Product Details

The RELIANCE 5186518 current loop driver board is a discontinued inner loop control circuit card for Reliance Electric MaxPak Plus analog SCR DC drive rack systems, widely deployed in metallurgy, papermaking, rolling mill and other heavy-duty continuous production lines. It works with CVTH feedback board, regulator board and gate drive board, receiving current reference signal from the speed regulator, completing high-precision current closed-loop regulation and outputting control command to the SCR trigger unit, which realizes stable torque control and current limiting protection for DC motors.

This board adopts precision analog operational amplifier and pulse shaping circuit design. It compares the current reference value with the actual armature current feedback signal from the transductor board, executes PI adjustment for inner current loop, and limits the maximum output current to protect SCR power devices and motor windings. It integrates current gain adjustment potentiometer, fault detection and latch circuit, can capture overcurrent and current feedback loss faults and lock fault status for troubleshooting. It is equipped with surge absorption and noise filtering components to suppress SCR commutation interference and improve the stability of the inner current loop. It is a dedicated CLD current loop accessory for Reliance MaxPak Plus DC drive platform, cannot be directly replaced by other boards without matching rack slot, feedback signal polarity, current gain calibration and trigger phase debugging. Multiple current loop driver boards can be configured for independent control of multi-drive units.

It adopts rack plug-in installation structure with gold-plated edge connector and front panel adjustment potentiometer and status indicator. The PCB layout adopts low-noise and anti-vibration design, adapting to harsh industrial sites with large current switching noise and mechanical vibration. Users need to confirm matched MaxPak Plus rack motherboard, CVTH feedback board and wiring schematic before replacement. This legacy RELIANCE 5186518 board is mainly used for maintenance and retrofit of old MaxPak Plus DC drive systems. Current loop step response test, gain calibration and overcurrent protection threshold verification are required after installation. A conformal coated version is optional for high humidity and dusty industrial sites. This current loop driver board is widely used in Reliance MaxPak Plus drive renovation, inner current closed-loop regulation and heavy-duty constant torque speed regulation systems.

This current loop driver board obtains working power from the drive internal auxiliary power supply. The edge connector supports quick disassembly and replacement for convenient on-site maintenance and inspection. The optimal operating temperature range is 0°C to 55°C, storage temperature ranges from -40°C to +85°C, relative humidity 5% to 85% non-condensing. It complies with industrial shock, vibration and EMC standards and has CE certifications. It supports parameter backup for fast recovery after hardware replacement.

This RELIANCE 5186518 current loop driver board is widely applied in Reliance MaxPak Plus DC drive control systems. It undertakes inner current closed-loop regulation and current limiting protection. As a reliable spare part for Reliance legacy drive systems, the 5186518 retains original current regulation precision and anti-interference performance, helping customers reduce maintenance cost of old industrial automation equipment.