Below are a few questions our tech support team often answer, related to conducting arc flash analysis with EasyPower.
What’s the minimum level of data I need to perform my Arc Flash Hazard Analysis?
- All data fields marked as red text boxes or marked with a red exclamation point. Note: EasyPower will warn you of incomplete data when you close a dialog box.
- Protective device data
- Class, manufacturer, type, style as required (HV breakers lack style, for example) for breakers and trip units
- Phase trip data such as ST, LT and Inst pickup, delay, etc.
My incident energy levels seem to be rather high. What can I look for as a possible cause?
The most common issue resulting in higher-than-expected energy levels is the upstream protective device taking too long to trip. This happens because the trip device maybe be set incorrectly, sized improperly, does not have the required trip features, or sees only a reduced arcing current because the fault is on the other side of a transformer.
Reducing the arcing time, while maintaining protective device coordination, may require more advanced relay features or protective system design. Incident energy is also highly affected by working distance.
What is the most common reason for “no upstream trip device found” results when I run my analysis?
One of the most common reasons is the user forgetting to enter the trip data. We often see user systems that show the fuse or relay on the one-line, but there is no trip data in the dialog. This often occurs on the secondary of the main transformer where the user does not enter the utility trip device or data.
My HV breaker is not tripping! I know I have all the breaker data completed. What could it be?
High-voltage breakers do not contain trip units, and as such, require a relay to sense the fault and open the appropriate circuit. If you have applied a relay, be sure it has been correctly configured for the required function. Remember that in EasyPower arc flash hazard analysis is based on a three-phase fault; ground fault functions are not accounted for in the calculations.
