Delta HES Series Instructions For Use Manual page 106

Chapter 5 Methods of Anomaly Diagnosis
5-9 Electromagnetic/Induction Noise
If there exist noise sources around Hybrid Servo Controller, they will affect Hybrid Servo Controller
through radiation or the power lines, leading to malfunction of control loop and causing tripping or
even damage of Hybrid Servo Controller. One natural solution is to make Hybrid Servo Controller
immune to noise. However, it is not economical and the improvement is limited. It is best to resort to
methods that achieve improvements outside Hybrid Servo Controller.
1. Add surge killer on the relay or contact to suppress switching surge between ON/OFF.
2. Shorten the wiring length of the control circuit or serial circuit and separate from the main
circuit wiring.
3. Comply with the wiring regulation for those shielded wire and use isolation amplifier for
long wire.
4. The ground terminal of Hybrid Servo Controller must be connected to ground by
following the associated regulations. It must have its own ground connection and cannot
share with electrical welder and other power equipments.
5. Insert noise filter to the input terminal of Hybrid Servo Controller to prevent the noise
entering from the power lines.
In a word, three-level solutions for electromagnetic noise are "no product", "no spread" and "no
receive".
HES Series
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