85014R is Reliance original SCR thyristor rectifier stack power module for FlexPak3000/MaxPak Plus DC drive system, matching with 846723T main control board,847216-R/S field excitation board and 847492-V auxiliary power board as complete drive power assembly. Original OEM production discontinued, supplied by new surplus stock and fully load-tested refurbished spare parts only; it undertakes AC-to-DC armature main power rectification and dynamic braking control for DC motor armature loop. R stands for standard factory original revision with integrated braking detection transistor circuit.

85014: Base part number of Reliance medium-power SCR rectifier stack assembly for DC drive armature power conversion.R: Standard factory revision configuration with built-in brake feedback detection circuit, counterpart upgraded version is 85014-RR with enhanced overcurrent protection layout.

Three-phase AC input 208/230/460VAC 50/60Hz; rated continuous armature DC output 230VDC, nominal rated output current 75ADC, short-time overload peak 110ADC within 60s. Integrated four parallel finned aluminum heat sinks with gap cooling structure, built-in high-power SCR thyristors, bleeder resistors and brake switch transistor components. Operating ambient temperature -10℃~+70℃, non-condensing humidity 5%~95%; overall dimension 242mm×165mm×98mm, net weight approx 2.35kg, withstand voltage between AC input and DC output 2800Vrms.

High-current bolt-type terminal studs for three-phase AC mains incoming and armature DC positive/negative output wiring; small screw terminal block for brake feedback signal hardwire connection to main control PCB. No digital bus or serial communication ports, all power and fault signals adopt discrete hardwired wiring only.

Receive phase-shift trigger pulse from 846723T main control board to realize three-phase full-wave SCR controlled rectification, convert industrial three-phase AC into adjustable variable DC voltage for DC motor armature speed regulation. Embedded dynamic braking transistor switch: when DC bus voltage exceeds 50VDC and brake current is zero, internal switching circuit closes for energy consumption braking; braking current detected via built-in sampling loop to output interlock signal to main control board for brake state monitoring. Integral passive bleeder resistor suppress DC bus overvoltage during motor coasting and power cut-off, internal component layout prevents instantaneous surge breakdown of power thyristors.

Specially configured for Reliance FlexPak3000 and MaxPak Plus series medium power DC drive cabinets, paired with existing series control & excitation spare parts combination; widely used as replacement spare for metallurgical wire drawing machine, papermaking drying roller, plastic calender, rubber mixer legacy DC drive power unit failure overhaul.

Cut off total cabinet AC power and keep power-off over 40 minutes to fully discharge high-voltage bus capacitor residual electricity before disassembly to avoid electric shock injury. Half-yearly maintenance: use dry low-pressure compressed air to blow dust between heat sink fins, strictly avoid cleaning liquid contacting SCR chip and high-power resistance components. After replacement installation, perform no-load trigger pulse inspection and DC output voltage calibration before full-load motor commissioning; store spare rectifier stack in ventilated anti-static warehouse to prevent dampness-induced SCR insulation degradation.