RMF Systems CMS 2, Руководство пользователя

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As a policy of continual improvement, RMF reserves the right to alter the specification without prior notice.
201.028 REV 1 Date of Issue: 18 June 2018
combination makes up a 32-bit integer. For example, the value of such a 32 bit unsigned integer stored in the two
registers 40 and 41 may be calculated using the formula:
𝑣𝑎𝑙𝑢𝑒 = (65536 × ( 𝑟𝑒𝑔𝑖𝑠𝑡𝑒𝑟 40)) + ( 𝑟𝑒𝑔𝑖𝑠𝑡𝑒𝑟 41)
The particle counts are stored in registers 40-55, as shown in Table 6D. There are 8 register pairs; each pair
encodes one count channel as a 32 bit integer, using two consecutive Modbus registers as explained above. The
Counts are per 100ml.
Particle sizes are expressed below according to ISO4406:1999, i.e. equivalent projected area diameter. The sizes
have been chosen so that all supported coding standards (NAS, ISO...) can be derived from them. The counts are
all cumulative.
Differential counts can be derived by subtraction. E.g., the NAS 5-
15μm count could be calculated by subtracting
the ISO 6μm(c) count from the 14μm(c) count.
Number Function Comment
40-41 ≥4µm (c)
42-43 ≥6µm (c) ≥5µm (NAS)
44-45 ≥14µm (c) ≥15µm (NAS)
46-47 ≥21µm (c) ≥25µm (NAS)
48-49 ≥25µm (c)
50-51 ≥38µm (c) ≥50µm (NAS)
52-53 ≥50µm (c)
54-55 ≥70µm (c) ≥100µm (NAS)
Table 6D Particle Count Registers
6.4.1.5 Alarms
6.4.1.5.1 Alarm Mode
The CMS includes two relay outputs that can optionally be used for signaling the state of the unit. These are
normally used in ``stand-
alone’’ applications where the Modbus interface is not used (since a Modbus controller /
PLC already has all the exact results available in digital form and can work with these directly.)
There are a number of preset ``modes’’ that determine the exact function of the relays. Refer to the alarm mode
section for more details (6.3.3.9.2).
These modes are normally set at installation time using our PC software package RMF-View. But it is also possible
to use Modbus to set the operating mode of these relays, by writing the corresponding integer to the alarm mode
register 26.
6.4.1.5.2 Alarm Limits
Settable Upper and Lower limits for particulate contamination are provided.
These are two gr
oups of 8 registers representing the ``Upper Limit’’ and ``Lower Limit’’ for particulate
contamination. These are 64-71 and 72-79 respectively.
These are expressed in terms of the result codes using the same format as in 6.4.1.2. An additional special value
of 0x8000 (hexadecimal representation) is used to signify
a ``don’t care’’ setting for that limit code.
6.4.2 CAN-bus
The CMS supports the major CAN-bus basic message format standards CAN 2.0A (11 bit identifiers) and CAN2.0B
(29 bit identifiers).