CUBE DOL – Direct On Line Motor Controller

The CUBE DOL is an intelligent motor controller designed and manufactured by SUBCOE for the protection, control, monitoring, and data acquisition of 3–phase AC motors. Its features make it suitable for a wide range of oil field and industrial applications such as Electrical Submersible Pumps (ESPs), Horizontal Pumping Systems (HPSs), and Progressive Cavity Pumps (PCPs).

The CUBE DOL monitors the 3–phase power supply feeding the motor through interface devices such as Potential Transformers (PTs), Advanced Voltage Monitor (AVM), Rogowski Coils (RCs), and Current Transformers (CTs). Reverse Rotation & Ground Fault Sensing features are incorporated to monitor the non powered rotation and cable fault. These features are obtained by applying advanced logic functions based on monitored changes in the controlled/protected system while maintaining a full host of memory and communications options inclusive of distributed networking and Internet remote control.

The CUBE DOL is also designed specifically to interface and operate with a range of pump company and independently manufactured Downhole Tools (DHTs), integrating the control and monitoring for ESP in one unit, thereby replacing proprietary surface panels.

In order to protect the system from damage (during fault) and/or to prevent operation until a fault is cleared, Alarm trip set points and action parameters are included. All Alarm trip set points have flexible time and restart options to allow the User to configure the controller according to the field conditions. The following are the conditions monitored and/or protected by The CUBE:

CUBE DOL Installed in Switchboard

CUBE DOL Installed in Switchboard

  • Current Underload and Overload
  • Undervoltage and Overvoltage
  • Current and Voltage imbalances
  • Reverse Rotation and Ground Fault
  • Under-Frequency and Over-Frequency (supply)
  • Supply Voltage
  • Active and Reactive Powers
  • Power Factor (PF)
  • Energy Acquisition
  • Internal Temperature

The communication features of The CUBE includes (1) front and rear USB ports, (2) RS485 master/slave ports, (3) on-board 4×20 character transflective display screen with LED backlights, and (4) intuitive full data entry keyboard (keypad) for fast and accurate entry of user data and programming set points.

The USB ports are multi-functional and can be used for downloading log files and trending information to a standard USB pen drive, firmware updates, and communication with external modules. Standard TCP/IP protocols are used for communication between The CUBE and PC devices. The CUBE is fully Modbus® compatible through a dedicated RS485 connection.

Container VFD/DOL Skid Control Room

Container VFD/DOL Skid Control Room

The standard features of The CUBE can be summarized as follows:

  • 4-line 20 digits high clarity transflective display and 24 key keypad,
  • On-board high intensity LED pilot lights for Auto start, Back spin, Alarm, On, and Off,
  • On-board control devices: AUTO, HAND, START, and STOP,
  • Zoom button to increase/decrease size of display digits,
  • 3 software selectable inputs for current measurement used with RCs or standard CTs with external Burden Resistors,
  • 3 voltage inputs – requires SUBCOE AVMs or 3 PTs with range of 0–5000:240VAC,
  • 100ms response time,
  • True Ground Fault protection,
  • True RMS voltage and current sensing,
  • Measurements of Voltages (VAC), Currents (A), Powers (kVA, kW, kVAR), PF, Frequency (Hz), and Energy (MVA∙h, MW∙h, MVAR∙h),
  • Reverse Rotation & Ground Fault monitoring,
  • 4 Digital Inputs and 4 Digital Outputs,
  • 4 Analog Inputs (software configurable for either 0–10V or 4–20mA),
  • 2 Analog Outputs (4–20mA),
  • 2 RS485 communication ports,
  • Modbus® RTU and Modbus® ASCII master/slave,
  • 2 USB communication ports,
  • Time stamped Data and Alarm log,
  • Time stamped Trending with 16 independent channels and user selectable step,
  • Standard on-board 256 MB memory with optional memory of up to 8GB,
  • Data Log and Trend download via USB memory drive or by LAN connection,
  • Cable LAN when optional USB-LAN converter is purchased, and
  • TCP/IP ready.