22
Power Quality Analyzer Model 3945
Factors affecting accuracy
(% of the output signal)
Conditions
Range
Error
Temperature
64 to 82°F (18 to 28°C)
Ζerο:
≤
2 A/°C
Scale:
≤
300ppm/°C or
0.3%/10°C
Relative humidity
10 to 90% RH
0.5% of Reading
Battery voltage
6.5 to 10V
≤
1 A/V
Position of a
20mm Ø 20 conductor
DC at 440Hz
DC at 1 Hz
DC at 2Hz
DC at 5Hz
<0.5% of Reading
<1% of Reading
<3% of Reading
<10% of Reading
Live adjacent conductor
50 and 60Hz
<10mA/A
AC
(1" from clamp)
External fi eld
400 A/m
<1.3A
Rejection in common mode (AC)
50 to 400Hz
>65dB
Remanence in DC
+1300A
DC
at -1300A
DC
<4mA/A
Frequency of the
measurement signal
65Hz to 440Hz
440Hz to 1kHz
1kHz to 10kHz
-2%
-5%
-4dB
3.10 Three Phase 5A Adapter
The three phase transducer has three 5A
AC
input current circuits L1, L2, L3 and
three output AC voltage circuits. All circuits are independent and isolated between
input and output. The output connectors are designed for use with the Model 3945
PowerPad™ with automatic sensor recognition and measurement adjustment.
The input connections accept either Ø4mm male plugs or rigid leads between 1 and
2.5mm
2
copper section inserted in the bottom hole after pressing on the connector.
Caution:
This adapter can be used on measurement Category III
for voltages not exceeding 300V in relation to the ground according
to IEC 61010.
3.10.1 Connecting to a secondary current transformer (CT)
1. Make a short circuit between the two leads of each secondary current mea-
surement transformer.
2. Never open a secondary circuit of a CT if its primary circuit is connected to a
supply voltage. In any case, disconnect the primary measurement transformer
circuit from the supply network.
3. Connect each CT secondary to the input of the 5A adapter paying attention to
the direction of the current fl ow (ground on P2) and the right phase order L1,
L2, L3.
