/Products/VFD's & Soft Starters/KB Electronics/KBMG/8831 KB Electronics Ultracompact Regenerative Drive, 115/230VAC, 0.75/1.5HP
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Product ID: KB8831

8831 KB Electronics Ultracompact Regenerative Drive, 115/230VAC, 0.75/1.5HP

MFG: KB Electronics, Inc
MFG Part Number: 8831

Available Stock: 10
Selected accessories will also be added to cart
$164.50 / Each
KBMG-212D, IP20, Full Wave, 0-90VDC/0-180VDC 8 Amps Output
Select any of the accessories below to purchase them with this inventory item:


The KBMG are ultracompact, full-wave regenerative drives capable of operating DC PM or Shunt motors in a bidirectional mode. Its (4) quadrant operation provides forward and reverse torque in both speed directions. This allows the control to maintain constant speed with overhauling loads and provides rapid reversing and controlled braking. Because of its excellent controllability and response time, the KBMG can replace servos in many applications. The control is factory set for armature feedback, which provides up to 1% load regulation over a motor base speed of 50:1. Tachgenerator feedback is also provided for superior load regulation if required. A simple jumper setting converts the KBMG to a torque control. In this mode, motor torque rather than motor speed is controlled.

An important feature of the drive is the factory-calibrated, built-in, selectable motor current jumper. It eliminates the need to recalibrate IR Comp and Current Limit for most applications.

The control contains an Enable function that can be used to start and stop the motor electronically via a contact closure. Through a jumper selection, the motor can be controlled to rapidly “regenerate to stop” or to “coast to stop.”

KB’s exclusive Auto Inhibit® circuit provides safe, smooth starting even during rapid cycling of the AC line. The Overspeed Protect Circuit prevents failure of the power bridge in extreme overhauling conditions. Reliability of the KBMG is further enhanced with the use of a high speed current limit circuit and MOV transient protection. LED’s, which can be used for diagnostics, are provided for power on and motor overload. A rugged extruded aluminum heat sink ensures enhanced heat transfer, which provides a higher control rating while maintaining cooler running SCR’s. The KBMG contains a finger-safe cover to meet the IP-20 Standard.

Power connections to the KBMG are made via quick connect terminals and signal input connections are made via a removable barrier terminal block. A 5k remote potentiometer and full operating instructions are supplied.


Manufacturer KB Electronics (Nidec)
Part Number 8831
Model Number KBMG-212D
AC Line Voltage 115/208-230 VAC +/-10%
Single Phase
Motor Voltage 0 to +/-90VDC @ 115VAC Line
0 to +/-180VDC @ 230VAC Line
Maximum Rating Without Heat Sink 12.0 AMP AC Line Current
8.0 Amps DC Load Current
0.75HP (0.6kW) @ 115VAC Line
1.5HP (1.1kW) @ 208/230VAC Line
Maximum Rating with Auxiliary Heat Sink 16.0 AMP AC Line Current
11.0 Amps DC Load Current
1.0HP (0.75kW) @ 115VAC Line
2.0HP (1.5kW) @ 208/230VAC Line


AC Line Input Voltage 115 or 208/230VAC +/-10%
AC Line Frequency 50/60Hz
Armature Voltage Range 0 to +/-90VDC @ 115VAC Line
0 to +/-90VDC / 0 to +/-180VDC @ 230VAC Line
Field Voltage 100/50VDC @ 115VAC Line
200/100VDC @ 230VAC Line
Maximum Load Capacity 150% for 2 Minutes
Ambient Temperature Operating Range 0 to 50°C
Speed Range 50:1 Ratio
Armature Feedback Load Regulation +/-1% of Base Speed
Tach-Generator Feedback Load Regulation +/-1% of Base Speed
AC Line Regulation +/-1% of Set Speed
Current Ranges 1.7 Amps DC
2.5 Amps DC
5.0 Amps DC
7.5 Amps DC
10 Amps DC
Forward/Reverse Acceleration Range 0.1 to 15 Seconds
Dead Band Range 0 to +/-5% of Base Speed
Max Speed Trimpot Range 55 to 110% of Base Speed
IR Compensation Range 0 to 20VDC Full Load @ 115VAC Line
0 to 40VDC Full Load @ 230VAC Line
Forward/Reverse Range 0 to 175% Range Setting
Voltage Following Input Range 0 to +/-10 VDC
0 to +/-15 VDC
Voltage Following Linearity +/-0.5% Base Speed



4 Quadrant


SCR Bidirectional Variable Speed and Torque Control for PM and DC Shunt Motors

Jumper Selectable Features:

  • Operation Mode: Speed, Torque
  • AC Line Voltage (VAC – 50/60 Hz): 115, 230
  • DC Armature Voltage (VDC): 90, 180
  • Tach-generator Voltage (VDC/1000 RPM): 7, 50
  • DC Current Output Ranges (ADC): (1.7 – 10)
  • Analog Input Voltage (VDC): 0 to ±10, 0 to ±15
  • Enable: Coast to Stop (CTS), Regenerate to Stop (RTS)

Trimpot Adjustments:

  • Dead Band (DB)
  • Response (RESP)
  • IR Compensation (IR)
  • Forward Current Limit (FCL)
  • Reverse Current Limit (RCL)
  • Maximum Speed (MAX)
  • Forward Acceleration (FACC)
  • Reverse Acceleration (RACC)


  • Power On (PWR ON)
  • Overload (OL)


  • Conveyors
  • Indexers
  • Feeders
  • Positioners
  • Textile Equipment
  • Packaging Machinery
  • Web Control
  • Converting Machinery

Drive Accessories

Auxiliary Heat Sink (Part No. 9861)

SIMG Bipolar Signal Isolator (Part No. 8832)

Multi Speed Board (Part No. 8833)

DIN Rail Mounting Kit (Part No. 9995)