Reliance 805405‑1R

Technical Specifications

• AC Input Voltage: 120‑460 VAC, 50/60 Hz
• DC Output Voltage: 500 VDC maximum
• Rated Output Current: 15 A continuous field output
• Rectifier Topology: Non‑reversing full‑wave SCR bridge (four silicon‑controlled rectifiers)
• Isolation: Electrically isolated power cube construction
• Operating Temperature: 0 °C to +60 °C ambient for cabinet mounting
• Protection Devices: Built‑in AC input fuses, dv/dt suppression network, self‑firing clamping circuit

Functional Features

• Provides closed‑loop current‑regulated field excitation for shunt‑wound DC motors
• Isolated power cube separates high‑power field circuit from drive control logic
• dv/dt protection suppresses voltage transients generated by inductive motor field winding
• Internal fusing prevents catastrophic semiconductor failure under short‑circuit conditions
• Clamp circuit inhibits unintended SCR triggering from inductive kickback voltages

Application Scenarios

• Heavy‑industry DC variable‑speed drive systems
• Paper mills, metal rolling lines, extruders, large material‑handling DC motor drives
• Reliance AutoMax SD3100 and SF3000 drive cabinet retrofits and spare‑part replacement

Performance Parameters

• Regulation accuracy: ±3 % of set excitation current across full input‑voltage range
• SCR switching frequency synchronized to mains 50/60 Hz
• Overload withstand: 200 % rated current for short‑duration fault events

Material Composition

• Main substrate: Epoxy‑glass printed circuit board
• Power semiconductors: Silicon‑controlled rectifier thyristors
• Power connections: Copper bus terminals with tin plating
• Mechanical housing: Die‑cast aluminum alloy heat‑dissipating frame

Structural Characteristics

• Compact cube‑style plug‑in module for internal cabinet installation
• Direct plug‑on interface mating to SD3100 motherboard edge connector
• Integrated heat sink for SCR thermal dissipation without external separate cooling
• Terminal lugs for field‑winding high‑current wiring

Working Principle Mains AC input feeds full‑wave SCR bridge; drive control logic adjusts SCR firing angle to continuously modify average DC output voltage and current supplied to DC motor field winding. The internal current‑feedback loop stabilizes excitation current regardless of supply‑voltage fluctuation or field‑winding resistance drift from temperature rise.

Installation Requirements

• Mount inside ventilated industrial control cabinet, avoid direct exposure to dust, moisture and corrosive gas
• Comply with torque specification for high‑current field‑winding terminal connections
• Ensure adequate cabinet airflow to maintain module ambient below +60 °C
• Verify correct phase sequence of AC excitation input

Usage Notes

• Disconnect all AC and DC power before removal or insertion of module
• Do not operate without properly connected motor field winding; open‑circuit field condition can produce destructive high‑voltage transients
• Inspect internal fuses after any short‑circuit fault event
• Prevent mechanical shock during handling; SCR semiconductors are sensitive to physical impact