ABB / Baldor / Reliance ZD18H403-E AC Vector Controller

The ZD18H403-E is a Series 18H AC Flux Vector Controller engineered for precise motor speed and torque control in industrial drive applications. This 460 VAC, three-phase unit delivers 3 HP / 2.2 kW at constant torque or 5 HP / 3.7 kW at variable torque, with maximum output frequency to 500 Hz. The controller employs advanced vector control algorithms and integrates dynamic braking for rapid load deceleration without regenerative or DC injection capability.

Technical Specifications

• Input: 460 VAC, 50/60 Hz, three-phase


• Output Current: 5.2 A / 5 A (constant torque); 10 A / 8.2 A (variable torque)


• Maximum Output Frequency: 500 Hz


• Horsepower: 3 HP / 2.2 kW (constant torque); 5 HP / 3.7 kW (variable torque)


• Dimensions: 12" H × 7.7" W × 7.1" D; Weight: 18 LB (net) / 23 LB (shipped)


• Enclosure: NEMA 1 standard; NEMA 4X available for washdown duty


• Operating Temperature: 0°C to 40°C


• Cooling: Forced air

Key Features

• Dynamic braking for load holding and deceleration control


• Adjustable current limit with line-to-line and line-to-ground fault protection


• Motor overspeed, overload, and over-temperature protection with linear heat sink thermal monitoring


• Isolated control circuitry and selectable automatic restart at momentary power loss


• Keypad operator interface with digital display for fault diagnosis


• UL and CUL agency approvals

Interfaces and Options The controller supports optional communication and feedback modules including RS232, RS422/RS485, analog relay output, DC tachometer interface, high-resolution analog input, isolated encoder input, resolver input, and master/pulse/follower configurations.

Typical Applications Suitable for variable torque, constant torque, and constant horsepower loads in new installations, retrofit replacements, and OEM integration. Designed for AC vector duty motors in demanding industrial environments. Note: This model is discontinued by the manufacturer.