Power Quality Issues
Performing a Power Quality Study 6
The following power conditioning suggestion chart is useful for choosing an adequate protection device for unrepetitive power line disturbances.
| Transient/ |
| Power Line |
| Swell |
| Filter |
| Protector |
|
|
Uninterruptible Power Supply
Transients
Swells
Sags
Outages
X*
X*
X
X
X
X
X
X
*Used only when transients and swells are moderate in quantity or else damage may occur to the power protection device.
When considering a protection device, make sure that it covers the entire operating range. It is a waste of money buying a protection device rated to remove transients of up to 1000 volts if you have recorded transients of more than this.
The difference between power line filters and protectors is that filters can catch fast transients of high magnitudes. Filters tend to be more expensive than protectors.
The information you receive from your recorder will enable you to make an informed decisions about protection devices.
Please note that this appendix is not a comprehensive study of power quality, nor does it attempt to provide all solutions to power quality problems.
Power quality is a complex issue. It may be necessary to make additional measurements such as: line current levels, harmonic content, and distortion using other power quality diagnostic equipment.
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