News Article

Oct 10 2013

Saminco’s 4160V VFD Installed on Mine Slope Belt


Saminco recently installed a 4160 Volt Variable Frequency Drive System in West Virginia on a mines slope belt, replacing an antiquated fluid coupling system with continual maintenance issues.  Only  two days were required to completely switch out and return to full operations with a single 1750HP VFD and all associated switchgear needed to operate three separate motors. 

With more efficient operations and lower current requirements than the older system, the new Saminco VFD System can also be remotely monitored and controlled via web and cell based devices.

The Saminco 4160V VFD system offers the following features and benefits:

 A Three Cables In, Three Cables Out Feature incorporates a standard pad-lockable input fused disconnect switch with a vacuum contactor and interlocked doors and eliminates the need for a secondary power source, improving the safety of system personnel.

A Small Footprint allows the drive to be easily retrofitted and paired with medium voltage motors without upgrading the motor insulation. Additionally, it eliminates the need for an output transformer and allows for the use of standard bearings without grounding or isolation means.

 A 24-Pulse Isolation Transformer provides phase-shift cancellation capabilities, eliminating issues concerning harmonic injections into bus-fed equipment. As a result, the MV300 resembles a linear load on the incoming AC line.

 Five-Level PWM Output closely simulates a true sine wave by employing several layers of switching devices to provide a smooth output waveform to the motor, virtually eliminating motor failures caused by insulation stress and long lead-length issues.

 A Versatile Control Interface offers eight digital inputs, six digital outputs, two analog inputs, and eight analog outputs as standard. Each of these input/outputs can be programmed to a variety of different functions for ultimate flexibility.

 A Plain-English LCD Electronic Operator Interface (EOI) allows for quick, user-friendly programming. Faults are logged containing date and time stamps.

 Windows®-Based WiTool Software is designed to offer a full range of programming and monitoring tools. Operating data can be captured with the snapshot feature and up to 12 drive signals can be trended. In addition, the WiTool offers trace-back data for detailed fault analysis.


Figure 1: 1750HP, 4160V, VFD System4160V_Switchgear

Figure 2: 4160V, Switchgear containing the following:

Visible Disconnect
Vacuum Contactor
Panel View Plus 400 PLC
GE Multilin 369
High Voltage Ground Monitor
Ground Fault Relay


Figure 3: Slope Belt Motors


Figure 4: Slope Belt