Accutrol AccuValve AVT3000, Руководство по установке и эксплуатации

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Installation & Operation Manual
- Model AVT3000 & H-AVT3000
Contents of this Manual are Subject to Change Without Notification
Page 25
SECTION 7 – OPTIONAL BACNET MS/TP
BACnet® is a standard data communication protocol designed specifically for building
automation and control networks. The Accutrol AVT3000 Transmitter uses the BACnet MS/TP
(Master-Slave/Token Passing) protocol which is a type of MAC layer implemented using the EIA-
485 signaling standard. The performance of the MS/TP network is heavily influenced by the
network traffic load, the assignment of MS/TP node addresses and the network configuration
parameter
Nmax_info_frames . Additionally, it is imperative the physical network layer is
properly configured (cabling, EOL terminations, bias, etc...) and is verified to be reliable
otherwise the network performance can be compromised.
4.1 BACnet Objects
The Accutrol AVT3000 Transmitter product family supports a collection of BACnet-visible
objects which are defined in the following table.
Point Object Description Present Value Type Units
DE ### Device Instance Write ###
AI1 Airflow Volume Read Volume
AI2 Flash Writes Remaining Read Note 1
AI3 AccuNet Totalized Airflow Volume Read Volume
AV1 Unsubscribed COV Interval Write Sec
AV2 Airflow Volume Measurement Adjust Write %
BI1 AccuNet Status Read Note 3
BV1 Write to Flash Write Note 2
MSI1
Airflow Volume Units Write
1 = CFM
2 = CMS
3 = CMM
4 = CMH
5 = LPS
6 = LPM
Notes:
1. The AVT3000 transmitter has an internal counter which limits the number of times
FLASH memory can be written to. BACnet point AI2 is provided so the number of
remaining flash writes available can be monitored over the BACnet.
2. Writing a value of (1) to the BACnet Object BV1 will cause the transmitter to copy the
active configuration stored in volatile memory (RAM) and write that value to
nonvolatile memory (FLASH). Reference Section 4.1.1 for a detailed description.
3. AccuNet Active Status: 0 = No AccuNet Fault (Inactive)
1 = AccuNet Fault (Active)
Caution: Nonvolatile Flash memory has a limited number of Lifetime Write Cycles,
therefore writing to Flash memory should be used only when necessary.