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Interface and Intrinsic Safety Guide

TURCK 7/30/2018


Interface and Intrinsic Safety Guide

The excom System

excom is a remote I/O system for use in hazardous locations consisting of power modules, PROFIBUS-DP communication gateways, I/O modules and a backplane rack. The backplane is available in two sizes, with support for 8 or 16 I/O modules. The larger rack (MT18-) also allows for redundant power supplies and/or PROFIBUS-DP gateway cards.

The I/O modules provide the interface to field devices. The backplane distributes power to the I/O from the power supply, with no need for a separate field supply. The gateways, power supplies and I/O cards are simply plugged into the backplane rack, with all power, PROFIBUS-DP and I/O wiring separate from the removable modules. I/O modules may also be changed during operation (“hot-swappable”). The system automatically checks whether a newly inserted module matches the configuration.

When the excom system is used, the PROFIBUS-DP segment coupler SC12Ex must also be used for the interfacing. The coupler is equipped with one standard RS485 interface and two RS485-IS interfaces that allow redundancy. Optional fiber-optic couplers are also available.

The excom system, (including the SC12-Ex segment coupler) can be mounted in Divison 2, Zone 1 or 2 and is FDT/DTM and HART compatible. The field circuits are approved for Division 1 and Zone 0.

Interface and Intrinsic Safety Guide


The DPC-System (Diagnostic Power Conditioner System) is a power supply system for the installation of FOUNDATION fieldbus H1 segments. It provides comprehensive diagnostic functions for monitoring FOUNDATION fieldbus segments, and supports asset management for the entire system. This includes asset management of the physical layer which is extremely valuable.

A DPC system consists of one or more module racks (DPC-49-4RMB) each with up to eight power supply modules (DPC-49-IPS1) and one diagnostic module (DPC-49-ADU). Up to four H1 segments for each module rack can be operated and monitored redundantly. The diagnostic data from the H1 segments is transmitted via the HSE interface module (DPC-49- HSEFD/24VDC) to the higher level asset management system.

The diagnostic module (DPC-49-ADU) is used as a communication and diagnostic interface between the H1 segments and the power supply module. The diagnostics module monitors the electrical parameters and the communication parameters of the H1 segments. Operation without diagnostic module is possible. In this configuration, simple diagnostics are provided locally.

The diagnostic information is collected in the device and transmitted via the HSE interface module to the higher fieldbus level (e.g. to the host) as diagnostic and alarm data. The diagnostic module can be plugged and unplugged during operation (hot swappable).

The DPC system provides complete galvanic isolation; H1 to H1, H1 to 24 VDC power, ADU/DU to H1, and HSE to H1. The DPC system can also be used to supply devices in hazardous classified areas when Fisco power supplies/repeaters or multibarriers from TURCK are used.

TURCK extends its diagnostic power conditioner systems (DPC) with a new interface backplane for single FOUNDATION fieldbus segments. The new DPC-49-1RMB is specially suited for smaller fieldbus installations, and provides a handy alternative to the DPC-49-4RMB multi-segment backplanes.

Like the multi-segment backplanes, the new DPC-49-1RMB features a redundant power supply, as well as a built-in diagnostics via a system alarm relay contact. Based on the established 800 mA supply DPC-49-IPS1, the new backplane supplies power to a single FOUNDATION fieldbus segment. Connections to the host system and to the field are provided via removable 3-pin screw terminals.

Interface and Intrinsic Safety Guide

Communication Signal

The FOUNDATION fieldbus H1 communication signal is a square waveform superimposed on a DC carrier. The frequency of the signal is 31.25 Khz. Although it is not a requirement, most devices derive their supply power from the fieldbus communications cable. The fieldbus specification states that devices must not be polarity sensitive. However, it is good electrical practice to have all devices wired with the same polarities. The voltage range allowed for proper operation is 9 to 32 VDC. A typical fieldbus device will consume 20 mA of current.

Fieldbus Cable Specifications

The specifications for fieldbus H1 physical media are defined by IEC 61158-2 and the ISA-S50.02 Part 2 Physical Layer Standards. The same standard is also listed in the FOUNDATION fieldbus specifications under 31.25 Kbps Physical Layer Profile FF-816-1.4. There are essentially four types of cable designations for fieldbus (see table). Type A cable is preferred for new installations, because it allows for the most versatile lengths. The other cable types are for installations where cable already exists from 4-20 mA systems.
  Type A Type B Type C Type D
Cable Description Shielded, Twisted Pair Shielded, Multi-Twisted Pair Unshielded, Multi-Twisted Pair Shielded, Untwisted Pair
Conductor Size 18 AWG 22 AWG 26 AWG 16 AWG
Maximum Length 1,900 meters (6,232 feet) 1,200 meters (3,936 feet) 400 meters (1,312 feet) 200 meters (656 feet)

Interface and Intrinsic Safety Guide

TURCK’S new interface module cartridge (IMC) series is another innovative breakthrough in process automation: The I.S. barrier is moved from the mounting cabinet directly to the installation, thus making it possible to create further decentralized structures in the installation.
Part Number Description
IMC-Di-22Ex-PN0/24 VDC (NO = normally open) NAMUR sensor, contact with resistor circuitry
IMC-Di-22Ex-PNC/24 VDC (NC = normally closed) NAMUR sensor, contact with resistor circuitry
IMC-Ai-11Ex-i/24 VDC Active transmitter; Current source
IMC-AiA-11Ex-i/24 VDC Passive 2-wire transmitter; Current sink
IMC-A0-11Ex-i/24 VDC Analog actuator, positioner, display
IMC-D0-11Ex/L Pilot light, solenoid valve, 4-wire transmitter
IMC-SG Cover guard
The exceptional compact and rugged device series creates new options and possibilities for the user: In addition to your standard mounting cabinet solution, increase the flexibility of your system by using TURCK interface module cartridges.

