ENG_3167.XML
The Ex modules are available as associated equipment for the automation of chemical plants. They can be used for instrumentation and control applications.
Fields of application:
- Chemical/petrochemical industry
- Gas industry
- Offshore technology
- Transport (e.g., oil tankers, tank trucks)
- Automotive industry (e.g., in paintshop)
- Power supply, power distribution etc.
- Power stations
- Specialized mechanical engineering (e.g., printing machines, industrial cleaning machines).
The modules may not be used in areas subject to explosion hazard, unless they are additionally protected by another type of protection (e.g., pressurized enclosure).
The modules are approved for the connection of intrinsically-safe sensors and actuators located in Zone 1 or Zone 2 of areas subject to explosion hazard.
The modules can be used:
- In the SIMATIC S7-300 programmable controller
- In the ET 200M remote I/O device, can be used as distributed I/O for all SIMATIC S5/S7/505 programmable controllers and as a standard slave on all PROFIBUS DP networks
ENG_3172.XML
Characteristics
- Shares system technology with the other S7-300 modules, which means that they can be used together in one configuration.
- Galvanic isolation on the module.
- Protected against polarity reversal by coding.
- Sensors and actuators are supplied via the module.
- Direct wiring of the module inputs and outputs, without switch amplifier or transmitter supply units.
- Software-based rewiring is possible.
- Diagnostics-capable modules.
- Reduced planning, installation, and documentation overhead.
- Less space required in switchrooms.
- Can be connected to all SIMATIC automation systems and as a standard slave to all PROFIBUS DP networks when used in ET 200M
System configuration
Intrinsically-safe and non-intrinsically-safe circuits are galvanically isolated on the module. Sensors and actuators are supplied with power via the Ex modules.
The color of the terminal block on the Ex bus module is blue. This marking is normally prescribed in DIN VDE 0165 for intrinsically-safe circuits. Equipment thus marked must not be used for other purposes.
For example, sensors and actuators certified as intrinsically safe can be connected to the Ex input/output modules.
In addition to Ex modules, other modules can be used in a configuration. In this case, you must ensure that the LK 393 cable guide is used for wiring the Ex modules.
The following prerequisites must be satisfied when interconnecting intrinsically-safe equipment and associated equipment:
Associated equipment (S7-300 Ex modules)
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Field device + cable
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U0
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<
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Umax
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IK
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<
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Imax
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P
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≤
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Pmax
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Ca
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≥
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Ci + Ccable
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La
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≥
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Li + Lcable
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Key
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U0:
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No-load voltage
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Umax:
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Maximum voltage
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Ik:
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Supply current
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Imax:
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Maximum current
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P:
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Power
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Pmax:
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Maximum power
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Ca:
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Maximum permissible capacitance
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Ci:
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Internal capacitance
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La:
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Maximum permissible external inductance
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Ccable:
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Cable capacitance
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Li:
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Internal inductivity
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Lcable:
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Cable inductivity
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Certificates
ATEX approval
The SIMATIC S7 Ex modules have the Ex nA [ib] [ibD] IIC approval. Intrinsically-safe equipment for Zone 1/21 and Zone 2/22 may be connected. The license applies to all potentially explosive gas mixtures in Groups IIA...IIC. The safety-related limit values can be found in the certificates of conformity.
FM approval
The requirements of the FM approval FM CL.1, DIV2, GP.A, B, C, D, T4 are fulfilled.
Reference manual Ex I/O S7-300, ET 200M
The manual gives an overview of the topic "Explosion protection". It gives the reader comprehensive information on the topic of "Explosion protection". The following subjects are covered:
- Relevant standards and regulations;
- Primary and secondary explosion protection;
- Types of protection.
The manual also provides information needed for the use of the Ex I/O. Among others, the following topics are introduced:
- Construction of Ex plants.
- Installation in hazardous areas.
- Possible uses of the S7-300 Ex I/O: central (S7-300) and distributed (ET 200M to SIMATIC or as standard slave).
- Planning and configuration documentation.
ENG_89114.XML
The primary task of analog Ex modules is to isolate the intrinsically-safe circuits in the hazardous area from the non-intrinsically-safe circuits of the programmable controller.
The intrinsically-safe type of protection offers the following advantages:
- Problem-free replacement of intrinsically-safe equipment during operation.
- Easy measuring and calibration of the measuring distance even during operation.
- Live-line working at intrinsically-safe circuits is possible without plant downtimes.
- No complex enclosure designs (such as flameproof enclosures).
- Intrinsically-safe equipment from different manufacturers can be interconnected.
- Proven type of protection in the chemical industry.