From the experts
Evaluator Guide for Line Sensors
Line sensors for overhead and underground electric distribution circuits are a proven technology. Powerful sensing and long-range communications enable increased visibility of distribution system data for grid operators. But solutions vary, so when evaluating line sensing solutions be sure to consider the following criteria.
|Evaluation Criteria||Questions to Consider|
|1. Fault Detection Technology||Are current thresholds sufficient for fault detection, or are additional remotely
configurable algorithms such as di/dt or % change important?
|2. Accuracy||What accuracy is needed for both load data and fault magnitude? Fault
magnitude may be used for “Distance to Fault” calculations.
|3. Fault Magnitude Range||Sensors vary greatly on fault magnitude range. What is your upper limit required
for fault magnitude range?
|4. GPS Location and Timing||GPS is an important capability for verifying location and time stamping for
sequence of events. Are these requirements?
|5. Sampling Rate||Sampling rates for waveforms vary from 20/cycle to 256/cycle. What resolution
of waveform data is adequate for your fault analysis?
|6. Disturbance Capture||Can sensors can report disturbances in addition to faults with outages?
Disturbances can identify precursors to faults.
|7. Load Unbalance Analysis||Most sensor systems report load data. Can the system also identify and
quantify phase unbalance on 3-phase feeders?
|8. LED Visibility||The visibility of LEDs indicating faults can vary greatly.What LED visibility is
required for your distances and lighting conditions?
|9. Wireless Communications||Which wireless technologies are supported (cellular, mesh)? Are separate
gateways and RTUs needed in addition to sensors?
|10. Power Requirements||Is the system fully line-powered (at what amperage?), or does it require AC
power and use of batteries?
|11. Conductor and Equipment Types||Overhead: what is maximum conductor size and voltage? Underground: can you
install in livefront and deadfront cabinets?
|12. Environmental Ruggedness||Has the system been qualified to operate in harsh environments in terms of
temperature, humidity, salt spray, ingress etc.?
|13. Field Proven Solution||Has the solution been deployed successfully in the field? What size (number of
sensors) are the largest deployments?
|14. Product Roadmap||Does the solution provider have a long-term product development plan including updates and enhancements?|
To learn more about best practices and use cases for line sensing visit sentientstage.wpengine.com or email firstname.lastname@example.org.