Multi-Tech Systems 7600 ユーザーズマニュアル
Harmonic Voltage
ION 7500 / ION 7600 User’s Guide
Page 316
Power Quality: ION Meters and EN50160 Technical Note
Harmonic Voltage
All harmonic measurements are performed as defined by IEC 61000-4-7.
Observation period of one week with fixed steps of 10 minutes.
N = number of 10-minute intervals in which the supply voltage is within ±15% of
nominal.
nominal.
N
1
= number of intervals in which one or more of the individual harmonic levels
defined in the table below are exceeded and the supply voltage is within ±15% of
nominal. Levels for individual harmonics (for each phase) up to the 25th are
defined in the table below.
nominal. Levels for individual harmonics (for each phase) up to the 25th are
defined in the table below.
N
2
= number of intervals in which the THD value for one or more of the voltage
phases exceeds 8% and the supply voltage is within ±15% of nominal. The THD
calculation will include all harmonics up to the 40thd).
calculation will include all harmonics up to the 40thd).
Harmonic voltage complies with the standard if N
1
/N <= 5% and N
2
/N <= 5%
during the observation period (1 week by default).
EN 50160 data (current observation period): The meter generates the N, N
1
and
N
2
counts described above for each phase. These counters are reset at the
beginning of the next observation period.
EN 50160 data (previous observation period): The meter stores the N, N
1
and N
2
counter values at the end of each observation period before these counters are
reset. These 9 registers are also stored in a data recorder for each observation
period.
reset. These 9 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 N
1
and N
2
counters increase.
Parameter data: The meter can be enabled to record the 10-minute mean,
minimum and maximum values of THD, TO(odd)HD and TE(even)HD
minimum and maximum values of THD, TO(odd)HD and TE(even)HD
for each
voltage phase into a data recorder every 10 minutes.
Odd Harmonics
Even Harmonics
Not Multiples of 3
Multiples of 3
Order
Threshold
Order
Threshold
Order
Threshold
Order
Threshold
2
2%
5
6%
17
2%
3
5%
4
1%
7
5%
19
1.5%
9
1.5%
6…24
0.5%
11
3.5%
23
1.5%
15
0.5%
13
3%
25
1.5%
21
0.5%