JSP Panel

Control Modes 

• Velocity, Torque 

Command Interface 

• ±10V velocity/torque command 

• PWM velocity/torque command 

Communications 

• RS232 

Feedback 

• Back-EMF (velocity mode) 

I/O - Digital 

• 5 inputs, 1 output 

Dimensions: mm [in] 

• 130 x 82 x 31 [5.1 x 3.2 x 1.2]

DESCRIPTION 

The Junus™ digital servoamplifier puts 100% digital control of DC 

brush motors in a panel-mounting package with power options to 

±15 Adc continuous and ±30 Adc peak from +20 Vdc to +180 Vdc 

DC power supplies.

Torque mode operation works with popular position-loop controllers

that use PID filters to close a position-loop. Sensorless velocity

control works with position loop controllers that only output a 

position-error signal such as PLC’s. 

Set-up is fast and automated by CME 2™ software operating under 

Windows®. 

CME 2™ communicates with Junus™ through an RS-232 link for 

complete amplifier setup. Auto-tuning algorithms in CME 2™ 

slash set up times for fast system commissioning by automating 

current and velocity-loop tuning. A powerful oscilloscope and 

signal generator display amplifier performance for fine tuning 

thereafter. 

Amplifier control parameters are saved in non-volatile flash memory. 

OEM’s can inventory one part, and configure amplifiers on-site to 

each axis in a machine. 

Current-loop sampling at 20 kHz yields high-bandwidth with full

adjustability. The velocity loop is sampled at 4 kHz for wide velocity 

bandwidths. 

Carrier-cancellation modulation all but eliminates motor ripple 

current and dissipation at a standstill, and provides excellent 

crossover characteristics for voice-coil applications that demand low 

distortion around zero. PWM ripple is at 40 kHz, further minimizing 

losses in low-inductance motors.

Sensorless velocity control regulates motor back-EMF and 

compensates for changes in load that would cause a speed change 

with simple voltage controls. Amplifier output voltage is increased to 

offset the internal I*R voltage drops, keeping back-emf constant. 

All amplifier circuits are DC coupled and operate from unregulated 

transformer-isolated DC power supplies, or regulated switching 

power supplies. 

The panel-mount package is compatible with the mounting footprint 

of Copley’s 4xx series analog DC brush-motor amplifiers, offering

an easy upgrade to 100% digital control.