Smar’s 302 series makes use of the Fieldbus network system, enabling distribution of the control function to equipment in the field, interconnecting several devices – permitting the user to build control strategies suitable for the application by linking the function blocks.
The function block concept was introduced in order to provide a user-friendly, easily configurable system. The user may easily build and have an overview, of complex control strategies. Another advantage is added flexibility, the control strategy may be edited without having to rewire or change any hardware.
The need for implementation of Fieldbus in small as well as large systems was considered when developing the entire 302 series of Fieldbus devices. They have the common features of being able to act as a master on the network and be configured locally using a magnetic tool, eliminating the need for a configurator or console in many basic applications.
The digital technology used in the 302 series enables the choice of several types of transfer functions, an easy interface between the field and the control room, superior accuracy, stability and several interesting features that considerably reduce the installation, operation and maintenance costs.
LD302 pressure transmitter
The LD302 is a transmitter for differential, absolute and gauge pressure, level and flow measurements. It is based on a field-proven digital capacitive sensor that provides reliable operation and high performance. Pressure ranges covered are from 0-125 Pa to 0-40 MPa (0-0,5 inH20 to 0-5800 psi) - with a 0,075% accuracy of the calibrated range. Calibration accepted from URL to URL/40. Wetted parts are constructed of 316 SS, Hastelloy and tantalum. The assembly is weatherproof, explosion-proof and intrinsically safe.
An optional digital LCD display with associated adjustment switches is offered, with configuration able to be effected via Fieldbus communication, from a PC or by the local adjustment switches (should the display be fitted). The inclusion and deletion of function blocks is supported, and the entire process from sensor through the internal electronics and communication is digital, facilitating the instrument's self-diagnostics and network master capability.
TT302 temperature transmitter
The TT302 is a transmitter mainly intended for measurement of temperature using RTDs or thermocouples but can also accept other sensors with resistance or mV output such as: pyrometers, loadcells, resistance position indicators, etc. The digital technology enables a single model to accept several types of sensors, wide range single-ended or different measurement and an easy interface between the field and the control room and several interesting features that reduce considerably the installation, operation and maintenance costs. The transmitter accepts two channels, ie two measurements. This reduces the cost per channel.
As per the LD302, the TT302 digital LCD display is optional, configuration through Fieldbus communication from a PC or by the local adjustment switches (should the display be installed). Basic accuracy is 0,02% and the dual channel instrument's universal input accepts several thermocouples, as well as RTDs, mV and ohm inputs
FY302 control valve positioner
The FY302 is a control valve positioner for pneumatic valve in a Fieldbus system. The instrument produces a pressure output as required to position a control valve according to an input receiver over the Fieldbus network or internal controller.
Reliable and flexible
Elimination of many mechanical parts seen in other positioners has a number of advantages. These include improved reliability, as there are fewer parts that wear; improved safety, as there are less moving parts and better accuracy therefore there is less deadband from mechanical imprecision.
Position sensing is done without any mechanical contact, virtually eliminating wear and subsequent degradation. FY302 directly senses longitudinal or rotary movement being the Hall effect. The position signal may also be used in advanced control schemes.
Valve characteristics, action, absolute and rate-of-change limits, etc are altered in software instead of a mechanical cam and spring, changing, action or characteristics between line equal percentage, hyperbolic (quick opening) or a freely configurable table may be done remotely by the click of a button. These and other software capabilities make the FY302 truly flexible.
Self-diagnostics
The continuous self-diagnostics of the positioner issues immediate alerts for a range of hardware and software failures as well as any problems with the positioner or valve. This enables maintenance personnel to pinpoint errors instantly - or even before they can cause any harm. The diagnostic data may also be accessed on demand.
The benefit to be had by having access to this information without having to bring the valve or positioner into a workshop for testing is obvious. The time that can be saved by having to test only a few units is significant. Diagnostics enables one to quickly determine if a process problem is due to the valve/positioner or not, without having to do several field visits. Production can be back in operation in minutes.
