The LTi SO84.004 is a three-phase servo drive controller from the ServoOne family, designed for single-axis systems with air cooling. Operating on 3 x 230V to 3 x 480V AC mains, this BG1 sized unit delivers 4A continuous current and 8A peak current, making it an excellent choice for compact industrial automation applications requiring robust performance and flexible voltage compatibility.
Wide three-phase mains range: 3 x 230V / 400V / 460V / 480V ±10%
Rated output current: 4 A (continuous), peak 8 A (0-5 Hz)
Compact BG1 housing: width 58.5 mm, height 295 mm, depth 224 mm, weight 3.4 kg
Air cooling – suitable for standard control cabinet installation
Integrated mains filter (C2/C3 compliance per EN 61800-3)
Integrated brake chopper with external braking resistor capability (minimum 90 Ω)
Safe Torque Off (STO) function for machine safety
Dual encoder interfaces: resolver (X6) and high-resolution (X7 for SinCos, EnDat, HIPERFACE)
Mains voltage: 3 x 230V / 400V / 460V / 480V AC ±10%
Mains frequency: 50/60 Hz ±10%
Rated current (IN): 4 A (at 400V, 8 kHz switching frequency)
Peak current (0-5 Hz): 8 A (for intermittent operation)
Switching frequency: 4 kHz, 8 kHz, 12 kHz, 16 kHz (selectable)
Output voltage: 3-phase up to mains input
Rotating field frequency: 0 ... 400 Hz
Connected load (with mains choke): 2.8 kVA / 4.0 kVA (without choke)
Power loss at IN: 65 W (typical, at 8 kHz)
DC link capacitance: 470 μF
Brake chopper switch-on threshold: 390V DC (for 3x230V) / 650V DC (for 3x400V) / 745V (460V) / 765V (480V)
Minimum external braking resistor: 90 Ω
Continuous braking power (external): 230 W
Peak braking power (external): 6.25 kW
Control supply: 24V DC ±20%, max. starting current 6 A, continuous 2 A
Digital inputs: 6 (including two high-speed touch-probe inputs)
Digital outputs: 3 (high-side, 50 mA each)
Analog inputs: 2 differential (±10V, 12-bit)
Relay output: 1 changeover (30V DC / 1A)
Motor brake output: 24V DC, up to 2 A (short-circuit proof)
Encoder resolver input: X6 (9-pin D-sub)
High-resolution encoder input: X7 (15-pin D-sub) supports SinCos, EnDat, HIPERFACE, SSI
Communication: USB 1.1, Ethernet 10/100 BASE-T (service & diagnostics)
Degree of protection: IP20 (terminals IP00)
Cooling: Air cooling (internal fan for BG1)
Ambient temperature: -10°C to +45°C (4 kHz), derating above 40°C for higher switching frequencies
Storage temperature: -25°C to +55°C
Pollution severity: 2 (EN 60664-1)
Mounting: Vertical, control cabinet min. IP4x (IP54 for STO)
Dimensions (W x H x D): 58.5 x 295 x 224 mm
Weight: 3.4 kg

The SO84.004 must be mounted vertically on a conductive, grounded mounting plate. Maintain minimum distances of 40 mm above and below the device for proper airflow. Use shielded motor and signal cables with double copper braiding. Connect the PE conductor with a cross-section of at least 10 mm² copper (if mains cable<10 mm²). Always connect the 24V control supply first (terminals X9/X10) before applying AC mains to X11. For EMC compliance, keep motor cable lengths ≤10 m for full rated current. An external mains choke is recommended for hostile industrial environments.
Commissioning the SO84.004 is straightforward using LTi's DriveManager 5 software via USB or Ethernet. After powering the 24V control supply, the 7-segment display shows "00" during initialization and then "51". Load the motor dataset for LTi LSH/LST synchronous servo motors or configure parameters manually. Enable the power stage by setting the STO inputs (ISDSH and ENPO) to +24V. The drive can then be controlled via analog setpoint, fieldbus (optional), or the manual operation dialog.
The two-digit 7-segment display provides real-time device status: "5" = ready, "3" = switched on, "4" = motor energized, "6" = quick stop. In case of an error, the display alternates between "Er" and an error number (e.g., 05 for overcurrent) followed by an error location code. The DriveManager 5 software offers detailed error history and live monitoring of all critical parameters.
Typical applications include small conveyor systems, winding machines, test stands, robotics auxiliary axes, and any single-axis positioning requiring precise speed and torque control. The wide voltage range (230V to 480V) makes the SO84.004 suitable for global deployment without hardware changes.
The LTi SO84.004 conforms to low voltage directive 2006/95/EC, EMC directive 2004/108/EC, and EN 61800-5-1. It meets EN 61800-3 requirements for second environment (C3) and first environment (C2) when installed with appropriate mains filter and cabling. UL approval conditions are specified for BG1 devices (max. 5kA short-circuit rating, copper 75°C cables).
Each SO84.004 unit includes the drive controller, terminal accessory pack, product DVD, and installation instructions. Optional accessories include external braking resistors, mains chokes, and MMC cards for parameter copying. For fieldbus integration, option 1 slots can accept EtherCAT, SERCOS, or other communication modules.
The LTi SO84.004 combines a small footprint with powerful three-phase servo control, making it a versatile choice for machine builders and system integrators. Its robust design, extensive I/O, and safety features ensure reliable operation in demanding industrial environments.



