February 2011
2
INTRODUCTION
PEM‟s Rogowski Current Waveform Transducers combine high bandwidth, safety, and the minimum
disruption to the circuit under test. These instructions should be followed whenever the unit is used.
They are intended to help you obtain the best and safest performance from the transducer.
SPECIFICATION
ACCURACY (5 to 100% full scale)
Within the limits of bandwidth and low frequency noise that are specified on the relevant CWT
specification sheet.
Calibration:
Normally ±0.2% (traceable to UKAS) with the
conductor central in the CWT loop. See the calibration
certificate for more details.
Positional accuracy:
±1% typ. variation of accuracy with conductor position
in the loop (see „Obtaining The Best Measurement‟)
Linearity:
±0.05% typ.
POWER SUPPLY
The CWT can be powered by both battery
and
an external DC voltage. With the external DC supply
present the batteries are inoperative.
Battery type:
4 (four) 1.5V AA alkali
Battery life:
70 hrs typ.
DC socket type:
2.1 or 2.5mm jack socket
– polarity indicated on front of
CWT
DC voltage:
12V(-10%) to 24V(+10%)
DC quiescent supply current:
30mA (@12V DC) , 30mA (@ 24V DC)
When specified with
rechargeable batteries
the CWT operates directly from the batteries when there
is no DC supply present and is powered directly from the DC supply when present. With the DC
supply present the rechargeable batteries are permanently trickle charged.
Battery type:
4 (four) 1.2V NiMH rechargeable batteries
Battery life:
30 hrs typ. (based on a 1400mAH cell)
Recharge time:
40 hrs typ.
DC socket type:
2.1 or 2.5mm jack socket
– polarity indicated on front of
CWT
DC voltage:
12V(-10%) to 24V(+10%)
DC quiescent supply current:
70mA (@12V DC) , 70mA (@ 24V DC)
OUTPUT
Maximum output voltage:
±6V (corresponding to ±Peak Current Rating of CWT)
Output cable:
0.5m BNC to BNC 50Ω cable
Minimum output loading:
100kΩ
OPERATING TEMPERATURE RANGES
Rogowski coil and cable
-20
o
C to 100
o
C
Integrator electronics
0 to 40
o
C
