Frequently Asked Questions

Harmonics and Harmonic Mitigating Transformers (HMT’s) Questions and Answers

This document has been written to provide answers to the more frequently asked questions we have received regarding harmonics and the Harmonic Mitigating Transformer technology used to address them. This information will be of interest to both those experienced in harmonic mitigation techniques and those new to the problem of harmonics.

1. What are non-linear loads and why are they a concern today?
2. Do different types of non-linear loads generate different harmonics?
3. Why do non-linear loads have low power factors and why is it important to have a high power factor?
4. What is an SMPS and how does it generate harmonics?
5. Can’t equipment manufacturers design their products to be free of harmonics?
6. What problems do non-linear loads and harmonics create?
7. Why do 3rd harmonic currents overload neutral conductors?
8. How do non-linear loads create current and voltage harmonics?
9. What ill effects do the harmonics created by computer power supplies have on themselves?
10. How do harmonics increase power losses and overheat transformers?
11. What are zero sequence harmonic filters and how do they reduce 3rd harmonic and prevent neutral conductor overheating?
12. What is an Harmonic Mitigating Transformer and how is it different than a K-rated Transformer?
13. How do Harmonic Mitigating Transformers reduce voltage distortion?
14. How do Harmonic Mitigating Transformers save energy?
15. What constitutes an EPA Energy Star Transformer and is it important when supplying non-linear loads?
16. How reliable are transformer energy efficiency tests (including Independent 3rd Party) under non-linear loading?
17. Am I not safe from harmonics if I use K-Rated transformers and oversized neutrals?
18. Are there standards that can help in addressing harmonics?
19. Can neutral currents, such as the 3rd harmonic, be reduced by the use of 3rd Harmonic Blocking Filters?

LINEATOR™ Advanced Universal Harmonic Filter for VFD’s Questions and Answers

This document has been written to provide answers to the more frequently asked questions we have received regarding the application of the LINEATOR™ Advanced Universal Harmonic Filter on Variable Frequency Drives (VFD’s). This information will be of interest to both those experienced in treatment of harmonics generated by VFD’s and those new to the problem of harmonics.

1. What are non-linear loads and why are they a concern today?
2. Do different types of non-linear loads generate different harmonics?
3. Why do non-linear loads have low power factors and why is it important to have a high power factor?
4. What is a Variable Frequency Drive and how does it generate harmonics?
5. What problems do non-linear loads and harmonics create?
6. How do non-linear loads create current and voltage harmonics?
7. What ill effects do the harmonics created by VFD’s have on themselves?
8. What is IEEE Std 519 and how does it apply to VFD installations?
9. What is the LINEATOR™ AUHF and how does it treat VFD harmonics?
10. How is the LINEATOR™ different than other forms of passive harmonic filters?
11. What other forms of harmonic treatment are available for VFD’s?
12. How does the LINEATOR™ compare to a 12-Pulse or 18-Pulse VFD?
13. Is the LINEATOR™ compatible with all VFD’s?
14. Is the LINEATOR™ suitable for generator applications?
15. What if my VFD is equipped with a by-pass?
16. Can I use a single LINEATOR™ to supply multiple VFD’s?
17. Can I get a computer simulation to demonstrate compliance with IEEE Std 519 or simply to show the LINEATOR™’s effectiveness in a specific application?
18. What kind of performance guarantee does the LINEATOR™ have?
19. What information is required to properly apply the LINEATOR™ AUHF?