MeloAuto-Trusted PLC & DCS Parts Supplier
This central processing unit serves as the core controller for Siemens SIMATIC S5 automation systems. It executes user logic for industrial processes and machine control applications. Therefore, it delivers reliable real-time control for manufacturing and processing plants.
Physical and Processor Specifications
The Siemens 6ES5942-7UA12 measures 25.0 cm in length and 18.0 cm in width. Moreover, its CPU weight equals approximately 1.10 kg for rack mounting. A single 48-pin male connector links this CPU to the S5 backplane. Additionally, the processor includes built-in communication ports and memory expansion capability.
| Parameter | Specification |
|---|---|
| Brand | Siemens |
| Full Model | 6ES5942-7UA12 |
| Category | CENTRAL PROCESSING UNIT (SIMATIC S5) |
| Dimensions (L x W x H) | 25.0 cm x 18.0 cm x 5.5 cm (9.84″ x 7.09″ x 2.17″) |
| CPU Weight | 1.10 kg (2.43 lbs) |
| Backplane Interface | 1 x 48-pin Male Connector (S5 Rack) |
| Power Supply Input | 5 VDC from Backplane (1.2 A Typical) |
| Power Consumption | 6.0 W (Typical) |
| Processor Type | 16-bit Microcontroller (24 MHz) |
| Program Memory | 64 kB RAM (Battery Backed) |
| Data Memory | 32 kB RAM (Retentive with Battery) |
| Backup Battery | 6ES5980-0UA11 (Lithium, 5 Year Life) |
| Execution Speed | 0.5 µs per Boolean Instruction |
| Built-In Digital I/O | 16 Inputs + 16 Outputs (Local) |
| Digital Input Type | 24 VDC (Sink/Source) |
| Digital Output Type | Transistor (0.5 A) |
| Communication Ports | 1 x RS-232 (Programming) + 1 x RS-422 (Point-to-Point) |
| Supported Protocols | AS511 + SINEC L1 |
| Baud Rate Range | 9600 to 115200 baud |
| Expansion Capability | Up to 4 S5 Expansion Racks (Maximum 2048 I/O) |
| Programming Software | STEP 5 |
| Programming Languages | Ladder Diagram (LD) + Instruction List (IL) + FBD |
| On-Board Components | 1 CPU IC + 3 Memory Chips + 2 UARTs + 1 RTC + 16 Input Optocouplers + 16 Output Transistors + 16 Flyback Diodes + 6 Protection Diodes |
| Operating Temperature | 0°C to +55°C (32°F to 131°F) |
| Mounting Type | S5 Rack (Single Slot) |
| Status Indicators | 1 Green LED (Power) + 1 Green LED (Run) + 1 Red LED (Fault) + 1 Yellow LED (Battery Low) + 16 Green LEDs (Inputs) + 16 Green LEDs (Outputs) |
Energy Storage and Data Retention Features
The Siemens 6ES5942-7UA12 stores energy using six onboard capacitors. Specifically, four tantalum capacitors filter logic power for the CPU and memory circuits. In addition, two electrolytic capacitors provide hold-up energy during backplane power dips. Furthermore, a replaceable lithium battery retains all program and data memory. Consequently, this CPU preserves critical control logic for up to five years.
Built-In I/O and Communication Capabilities
You will find 16 digital inputs and 16 digital outputs built directly onto this CPU. For instance, the inputs accept 24 VDC signals from standard industrial sensors. In addition, the transistor outputs drive small relays, solenoids, and indicator lamps. Moreover, the RS-232 port supports programming and HMI connectivity directly. Likewise, the RS-422 port handles point-to-point communication up to 500 meters. Thus, this CPU operates as a complete standalone controller without additional modules.
Scan Performance and Memory Features
This CPU executes Boolean instructions in just 0.5 microseconds. In addition, the 64 kB program memory stores complex ladder and FBD applications. Moreover, the 32 kB data memory holds process variables and retentive values. Furthermore, built-in I/O points reduce system cost for smaller applications. Therefore, the Siemens 6ES5942-7UA12 suits both compact and distributed S5 configurations.
Installation and Diagnostic Indicators
Six red and green LED indicators provide operational status at a glance. First, a green Power LED lights when the 5 VDC backplane supply is present. Second, a green Run LED flashes during normal program execution. Third, a red Fault LED indicates hardware or software errors. Finally, a yellow Battery Low LED warns when the backup battery needs replacement. Additionally, 16 green LEDs show input status, and 16 more show output status. Thus, you can diagnose system health instantly without external tools.
WeChat
Scan the QR Code with wechat