The diagnostics functions are also suitable for preventive maintenance such as detection of increasing valve deadband and 'stick-slip' operation. There is also a software travel limit switch, which automatically alerts the operator. Features include the digital LCD display option, configuration via PC or local switches (if display option is installed). Then there is function block inclusion and deletion, self-diagnostics and the weatherproof, explosion-proof and intrinsically safe housing. Additional features include low air consumption; direct non-contact position sensing and the software cams offer the ability to change valve characteristics. There is also a range of function blocks to choose from.
FP302 Fieldbus-to-pneumatic signal converter
The FP302 is a converter mainly intended for interface of a Fieldbus system to a pneumatically actuated control valve or a positioner. The instrument produces a 0,2-1,0 kg/cm2 (3-15 psi) output proportional to an input received over the Fieldbus network. The device also offers the optional digital LCD display, remote Fieldbus or local configuration, function block inclusion/deletion and self-diagnostics. It is weatherproof, explosion-proof and intrinsically safe and its universal input accepts several thermocouples, RTDs, mV and ohms. Pressure can be locally (with LCD option) and remotely displayed. The instrument is economical in air consumption, and includes remote indication of loss of air supply.
IF302 current-to-Fieldbus converter
The IF302 is a converter mainly intended for interface of analog transmitters to a Fieldbus network. It receives a current signal, typically 0/4 to 20 mA and makes it available to the Fieldbus system. The digital technology used in the IF302 enables a single model to accept three inputs and also provide several different transfer functions, and an easy interface between the field and the control room. With an accuracy of 0,03%, the converter also offers remote configuration via Fieldbus/local adjustment switches (should the display be fitted). Function block options and self-diagnostics are included, and the instrument is weatherproof, explosion-proof and intrinsically safe.
FI302 Fieldbus-to-current converter
The FI302 is a converter mainly intended for interface of a Fieldbus system to control valve or other actuators. It produces a 4-20 mA output proportional to input received over the Fieldbus network. The FI302 has three outputs, reducing the cost per channel. The same remote/local configuration options, function block options and self-diagnostics options are supported - as per the previously discussed instruments. These include network master capability, in a weatherproof, explosion-proof and intrinsically safe housing.
DF47 intrinsically safe, HI Fieldbus repeater
Equipment is considered intrinsically safe when that equipment and wiring, is unable to discharge sufficient electrical or thermal energy, under normal or abnormal conditions, to cause ignition of a specific hazardous atmospheric mixture which is in its most easily ignited concentration.
The intrinsically safe technology incorporated in the DF47 totally isolates the control network on the hazardous side of the barrier. The incorporation of a Fieldbus repeater provides the means to implement Fieldbus high-speed communications in a hazardous environment - without compromising the safety requirements of explosion-proof wiring. The networks of the hazardous and safe sides of the DF47 are completely independent of each other. The DF47 has a built-in near terminator for the hazardous network; only a single far-termination is required.
Features include the ability to extend Fieldbus networks into hazardous areas, the provision of 100 mA at 14 V to the hazardous network, conformance to the IEC 1158-2/ISA S50.02 standards for Fieldbus, and to FM and CE intrinsic safety standards.
DFI 302 Fieldbus universal bridge
Claimed to be the first ever integrated Fieldbus bridging unit, this device permits communications between Fieldbus ports H1 (31,25 kbps) and high-speed Ethernet (10 and 100 Mbps). It supports hot-standby redundancy in various levels: OLE server, LAS (link Active Scheduler) and Ethernet. Each DFI 302 can directly access 256 I/O, distributed among local I/O modules.
The 32 bit RISC processor-based CPU handles its control and communication tasks through:
* One high-speed Ethernet Fieldbus port at 10 Mbps.
* Four Fieldbus H1 ports at 31,25 Kbps.
* One EIA232 Modbus port.
Completely configurable through the Foundation Fieldbus function blocks, the entire system can be configured using one software package. The DF47 (100 mA) Fieldbus safety barrier can be integrated as a module in the DFI 302, providing IS capability.
DMT
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