BLSD-20Modbus - BLDC controller  for 3-phase DC brushless motors

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BLSD‑20Modbus - brushless motor controller with RS‑485 Modbus

BLSD‑20Modbus is a brushless dc motor controller for three-phase motors with Hall sensors. This intellegent controller can be pre-programmed according to the system demands and work as a standalone drive, can operate as a slave in RS-485 network or operate as a simple DC brushless motor controller for speed control. BLSD-20Modbus provides position control based on Hall sensors information, speed regulation, current limiting function. Thanks to the current limiting function, BLSD-20Modbus protects the motor from overloads. Maximum rated current can be limited according to the brushess motor model (up to 20A). This controller is used for DC brushless motors 24V, 36V, 48V with rated power up to 1000W.

BLSD-20Modbus can be used as a standalone unit or can be controlled by a master device in RS-485 network. The controller is programmable, the programming software is easy to use and free of charge.

The main parameters of brushless controller BLSD‑20Modbus

  • Power supply: 24 ‑ 48 VDC
  • Rated current: 20 Amp
  • Max. current: 80 Amp
  • Regulation of peak power
  • Communication interface: RS‑485, Modbus – ASCII or RTU

BLSD-20Modbus features and capabilities

  • the unit can be controlled via the RS-485 interface using the Modbus RTU or ASCII protocol or by external signals supplied to the controller inputs;
  • motor rotation speed can be set via Modbus or external analog signal;
  • motor position can be set via Modbus;
  • setting the values ​​of acceleration and deceleration;
  • setting the maximum value of the motor current (motor overload protection);
  • drawing up a user control program, starting the program by command via Modbus or automatically when the drive is powered up;
  • programming inputs IN1 and IN2, which can also be used as START / STOP and REVERSE / DIRECTION signals;
  • selection of the logic of the input signals IN1 and IN2 (START / STOP and REVERS) - triggering on the edge or signal level;
  • positioning to a given coordinate or displacement by a given value according to the Hall sensors.

Speed control:

BLSD-20Modbus can be used as a brushless motor speed controller for the most types of industrial systems. Speed control and stabilization is based on information from Hall sensors. The value of actual motor speed is avaluable through RS-485 Modbus. Target speed can be set in several ways:

  • External analog signal (0 .. + 5 V or potentiometer)
  • Modbus commands
  • Pre-set parameter value
  • As an instruction inside the user program (if the controller operates according to the pre-programmed algorithm - user program)

Position control:

BLSD-20Modbus provides possibility to control the position of the 3-phase DC motor, position holding function is also available. Brushless motor position control is based on information about the motor poles number and internal Hall sensors counter. The value of actual position is avaluable through RS-485 Modbus. The position can be set as a coordinate or displacement, the target value can be set:

  • As a Modbus commands from PC or PLC
  • As a pre-set parameter value
  • As an instruction inside the user program (if the controller operates according to the pre-programmed algorithm - user program)

BLSD-20Modbus programming

The most simple command system allows you to compose brushless motor control algorithms as a sequence of executable instructions. The controller allows loops, wait timers, use conditional and unconditional (relative and absolute) jumps, create and use subroutines. The maximum program length is 1024 instructions.

Dimensions of controller BLSD‑20Modbus:

dimensions of controller BLSD-20Modbus for BLDC 3-phase DC brushless motors