Siemens 6ES7312-5BE03-0AB0 CPU 312C Compact

SIEMENS 6ES7312-5BE03-0AB0 SIMATIC S7-300 CPU 312C Compact CPU

The SIEMENS 6ES7312-5BE03-0AB0, also cataloged as the 6ES7312-5BE03-0AB0 CPU 312C, operates as a compact central processing unit with integrated digital I/O and fast counters executing user logic within SIMATIC S7-300 platforms.

Hardware Specifications

Integrated I/O and Counter Functions

Unit weight is approximately 409 g with dimensions of 80 mm width, 125 mm height, and 130 mm depth. The CPU 312C integrates 10 digital inputs and 6 digital outputs with a 24 VDC power supply. Two fast counters operate at 10 kHz for technological functions. Bit operations execute in 0.2 us typical, word operations in 0.4 us, fixed point arithmetic in 5 us, and floating point arithmetic in 6 us. Work memory is 32 kbyte and is not expandable; load memory requires a micro memory card with a maximum of 4 Mbyte. Data retention on the MMC is guaranteed for a minimum of 10 years without battery. A total of 1024 blocks (DB, FC, FB) are supported with a maximum size of 16 kbyte per block. The integrated MPI RS 485 interface supports cable lengths up to 50 m without a repeater. Reverse polarity protection is provided on digital inputs but not on digital outputs. Digital outputs are short-circuit protected with a typical response threshold of 1 A and support switching frequencies up to 100 Hz with resistive load, 2.5 kHz for pulse outputs.

Frequently Asked Questions

Q: What is the weight and physical size of the 6ES7312-5BE03-0AB0?
A: Approximately 409 g, with dimensions of 80 mm width, 125 mm height, and 130 mm depth.

Q: What memory card does the CPU 312C require?
A: A micro memory card (MMC) is required. Maximum supported capacity is 4 Mbyte. The integrated 32 kbyte work memory is not expandable.

Q: How many fast counters does the CPU 312C support?
A: Two fast counters at 10 kHz for technological functions, with eight digital inputs usable for technological functions.

Field Installation Guidelines

Install the CPU in slot 2 of the S7-300 rail and secure the mounting screws. Verify 24 VDC supply polarity before energizing; digital inputs are reverse polarity protected, digital outputs are not. Insert a micro memory card before downloading the program. Confirm firmware version V2.6 matches the hardware update in STEP 7 V5.3 SP2 or higher. Route shielded encoder cables for technological functions to a maximum of 100 m; unshielded cables are not permitted for counter inputs. Verify MPI cable length does not exceed 50 m without a repeater. External power supply lines require a miniature circuit breaker type C at minimum 2 A or type B at minimum 4 A.