• IP 67 protection with screw on connectors
• Mounting in Zone 2 - Application area in accordance with ATEX: II (1) GD, II (3) GD
• Ambient temperature -25° to +70°C
• Standard signals
• Plug & play connection technology, M12 connectors


Interface and Intrinsic Safety Guide

TURCK introduces the new IMS interface module measuring merely 6.2 mm wide. The module may be configured with a laterally mounted DIP switch for added convenience.

This extremely compact module provides complete galvanic isolation, up to 2.5 kV between the input, output and power supply. Galvanically isolated IMS modules are available with dead-zero to live-zero signal conditioning, or one and two channel modules are available without signal conditioning.
Part Number Description
IMS-AI-DI-DI/24VDC 0-20 mA to 0-20 mA
IMS-AI-DI-DU/24VDC 0-20 mA to 0-10 V
IMS-AI-DI-LI/24VDC 0-20 mA to 4-20 mA
IMS-AI-DLI-22-DLI/L 0/4 to 20 mA loop powered dual channel
IMS-AI-DU-DI/24VDC 0-10 V to 0-20 mA
IMS-AI-DU-DU/24VDC 0-10 V to 0-10 V
IMS-AI-DU-LI/24VDC 0-10 V to 4-20 mA
IMS-AI-LI-DI/24VDC 4-20 mA to 0-20 mA
IMS-AI-LI-DU/24VDC 4-20 mA to 0-10 V
IMS-AI-LI-LI/24VDC 4-20 mA to 4-20 mA
IMS-AI-UNI/24VDC Universal mA/V selectable
IMS-TI-J/24VDC Type J thermocouple to mA/V
IMS-TI-K/24VDC Type K thermocouple to mA/V
IMS-TI-PT100/24VDC Pt-100 RTD to mA/V
Modules are also available for temperature detection using Pt-100 technology or other thermo-elements. Those that use Pt-100 technology achieve 0.3 percent of the full scale, and are available with 2-, 3- or 4-wire connections. An analog signal transmitter that achieves 0.1 percent of the full scale completes the IMS line.


• Signal conditioning
• Analog conversion
• Temperature measurement
• UL, Division 2 approved

Interface Modules with FDT/DTM

To simplify device set-up and installation time, TURCK’S interface module (IM) family may now be programmed via a pc or on-board push buttons using FDT/DTM software, along with PACTware. This software allows multiple parameters to be set and saved in a matter of seconds. The ease of use and structure of this system allows asset management ability with trending and data logging of values.

TURCK’s IM modules may be used to monitor the speed of motors, shafts and conveyors, the temperature of RTD’s and thermocouples, and to control or monitor analog signals for linear movement, temperature, pressure, level control or any other device using 4 to 20 mA signals. Intrinsically safe models to control devices in hazardous areas are also available.

All models are equipped with a two-line transflective LCD display, making it easy to read even in very bright light. The modules also incorporate a universal supply voltage and removable terminals, making them easy to install in new or existing systems.

ZENER Diode Barriers

• Temperature monitoring and control of equipment and their surrounding areas with RTD’s and thermocouples
• Load cells
• Control and monitor 4-20 mA transmitters
• Control or monitor all other analog signals for linear movement, temperature, pressure, level control or any other device using 4-20 mA signal feedback NAMUR Sensors and Junctions
• Class I, Class II, Class III, Division 1 and Division 2 FM approved
• Full line of inductive, capacitive and magnet operated inductive sensors
• Numerous sizes and styles are available
• Eliminates multiple cable runs for wiring IS applications

NAMUR Sensors and Junctions

• Class I, Class II, Class III, Division 1 and Division 2 FM approved
• Full line of inductive, capacitive and magnet operated inductive sensors
• Numerous sizes and styles are available
• Eliminates multiple cable runs for wiring IS applications

Intrinsically Safe Pressure Transmitters

• PT4300 pressure transmitters are UL/cUL 1604 (CSA 213) Class I, Division 2, Groups A, B, C and D approved for hazardous area applications.
• PT4400 pressure transmitters are UL/cUL 913 Class I, Division 1, Groups C and D approved when installed with an approved barrier, such as the IM33 isolation module.
• PT4300 and PT4400 sensors incorporate a 316 stainless steel measuring element that permits ranges from 0-10,000 psi, with high burst pressures up to 20,000 psi.
• PT4500 submersible level transmitter is Class I, Division 1 approved when installed with an approved barrier, such as the IM33 isolation module.

Intrinsically Safe R16 Level Probes

• Rated for FM Class I, Division 1 areas