SIEMENS 6ES7341-1CH02-0AE0

What is 6ES7341-1CH02-0AE0 and where is it used?

The 6ES7341-1CH02-0AE0 is a Siemens SIMATIC S7-300 CP 341 communication processor with an RS-422/485 interface. The module extends an S7-300 system with serial point-to-point communication to third-party devices, computers, or other automation components. Typical applications include the connection of measuring instruments, control systems, scanners, printers, serial machines, legacy systems, and Modbus devices. Siemens specifies support for ASCII, 3964(R), RK 512, and printer communication; for Modbus applications, Siemens provides documentation and application examples for operation via the RS-422/485 version. This makes the module particularly useful when existing S7-300 installations need to remain in operation, be expanded, or be returned to service quickly after a failure.

Overview of the key technical specifications and their significance

The module operates on 24 V DC, requires a maximum of 100 mA from L+ and 70 mA from the backplane bus, and has a typical power loss of 1.6 W. The electrically isolated RS-422/485 interface improves robustness in industrial environments. Transmission rates range from 0.3 kbit/s to 115.2 kbit/s, while cable lengths of up to 1,200 m are possible depending on parameter settings and baud rate. Telegram lengths of up to 4,096 bytes are supported.

For control cabinet applications, the compact dimensions of 40 × 125 × 120 mm, a weight of approximately 300 g, and an operating temperature range of 0 to 60 °C are also important. For maintenance personnel, the key advantage is that the module is designed for reliable serial communication within existing S7-300 architectures and provides straightforward diagnostics via the RxD, TxD, and SF LEDs.

Product status, lifecycle status, and obsolescence

Siemens currently classifies the 6ES7341-1CH02-0AE0 as a spare part. For the SIMATIC S7-300 / ET 200M platform, milestone PM400 (Product Phase-Out Announcement) was set to 1 October 2023, while PM410 (Product Cancellation) was scheduled for many affected components on 1 October 2025. Siemens states that, after these milestones, components are no longer available as regular new products and are instead supplied only as spare parts or supported through repair strategies.

For modernisation projects, Siemens identifies the CM PtP RS422/485 HF, 6ES7541-1AB00-0AB0, as the corresponding S7-1500 migration solution. This is a verified migration option, but not a direct drop-in replacement within an unchanged S7-300 rack. For operators, this means that long-term availability is increasingly secured through repair services, spare-part stockholding, and planned migration projects.

Available EICHLER services and their practical relevance

For this module, EICHLER offers repair, exchange, used, and new units. This is particularly valuable for obsolete or discontinued communication processors.

Repair is the preferred option when the existing configuration and application logic need to remain unchanged. Exchange is the right choice in the event of an urgent breakdown, as a fully tested replacement unit can be supplied before the defective module is returned. Used units provide a practical solution when original hardware is required quickly and a retrofit project is not yet planned. New units are particularly relevant for building spare-part inventories or proactively securing critical systems.

According to EICHLER, repaired, replacement, and exchange units are cleaned, refurbished, function-tested, and supplied with a minimum 24-month warranty. These services are available exclusively to business customers.

What exactly is the 6ES7341-1CH02-0AE0?

The 6ES7341-1CH02-0AE0 is a CP 341 communication processor for the SIMATIC S7-300 with an RS-422/485 interface. It is designed to establish serial point-to-point communication between an S7-300 controller and external devices or computer systems. Typical applications include situations where existing installations must continue communicating with serial devices, measuring instruments, printers, or third-party systems.

Does the 6ES7341-1CH02-0AE0 support Modbus RTU?

Yes. Siemens provides Modbus RTU application examples and parameterisation guides for the RS-422/485 version of the CP 341. This is particularly relevant when an S7-300 system needs to communicate with third-party devices via RS-485. For operators, this means the module is suitable not only for traditional Siemens protocols but also for connecting to widely used serial field devices and third-party components.

Which protocols does the module support natively?

The CP 341 natively supports ASCII, 3964(R), RK 512, and the printer driver protocol. An important limitation is that 3964(R) and RK 512 cannot be used via RS-485 on this variant. For many retrofit and legacy applications, this broad protocol support is valuable because it allows both traditional Siemens communication methods and flexible ASCII communication to remain in service.

Is the 6ES7341-1CH02-0AE0 still available as a new product or only as a spare part?

Siemens currently classifies the module as a Spare Part. On the referenced EICHLER product page, it is also listed as New at the time of writing. From a procurement perspective, this means the product is in a late lifecycle phase, but inventory stock and alternative sourcing options may still be available. For critical installations, it is advisable to consider not only immediate availability but also repair and exchange strategies.

Is there a Siemens-recommended successor for modernisation projects?

For migration to the S7-1500 platform, Siemens recommends the CM PtP RS422/485 HF, 6ES7541-1AB00-0AB0 as the corresponding communication module. This is an official migration path, but it is not a direct 1:1 replacement without modifications to the hardware and software environment. Companies that need to maintain an S7-300 installation today typically rely on repair, exchange, or spare-part stockholding, while long-term modernisation projects are usually planned around this newer module family.

What should I pay particular attention to during wiring and commissioning?

Key points include the correct A/B line assignment, selecting RS-422 or RS-485 in the parameter settings, configuring the correct serial communication parameters, and ensuring a proper GND connection. Siemens explicitly warns against connecting the cable shield directly to GND, as this may damage interface modules. At the same time, GND must be routed correctly on both communication partners. It is also important to remember that maximum practical cable length decreases as baud rate increases, so wiring and parameterisation should always be considered together.

Can the module also be used in distributed S7-300 architectures?

Yes. Siemens states that the CP 341 can also be operated in a distributed ET 200M environment using an IM 153. This is particularly useful in existing machines where serial communication needs to be integrated within a distributed I/O architecture rather than directly at the central CPU. As a result, the module remains a practical solution even in more complex legacy automation systems.