Resetting The Energies; Energy Pulsing; Harmonic Measurements; Measurement Technique - Satec System 295 Installation And Operation Manual

• net energy - the sum of imported and exported energy considering their sign.
Readings will represent difference between imported and exported energy
keeping the sign of the higher absolute value
• total energy - the sum of the absolute values of imported and exported
energy. Readings are always represented by a positive number indicating
integral power flow through load
For apparent energy, only total energy measurements are considered.
Energy readings can be in the range of 0 to ±999,999,999 kWh/kvarh/kVAh.
Beyond the maximum value, energy readings will wrap to zero.

4.4.2 Resetting the Energies

All the energy accumulating and keeping registers can be cleared simultaneously via
the front panel, communications, or by a programmable setpoint. By using
communications in broadcast mode, reset can be performed concurrently in all
instruments connected to a master computer.
The date and time of the last reset can be read via the instrument' s front panel.

4.4.3 Energy Pulsing

Each of four relays can be configured to provide the following pulses:
•
kWh imported
•
kWh exported (returned)
•
kWh total
The number of unit-hours per pulse can be configured from 1 to 9999.

4.5 Harmonic Measurements

4.5.1 Measurement Technique

Harmonic measurements are taken using on-board performed FFT analysis. The
FFT analysis is based on sophisticated sampling techniques using the sampling
frequency and the time window being exactly synchronized with the fundamental
frequency. The frequency filtration circuit provides very high accuracy of the
fundamental frequency measurements. High sampling rate of 128 samples per cycle
allows for on-board evaluation of harmonics up to 40th (with accompanying
software those can be extended up to 63rd).
64
•
kvarh imported (inductive)
•
kvarh exported (capacitive)
•
kvarh total
• kVAh total
Operation Techniques