Power Quality Analyzer Model 3945
13
C
HAPTER
3
S
PECIFICATIONS
3.1 Reference
Conditions
Parameter
Reference Conditions
Ambient temperature
73°F ± 5°F (23°C ± 3°C)
Humidity
45% to 75% RH
Atmospheric pressure
25.4" Hg to 31.3" Hg (860 to 1060 hPa)
Phase voltage
230Vrms and 110Vrms ±2% without DC
Clamp current circuit input voltage
0.01V to 1Vrms without DC (< 0.5%)
AmpFlex™ current circuit input voltage
3.9mV to 118mVrms without DC (< 0.5%)
Current input voltage detection threshold
0.001 In
Frequency of electricity network
50 and 60Hz ± 0.1Hz
V/I phase shift
0° active power / 90° reactive power
Harmonics
< 0.1%
The uncertainties given for power and energy measurements are maximum for Cos
ϕ
= 1 or Sin
ϕ
= 1
and are typical for the other phase shifts.
NOTE:
The symbol “U” will be used throughout this manual and in the instrument
to refer to phase-to-phase voltage measurement.
The symbol “V” will be used for phase-to-neutral voltage measurement.
3.2 Electrical
Specifi cations
Sampling Frequency (256 samples per cycle):
12.8kHz samples/sec per channel @ 50Hz
15.36kHz samples/sec per channel @ 60Hz
3.2.1 Voltage
Inputs
Operating Range:
Phase-Phase - 830Vrms AC/DC
Phase-Neutral - 480Vrms AC/DC
Input Impedance:
338k
Ω
between phase and neutral
Overload:
1.2Vn permanently; 2Vn for 1 sec (Vn = nominal voltage)
3.2.2 Current
Inputs
Operating Range:
0 to 1V
Input Impedance:
1M
Ω
for current probe circuit and 12.4k
Ω
for AmpFlex™ circuit
Overload:
1.7V
