Multi-Tech Systems 7500, 7600 manual Flicker

ION 7500 / ION 7600 User’s Guide Flicker

Flicker

The flicker values Pst (short-term) and Plt (long-term) are generated according to

IEC 61000-4-15.

Observation period of one week with fixed Pst intervals of 10 minutes. A Pst value is considered valid only if the supply voltage is within ±15% of nominal and/or there is no voltage dip >= 15%.

N = number of Plt values collected during the observation period (based on 12 valid consecutive Pst values).

N1 = number of intervals in which Plt > 1.

Flicker complies with the standard if N1/N <= 5% during the observation period (1 week by default).

NOTE

Flicker is typically caused by rapid repeated application of large loads. This causes a series of small voltage dips which can affect the performance of nearby devices that are voltage sensitive. A voltage flicker problem can often be observed by the naked eye by noticing flickering lights.

EN 50160 data (current observation period): The meter generates the N and N1 counts for each phase as described above. These counters are reset at the beginning of the next observation period.

EN 50160 data (previous observation period): The meter stores the N and N1 counter values at the end of each observation period before these counters are reset. These 6 registers are also stored in a data recorder for each observation period.

Events: The meter creates a message in the Event log every time the N1 counter for each phase increases.

Parameter data: The meter can be enabled to record Pst and Plt values in a data recorder at the interval used to generate these values (10 minutes and 10 x 12 = 2 hours, respectively).

Power Quality: ION Meters and EN50160 Technical Note Page 307