Multi-Tech Systems 7500 Power Frequency Default Measurements, Source Module Type Description

ION 7500 / ION 7600 User’s GuidePower Frequency

Power Frequency Default Measurements

Register Label	Source Module Type	Description
Freq N*		number of valid intervals (voltage on all phases within +/- 15% of nominal)
Freq N invld*	Signal Limit Evaluation	number of invalid intervals
Freq N1*		number of valid intervals in which the freq deviates from the nominal by more than +/-1%
Freq N2*		num of valid intervals in which the freq deviates from the nominal by more than +4% or -6%
PO Freq N		Freq N of the previous Observation Period
PO Freq N1	Store	Freq N1 of the previous Observation Period
PO Freq N2		Freq N2 of the previous Observation Period
Freq mean-ep	Sliding Window Demand	average Frequency over 10s (used for display purposes)
Freq mn-op	Minimum	minimum mean Frequency (Freq mean-ep) over 1week (used for display purposes)
Freq mx-op	Maximum	maximum mean Frequency (Freq mean-ep) over 1week (used for display purpose)
Freq N1/N		N1/N ratio
Freq N2/N	Arithmetic	N2/N ratio
PO Freq N1/N		N1/N ratio of the previous Observation Period
PO Freq N2/N		N2/N ratio of the previous Observation Period

* This data is recorded once a week by Data Recorder module 17.

Optionally, the data below can be recorded every 10 minutes by Data Recorder 32.

Register Label	Description
PQ Freq mean	average Frequency over 10minutes
PQ Freq low	minimum Frequency over 10 minutes (HS measurement)
PQ Freq high	maximum Frequency over 10 minutes (HS measurement)

Power Quality: ION Meters and EN50160 Technical Note Page 303