SMAR HI302, Руководство пользователя

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Operation
5 . 10
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If the polling is enabled, the HIRT block associated with the HART device will notice
this alteration and will go to OLD DATA, sending the command 38.
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After sending the command, the HIRT block begins to update the parameters by
getting in IDENTIFICATION and UPDATING. During the UPDATING process, the
ST_REV of the HIRT block will be incremented, indicating that the data was updated
and must be read again.
IMPORTANT
The polling commands don’t increment the block ST_REV.
Conclusions on the STATIC REVISION:
1. The ST_REV cannot be used to monitor HART device data alterations.
2. If the applicative writes on the HVT block, it may ignore the increment done on the
HVT block ST_REV, as well as the corresponding HIRT block increment.
3. If there is no writing on the HIRT block and the ST_REV was changed, the device
information was updated and a new reading should be done in the HIRT and HVT
blocks.
HART RESPONSE CODE Conversion to STATUS FF
The RESPONSE CODE of the last transaction with HART devices is mapped to the
DEVICE_STATUS, RESP_CODE and COMM_ERR parameters of the HIRT block. In
order to use the information about the device’s general status, the DEVICE_STATUS is
converted into a corresponding STATUS FF to feed the parameters that have STATUS.
For example, the PV_MA can be separated into PV_MA.STATUS and PV_MA.VALUE.
The PV_MA.STATUS represents the actual condition in which the device provides the
PV_MA.VALUE parameter. See the table below:
STATUS HART bit DEVICE_STATUS parameter Status Foundation Fieldbus converted
7 Device Malfunction Bad:DeviceFailure:NotLimited
0 Primary Variable Out of Limits Bad:UncertainNonSpecific:iNotLimited
2 Loop Current Saturated Uncertain:SensorConvNotAccurate:NotLimited
1 Non-Primary Variable Out of Limits Uncertain:Subnormal:NotLimited
3 Loop Current Fixed GoodNonCascade:GoodNCNonSpecific:Constant
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If the block is set at OS, all the parameter will assume the Bad:OutOfService:NotLimited
status.
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If the device stops the communication and the block status goes to NOT RESPONDING ,
all the status go to Bad:NotConnected:NotLimited.
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If there is no error or alert condition to be informed, the status will assume the following
status:
GoodNonCascade:GoodNCNonSpecific:NotLimited.
“BYPASS” Mode
The BYPASS mode was created to make it possible for the HART messages to be sent to
any device, through simple writing on a parameter called BYPASS_REQ_N (N is the
channel number, from 1 to 8). Every parameter is a chain of 100 characters where the
HART messages must be written to be sent to the device. The written content on the
parameter is entirely sent to the channel configured on the HIRT block, as soon as the
channel is free. Thus, the application must include in the message the preambles, the