PWM-driven motors - servo motors, stepper motors, and variable frequency drives (VFD) - are a major source of electromagnetic interference (EMI) in equipment. They also cause a number of problems in equipment, including damage to the motor’s bearings due to leakage current causing electrical discharge machining (EDM) and damage to motor’s insulation.
New wide bandgap devices in the drives - SiC and GaN- based - have much faster rise and fall times of drive pulses - often 50 times faster. This greatly increases leakage current to ground, associated bearings damage, as well as overall EMI levels in the host equipment.
OnFILTER offers motor EMI filters for all three types of PWM motors - VFD, servo, and stepper motors. Patented technology employed in these filters substantially reduce high-frequency leakage currents in motors and in wiring, assisting in compliance with the requirements of IEC61800-3, IEC60034-17/-25 and NEMA MG 1-2016, as well as with NAMUR recommendations. The filters also reduce interfering high-frequency noise within the tool resulting from operation of PWM-driven motors.
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The motor filters greatly reduce high-frequency currents on equipment ground, as well as overall EMI in the tool, lowering risk of EOS and reducing errors in automated equipment and testers.
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No Mechanical Fitting, No Adjustments, No Wear, No Maintenance
OnFILTER' motion control filters have no mechanical coupling to the motors - all connections are electrical. Nothing to adjust, nothing to maintain. Their cost of ownership is zero.​
"We tested the servo filter on another system, this time with Kollmorgen motors. We saw another significant reduction in noise on our signal" (P.M.,U.K.)
We have all 3 filters installed on the machine. They seem to be working very well. It really suppresses the noise we were getting on the analog signals from the sensor (Director of Engineering, U.S.)
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No mechanical attachments
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No changes in software
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No adjustments
Click on the filter type suitable for your motor/drive for details:
Drive Pulse Edge Modification by a Filter

Ground Current Without the Filter

Ground Current With the Filter
