Introduction to the Siemens 6ES5928-3UB12 CPU 928B
When your S5-135U or S5-155U system demands reliable, high-speed control, the 6ES5928-3UB12 delivers. This Siemens CPU 928B central controller is engineered for both single and multiprocessor operation, supporting up to four CPUs in one rack. Its universal design ensures very fast bit processing and very fast word processing, making it a versatile choice for demanding automation tasks.
From a cost perspective, the CPU 928B reduces total cost of ownership by enabling efficient program execution and minimizing cycle times, which translates to higher throughput and lower energy consumption per operation.
Key Features and Technical Specifications
The 6ES5928-3UB12 is packed with features that enhance performance and flexibility:
- Cyclic, time-controlled (9 different timebases), real-time controlled, interrupt-driven (hardware interrupt), and delayed processing modes.
- User memory capacity up to 64 x 2^10 bytes (EPROM or RAM) for code and data blocks.
- Integrated DB RAM of 46 x 2^10 bytes for efficient data handling.
- 2048 flags, 8192 S flags, 256 timers, and 256 counters.
- Program blocks (PB) 256, sequence blocks (SB) 256, function blocks (FB) 256, and function blocks FX 256.
- Data blocks (DB) 256 (253 freely available) and data blocks DX 256 (253 freely available).
- Organization blocks OB 1 to 39 for operating system interfaces.
- Supply voltage: 5V ±5% and 24V +25%/-17%.
- Current consumption: 5A typical at 5V, 760mA max at 24V.
- Backup voltage: 3.4V, backup current: 20μA typical at 25°C.
- Transmission rate of serial PG interface: 9600 bps.
- Degree of protection: IP 00.
These specifications directly impact cost efficiency: the low backup current reduces battery replacement frequency, and the generous memory capacity minimizes the need for external storage modules, lowering overall system cost.
Applications and Use Cases
The 6ES5928-3UB12In multiprocessor configurations, it can handle complex tasks by distributing workload across up to four CPUs, improving system responsiveness and reducing downtime. For cost-sensitive operations, the ability to run multiple programs without additional hardware reduces capital expenditure.
Installation and Setup
Installing the 6ES5928-3UB12 is straightforward. The CPU consists of two PCBs (basic and expansion boards) in double Eurocard format, screwed together and linked via connectors—do not separate them. The basic board connects to the S5 bus via two backplane connectors. The front plate width is 2 2/3 standard plug-in stations. Ensure proper mounting to maintain the IP 00 rating, which means no protection against dust or moisture, so install in a clean, dry enclosure.
Maintenance and Reliability
Regular inspection of the CPU and its environment is essential. Check that the cooling vents are unobstructed and that ambient conditions stay within the specifications of the S5-135U/155U central controller. The mode switch and momentary-contact switch should be tested periodically to ensure reliable operation. Following the manufacturer's manual for maintenance procedures will extend the life of the unit and prevent unexpected failures, directly reducing maintenance costs.
Compatibility and Integration
The 6ES5928-3UB12 is designed for the S5-135U/155U central controller and supports the S5 bus. It includes an integrated serial PG interface and an optional serial interface via submodules (V.24, TTY, RS 422A/485). From version 6ES5928-3UB12, it also supports the SINEC L1 interface. This flexibility allows integration into various industrial networks without additional converters, saving on interface hardware costs.
Troubleshooting Common Issues
If the CPU fails to start, check the mode switch position and the RUN/STOP LEDs. An overall reset (momentary-contact switch down) clears all RAM areas, which can resolve memory corruption issues. If the program does not execute correctly, verify that the user memory submodule is properly seated and that the program blocks are correctly configured. For persistent issues, consult the official Siemens documentation or contact AutoDCSTech for support.
Product Support and Availability
The 6ES5928-3UB12 is available from AutoDCSTech. Please verify current lifecycle status and availability with our team before ordering. We are ready to assist with your automation needs.
Availability & Condition at AutoDCSTech
| Part Number | 6ES5928-3UB12 |
|---|---|
| Availability | In Stock |
| Condition | New |
| Warranty | One Year |
| Origin | Germany |
