Schneider Altivar 312 ATV312 Replacement

Overview

The Schneider Electric Altivar 312 (ATV312) variable frequency drive (VFD) was a cornerstone of industrial machine automation for over a decade. Designed for simple commercial and industrial machines, its high starting torque, robust communication options, and compact design made it a highly popular solution for conveyors, packaging lines, pumps, and fans.

However, as industrial automation migrates toward smarter, highly integrated, and safety-focused architectures, the ATV312 has entered the final stages of its lifecycle. For facilities operating with legacy machinery, planning an upgrade or sourcing replacement parts for the ATV312 is critical to preventing unplanned downtime. This guide details the technical specifications of the legacy ATV312 series, presents the factory-recommended replacement pathways—specifically the Altivar Machine ATV320—and outlines the precise mechanical, electrical, and parameter migration steps required for a successful retrofit.

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Legacy Product Information

The Altivar 312 was launched as the direct successor to the Altivar 31 (ATV31). It covered a power range from 0.18 kW (0.25 HP) up to 15 kW (20 HP) with multiple input voltage options.

Part Number Breakdown (Catalog Schema)

A typical ATV312 part number follows this structure (e.g., ATV312HU15N4):

• ATV312: Drive Series
• H: Product designation (IP20/Open type)
• U15: Power rating (e.g., U15 = 1.5 kW, 075 = 0.75 kW, D11 = 11 kW)
• N4: Voltage code
  • M2: 200…240 V single-phase
  • M3: 200…240 V three-phase
  • N4: 380…500 V three-phase
  • S6: 525…600 V three-phase

Key Legacy Specifications:

• Control Method: Sensorless vector control (voltage/frequency 2 points, 5 points, or energy saving ratio)
• Overload Capacity: 150% of nominal drive current for 60 seconds
• Integrated Communications: Modbus RTU and CANopen (RJ45 port)
• Expansion Communication Cards: CANopen Daisy Chain, DeviceNet, PROFIBUS DP, Modbus TCP/IP, and EtherNet/IP
• Analog/Digital I/O: 3 Analog Inputs, 1 Analog Output, 6 Digital Inputs (sink/source), 2 Relay Outputs
• Lifecycle Status: Obsolete. Official factory production ended in 2016, with commercial support and service channels phased out globally.

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Recommended Replacements

Schneider Electric designated the Altivar Machine ATV320 as the primary functional replacement for the ATV312. In certain cost-sensitive or complex configurations, alternative families are also applicable.

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Compatibility Considerations

When migrating from an ATV312 to an ATV320, several physical, electrical, and control architecture factors must be evaluated:

1. Physical Footprint and Form Factors

The ATV320 is unique because it is available in two designs:

• ATV320...C (Compact): This version matches the depth and general width profile of the old Altivar 312. If you are retrofitting into a tight electrical panel where depth is restricted, the Compact form factor is usually the mandatory choice.
• ATV320...B (Book): This design is slim and tall, ideal for side-by-side mounting in new panel builds to conserve horizontal space. If replacing an ATV312 with an ATV320 Book format, layout and mounting hole modifications will be required.

2. Control Terminals and Wiring

• ATV312: Used pluggable screw clamp terminals.
• ATV320: Features spring-clamp (tension-clamp) terminals.
• I/O Count: While the core digital inputs (DI1 to DI6) and analog inputs (AI1 to AI3) are functionally equivalent, the spacing and layout on the physical block differ. Ensure wire tags are clearly labeled before disconnecting the old drive terminal blocks.

3. Integrated Safety Functions

The ATV312 had no onboard functional safety inputs. Standard machine integration required upstream safety contactors. The ATV320 includes an integrated Safe Torque Off (STO) function (SIL3 / PL e compliant). To use this configuration, modify your e-stop loop to wire directly to the STO terminals on the ATV320, eliminating the need for bulky isolation contactors.

4. Communication Networks

The ATV312 utilized optional communication cassette cards that mounted on the front face of the drive. The ATV320 supports these protocols using modern cassette adapters or embedded network interfaces (EtherNet/IP, Modbus TCP, EtherCAT, PROFINET, Profibus DP, DeviceNet, CANopen). Network addressing and master PLC configuration files (EDS/GSDML) must be updated to reference the new ATV320 profile.

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Upgrade Benefits

Upgrading to a modern variable speed drive yields significant operational advantages:

• Enhanced safety compliance: Integrated safety features reduce required panel space and component counts.
• Embedded logic: The ATV320 features ATV Logic (built-in PLC capability), allowing basic control programming directly inside the drive using SoMove software.
• Expanded Motor Type Compatibility: ATV312 only supported asynchronous (induction) motors. The ATV320 supports both induction and permanent magnet synchronous motors (PMSM), which provide exceptional energy efficiency under varying loads.
• Modern software tools: Configuration is simplified using Schneider’s current SoMove commissioning software, replacing legacy PowerSuite.

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Common Migration Challenges

• Parameter File Conversion: Direct transfer of an ATV312 parameter file backup to an ATV320 via a loader tool is not supported. The parameter profiles must be converted or manually remapped.
• RJ45 Pinout Configuration: While both series support Modbus/CANopen over RJ45, the surrounding hardware shielding and daisy-chain topology layouts can vary between the physical dimensions of the modules.
• Current Derating: In high ambient temperature environments (>50°C), check the catalog specifications for the ATV320, as derating factors differ slightly from the legacy ATV312 models.

