SMAR HI302, Руководство пользователя

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HI302 - User’s Manual
8.3
4. How many HI302 modules can be installed on the same H1Channel?
From the H 1 Channel’s perspective, up to sixteen modules can be connected to it, as it is
a passive-MAU device. It must be remembered, that the HI302 module works as a HART
device concentrator, supporting up to 32 HART devices in continuous communication.
The total number of blocks to be supervised, as well as the supervision periodicity, must
be taken into consideration for this dimensioning. The suggestion is for no more than 32
HART devices per H
1 channel, namely,
•
one HI302 module in the multidrop mode, with 8 channels x 4 instruments per channel
or,
•
4 point-to-point HI302 modules, with 8 channels x 1 device per channel.
5. Can other types of devices be installed on the same H1 Channel?
Yes, as long as all limitations and restrictions are considered regarding the time for blocks
and parameters supervising, publication of links, etc. The HI302 macrocycle is very large
because the HIRT block execution takes a lot of time.
6. How many HART devices can be connected to a HI302 module?
Up to a total of 32 instruments (transmitters or actuators), being at most 1 5 (addressed
from 1 to 1 5) for each channel. It is strongly recommended that at most 4 devices per
channel be installed, so that the communication in the multidrop mode is most efficient.
7. What is the difference between the HI302-N, HI302-I and HI302-O Modules?
The three modules work on the same basic hardware and firmware platform, the
difference being on the analog conversion board installed over the main board.
•
On the HI302-N model there’s no conversion plate.
•
On the HI302-I, the circuit converts 4-20mA to FF, through a MAI block.
•
On the HI302-O, the installed circuit converts from FF to 4-20, by using a MAO block.
8. What is the Update Periodicity of the HART variables on the HI302 module blocks?
This period of time depends on a series of factors such as: number of devices per
channel, simultaneous communication entered, communication errors, presence of
another Host in the channel, a device on Burst Mode, etc. Generally speaking, a HART
transaction lasts about 500 ms to be finished. If in one channel there are 4 devices, the
dynamic variables will be updated every 2 seconds on the average.
9. Does the HI302 Module let Portable Programmers to be used, such as the HPC301?
Yes. Since the HPC30 1 is a Secondary Host, it is possible to have it connected to a HI302
channel without any problems, provided this channel is configured as a Primary Host.