Siemens 6ES7312-5BE03-0AB0 CPU 312C | Compact PLC with MPI

Product Overview

• Model: 6ES7312-5BE03-0AB0 | SIMATIC S7-300 CPU 312C
• Compact CPU with integrated 24V DC power supply.
• On-board I/O: 10 digital inputs and 6 digital outputs.
• Includes 2 fast counters (10 kHz) for precise counting.
• 32 KB working memory, MMC required for program storage.
• Firmware version V2.6, hardware version 01.
• Ideal for small to medium automation applications.

Technical Specifications

• Supply Voltage
  • Rated: 24V DC (20.4V to 28.8V range).
  • External protection: Miniature circuit breaker C-type 2A or B-type 4A.
• Current Consumption
  • Rated: 500 mA; no-load: 60 mA typ.
  • Inrush current: 11 A typ; I²t: 0.7 A²·s.
• Power Loss
  • Typical: 6 W.
• Memory
  • Work memory: 32 KB (non-expandable).
  • Load memory: MMC plug-in, up to 4 MB.
  • Data retention on MMC: min. 10 years.
• Processing Times
  • Bit operations: 0.2 µs typ.
  • Word operations: 0.4 µs typ.
  • Fixed-point arithmetic: 5 µs typ.
  • Floating-point arithmetic: 6 µs typ.
• Digital Inputs
  • Number: 10 (8 usable for technological functions).
  • Input voltage: 24V DC; signal “0”: -3 to +5V; “1”: +15 to +30V.
  • Input delay: adjustable (0.1 / 0.3 / 3 / 15 ms).
  • Cable length: shielded 1000m (100m for tech functions).
• Digital Outputs
  • Number: 6 (2 high-speed outputs).
  • Output current: 500 mA per channel (max 0.6A).
  • Switching frequency: resistive load 100 Hz; pulse 2.5 kHz.
  • Short-circuit protection: electronic, typ. 1A threshold.
  • Total current per group: horizontal up to 2A (40°C).
• Counters & Timers
  • S7 counters: 128 (retentive adjustable).
  • S7 timers: 128 (time range 10 ms to 9990 s).
  • IEC counters/timers: unlimited (SFB).
• Address Area
  • I/O address: 1 KB each.
  • Process image: 128 bytes inputs/outputs.
  • Default addresses: DI 124.0-125.1; DO 124.0-124.5.
• Interfaces
  • MPI (RS485): 1 interface, cable length 50m.
  • No integrated Ethernet or RS422.
• Ambient Conditions
  • Horizontal installation up to 40°C: 10 inputs; up to 60°C: 5 inputs.
  • Vertical installation up to 40°C: 5 inputs.
  • Digital output derating above 40°C.
• Dimensions & Weight
  • Width: 80 mm, Height: 125 mm, Depth: 130 mm.
  • Weight: approx. 409 g.

Installation & Compatibility

• Requires front connector (1×40 pin) and Micro Memory Card.
• Programming package: STEP 7 V5.3 SP2 or higher with HW update.
• Supports up to 8 FM/CP modules (CP, PtP, LAN).
• No expansion racks; max 8 modules per rack.
• Clock synchronization via MPI (master/slave).
• Integrated software clock with max 15s/day deviation.

Maintenance & Diagnostics

• Maintenance-free backup via MMC (no battery).
• Operating hours counter: 1, range 0 to 2^31 hours.
• Diagnostic OBs: 4 asynchronous, 2 synchronous error OBs.
• Local data: 256 bytes per priority class.

Certifications & Compliance

• Input characteristic according to IEC 61131, type 1.
• Reverse polarity protection for inputs; outputs not protected.
• Designed for industrial environments (0-60°C operation).

Application Scenarios

• Small conveyor controls and packaging machines.
• Simple positioning and counting tasks.
• Replacement or upgrade of legacy S7-300 systems.
• Laboratory automation and test rigs.

Expert Review & Manager’s Insight

• Expert Review: The CPU 312C offers a cost-effective entry into S7-300. Its integrated I/O and fast counters reduce external hardware. For small projects, this PLC is robust and easy to program. The MMC backup ensures zero maintenance.
• Manager’s Insight: This model is a reliable workhorse for standard automation. The 32 KB memory fits small applications. Stock availability and 12-24h shipping make it a practical choice for urgent repairs or new setups.

Frequently Asked Questions (FAQ)

• What memory card is required?
  • Micro Memory Card (MMC), up to 4 MB.
• Can I expand the working memory?
  • No, the 32 KB working memory is fixed.
• Does the CPU support Ethernet?
  • No, only MPI (RS485). You can add a CP module.
• What is the maximum cable length for inputs?
  • Shielded: 1000m; unshielded: 600m.
• Is a battery required for data retention?
  • No, the MMC provides maintenance-free backup.
• How many digital outputs are high-speed?
  • 2 outputs can be used as high-speed (pulse) outputs.
• What is the typical inrush current?
  • 11 A typ, with I²t of 0.7 A²·s.
• Can I use this CPU in vertical mounting?
  • Yes, but derating applies: max 5 inputs and 1.5A output.

Selection Guide (经验性问答)

• Choose CPU 312C if: you need a compact CPU with integrated I/O and counters. Ideal for small machines and cost-sensitive projects.
• Consider larger CPUs if: your application needs more memory (>32KB) or more I/O points.
• For high-speed counting: the 2 fast counters (10 kHz) are sufficient for most incremental encoders.
• MMC size: 4 MB is recommended for larger programs and data logging.

Shipping & Warranty

• Shipping: 12-24 hours dispatch via FedEx, UPS, or DHL.
• Warranty: 12 months from date of purchase.
• All products are original Siemens spare parts.

Contact Information

• Email: sales@powergearx.com
• WhatsApp: +86 18030005825
• For technical support or bulk orders, please contact our team.

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