which are never a numeric digit.
The u indicates the units of the measurement. When u is 0, the value has units of feet of water.
When u is 1, the units are psi. When u is 9, the units depend on a user entered slope and offset. u
can also take on additional values after a field calibration has been performed. The following table
summarizes all the values of u.
0 units are feet of water
1 units are psi
2 units are kilopascals
3 units are cm of water
4 units are meters of water
5 units are mm of water
9 units depend on user-entered scale and offset.
If the field calibration offset is non-zero, then one of the following values of u will be returned:
10 units are feet of water with non-zero field calibration offset
11 units are psi with non-zero field calibration offset
12 units are kilopascals with non-zero field calibration offset
13 units are cm of water with non-zero field calibration offset
14 units are meters of water with non-zero field calibration offset
15 units are mm of water with non-zero field calibration offset
19 user units with non-zero field calibration offset
(psi + field calibration offset)
∗
user scale + user offset
set by XE or XS set by XUU set by XUU
If the unit has had its calibration modified at a standards lab other than at Sutron, then the value
returned for u will have one hundred (100) added to it. In other words, if the XC command has
been utilized to set the calibration scale factor to other than 1 or the calibration offset factor to other
than 0 then 100 will be added to the units indicator.
In most cases, you will not set up the recorder to store this units identifier. It is provided in
response to the standard measure command to eliminate confusion as to the computation used to
determine the final value.
Making a Concurrent Measurement with CRC-16 (CC command)
The command to tell the AccuBubble to make a concurrent measurement with CRC-16 check on the
data is:
aCC! where a is the address character, and CC is the command to
make a concurrent measurement with a CRC-16 check on
the returned data
The concurrent measurement with CRC-16 command was first defined in version 1.3 of the SDI-12
specification. Therefore the data recorder will have to be SDI-12 version 1.3 or higher compliant
before it can be expected to issue this command and automatically handle the reply to collect data.
You can also issue the command yourself. In reply, the sensor will respond with
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