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Step-by-Step Replacement Procedure

Follow these steps to safely replace an ATV312 drive with an ATV320:

Step 1: Record Parameters and Configurations

Before power-down, extract the parameter values of the existing ATV312:

1. Connect to the ATV312 using SoMove software with a USB-to-RJ45 Modbus cable (VW3A8106).
2. Save the configuration as a .pseg or .psx project file on your computer.
3. Alternatively, if using the local 7-segment HMI display, manually write down modified parameters in the reference menu (SUP- and FUn- menus).

Step 2: Power Down and LOTO

1. Disconnect the main AC power utility feed feeding the branch circuit.
2. Execute standard Lockout/Tagout (LOTO) protocols.
3. Test all input terminal phases (L1, L2, L3) with a calibrated digital multimeter to verify zero voltage.
4. Important: Wait a minimum of 15 minutes for the internal DC bus capacitors to fully discharge. Confirm DC bus voltage is < 50V across terminals (PA/+ and PC/-) before handling wiring.

Step 3: Disconnect Terminal Control and Power Wiring

1. Label all control cables connected to standard digital and analog inputs.
2. Carefully unplug the control terminal blocks or unscrew control terminal leads.
3. Remove power cables from the input line terminals (L1, L2, L3), motor output terminals (U, V, W), and braking resistor terminals (if utilized).

Step 4: Physical Demounting and Mechanical Installation

1. Unscrew the mounting bracket bolts securing the ATV312 to the enclosure subpanel. Remove the legacy drive.
2. Compare mounting dimensions. If utilizing the ATV320 Compact, align with the existing mounting holes. If utilizing the ATV320 Book, mark and drill new mounting holes using the dimension template provided in the ATV320 installation manual.
3. Secure the new ATV320 drive to the subpanel. Ensure appropriate clearance (at least 50mm above and below) for optimal heat dissipation.

Step 5: Power and Control Re-wiring

1. Connect ground lines to the PE grounding terminals.
2. Wire the motor cables to output terminals U, V, and W.
3. Wire the incoming utility lines to input terminals L1, L2, and L3.
4. Map the wire terminations to the new spring terminals of the ATV320:
   • ATV312 LI1...LI6 maps directly to ATV320 DI1...DI6.
   • ATV312 +24V maps to ATV320 +24V.
   • ATV312 AI1/AI2/AI3 maps to ATV320 AI1/AI2/AI3 (verify current/voltage switch configurations on the analog cards).
5. If using standard 2-wire control, bridge the default emergency stops or wire into the designated Safe Torque Off (STO) terminals (STOA and STOB supplied by +24V).

Step 6: Parameter Commissioning

1. Open the saved ATV312 SoMove project. Use SoMove’s device conversion/migration wizard. Select the target drive type corresponding to the specific new ATV320 part number. The software will map matching configuration parameters.
2. Download the newly created .psx file into the ATV320 using the same interface cable.
3. Run a physical test to check critical motor nameplate parameters:
   • Nominal Motor Voltage (UnS)
   • Nominal Motor Frequency (FrS)
   • Nominal Motor Current (nCr)
   • Nominal Motor Speed (nSp)
4. Perform an Auto-tuning (tUn) sequence with the motor connected but uncoupled from the load, if mechanical configuration permits, to optimize vector performance.
5. Verify motor rotation direction at slow speed before resuming normal production.

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Frequently Asked Questions

Q: Can I use the old ATV312 remote keypad on the new ATV320?

No. The remote display terminals have different internal software profiles. For remote mounting on an ATV320 enclosure door, you must use the modern graphic display terminal part number VW3A1111 or the simpler numerical display terminal VW3A1104.

Q: Is there a fast mechanical adapter kit available for mounting?

Yes. Schneider Electric provides retrofit mounting plates for specific frame size transitions, enabling you to mount an ATV320 Book or Compact drive directly using the exact footprint left behind by the ATV312 without redrilling holes.

Q: Why is my new ATV320 showing an "STO" fault immediately upon power-up?

By default, the ATV320 expects active safety inputs on terminals STOA and STOB. If you do not require functional safety and are replacing an ATV312 which did not use it, you must install jumper wires connecting +24V to both STOA and STOB to bypass the safety check.

Q: Can I commission the ATV320 without a PC using a standard smartphone?

Yes. The ATV320 supports the optional Bluetooth module or connection via Schneider's mobile commissioning tools, providing an alternative to laptop-based configuration.

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Related Products & Families

• Altivar Machine ATV320 VFDs: The primary modern replacement series.
• Altivar 12 VFDs: Suited for entry-level single-phase machinery replacement.
• Altivar 340 VFDs: Suited for high-performance and Ethernet-dependent applications.
• SoMove Software Suite: The universal programming software used for commissioning.

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Need Help?

If you are planning an upgrade or need immediate replacements for your obsolete Schneider Altivar 312 VFDs, Palm Parts Solution can support your operations. We supply a comprehensive inventory of new, high-quality refurbished, and hard-to-find surplus legacy components—all backed by our comprehensive warranty. Contact Palm Parts Solution today to source a replacement unit or get technical guidance on your upgrade path.