STAUFF LPM-II-plus, Manual, Page: 71 / 83

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As a policy of continual improvement, STAUFF reserves the right to alter the specification without prior notice.
201.031 Date of Issue: 06 November 2018
11.2.2.4.1 Message: Result Codes
This message is transmitted after each test.
The test result is expressed as a set of codes in the selected Test Format (ISO4406, NAS1638 etc.).
The test result message is always 8 bytes long, with the result codes packed as follows:
Format:
Byte ISO 4406
Code AS4059E Table 2
Class NAS1638/ AS4059E Table 1/
ISO 11218 (Draft) Codes/
Classes
1
≥4µ
Basic Basic
2
≥6µ
- -
3
≥14µ
A 5-15 µm
4
≥21µ
B 15-25 µm
5
≥25µ
C 25-50 µm
6
≥38µ
D 50-100 µm
7
≥50µ
E >100 µm
8
≥70µ
F
NOTE: The “basic” class is the highest of the individual size classes.
ISO4406 only defines codes for the first 3 sizes 4, 6 and 14µm. we extend the concept to cover
the other sizes. This allows limits to be set on the number of large particles, even when using the
ISO 4406 coding system.
11.2.2.4.1.1 Special Values
The result codes use a few “special” values in order to represent codes that are not simple numbers.
The NAS
1638 standard defines classes “00” and “000”, these are classes “cleaner” than class 0. We
represent these using signed integers of value -1 and -2 respectively (these will appear as 255 and 254 if
read as unsigned integers).
11.2.2.4.2 Message: Status
The message is transmitted every 1 secon
d so that it can be used as a “heartbeat”.
However if no test has been performed yet, the LPM will wait until it sees other CAN-bus activity before
sending anything.
Byte Bit Length Type Item
1-4 1 32 Unsigned Test Number
5 1 8 Unsigned Status Code
6 1 8 Unsigned Completion
7-8 1 16 Bitmask Status Flags
Test Number The current Test Number is an auto-incremented integer or can also be set as part of the
Test Start command. This is used to distinguish tests / circuits.
Status Code This is a number used to indicate the current state of the LPM, or a fault code in the case
of a problem being detected. The codes are listed in Table III. This allows a system to
remotely monitor the LPM operation, if desired, allowing more specific diagnostics.
Completion A number between 0 and 100 indicating the progress of the test. This will increase from 0
to 100 during the set test time. It can be used to drive a progress indicator.