HART communication*1 is a means of transmitting multiple signals by superimposing long-standard 4-20 mA DC analog signals on digital signals.
The figure below is an example of connecting field instruments and upstream devices using HART communication compatible VJA1/H, VJH1/HC signal conditioners. With these signal conditioners, you can output analog control signals as well as TAG and other measuring information from the field instruments to the upstream devices, and at the same time output analog signals to recorders and other monitoring devices. Additionally, the upstream devices can perform zero point/span adjustment and set various parameters on the output devices in the field (HART communication enabled control valves, etc.).
Note: This requires that the devices on both the field and DCS sides can send and receive HART signals, and the parameters that can be set depends on the specifications of the devices performing HART communication.
*The above configuration also allows for D-series nest-housed converters (DA7, DC7).
*1: HART stands for "highway addressable remote transducer."
HART was put forward by Fisher-Rosemount Corp. (USA) as an open standard for industrial control field networks. There is currently an organization called the HCF (HART Communication Foundation). Used extensively throughout the world, the standard defines a communication protocol through which digital signals are superimposed on analog signals, and transmitted.
Products
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Compact Plug-in Type JUXTA VJ Series |
Compact Plug-in Type JUXTA VJ Series
- Compact design for space saving
- Universal input
- Comes standard with 2 isolated current outputs (4–20 mA DC/4–20 mA DC)
- Globally compatible power supply (85–264 VAC/DC, 12–36 VDC)
- Standard withstand voltage of 2000 V
- Compliance with international safety standards
- Relaying HART communication signals (VJA1/H, VJH1/HC)
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| Nest Type for DCS JUXTA D Series |
Nest Type for DCS JUXTA D Series
- High affinity with DCS systems
- Easily maintainable card format
- Mixed mounting of Electronic and Pneumatic signal conditioners
- Designed to minimize usage of aluminum electrolyte capacitors
- Standard second output
- Relaying HART communication signals (DA7, DC7)
