Specifications

Leakage Current Transducers [Insulated]
Leakage current transducers detect leakage current in AC cables using a Zero-current
transformer (ZCT) and output DC current or DC voltage proportional to the leaking current
value.
Applications
Preventive and predictive maintenance management of insulation degradation
in electrical equipment
Detection of leakage current in AC cables
T-51/T-101 Series
Transducers
143
T-51LG
0.4kg
(main unit only)
15mA
30mA
100mA
200mA
500mA
1A
5A
ZT15B
ZT30B
ZT40B
ZT60B
ZT80B
ZT100B
(Specify)

40Hz~2kHz1.0
1% P-P or less
1s or less
Accessory
(ZCT)
Delivery
period
classification
Weight
Auxiliary
power supply
ZCT Input (AC) Output (DC)
Current
Voltage or current and load Ripple/Response speed Frequency
1mA :
5mA :
4~20mA :
100mV :
1V :
5V :
10V :
1~5
V :
0~5kΩ
0~1kΩ
0~600Ω
5kΩ~
∞
5kΩ~
∞
5kΩ~
∞
10k
Ω
~∞
5kΩ~
∞
Outer shape
Box
Model name
Accuracy
(grade)
110VAC
%
50 and 60Hz
Consumption
VA: 3
+10
-15
Standard
product
Immediate delivery
 Quasi-standard
product
Within 20 days
Special
product
21 to 60 days
Symbol
Reference delivery period
Delivery period classification
When a harmonic component is contained in the measured circuit, the
T-51LG measures the effective value of the leakage current including
the harmonic component.
The ZCT is a dedicated accessory, and thus cannot be used in
combinations other than those specified for the transducer.
If the power supply frequency (fi) and output frequency (fo) are
connected close to each other in the inverter circuit, a beat may occur
in the leakage current and the output may fluctuate.
Influence of external magnetic field
An error of approximately 0.4% may occur if an external magnetic field
of 200A/m is applied to the main unit and ZCT.
Insulation between the input circuit and output circuit.
The input terminals and output terminals of the main unit are
not insulated.
The measurement circuit (input side) and output circuit can be insulated
using an accessory ZCT.
*2
*3
*4
*5
*6
Two-core shielded wire of
0.5~2.0mm
2
(CVVS, etc.)
25m or less one way
Shielded wire specifications Allowable lead length
Auxiliary
power
supply
Input
24V±10%
100, 105, 110, 115, 120V
%
200, 210, 220, 230, 240V
15mA~5A
0.1~20mA, 50mV~10V
DC
Output
AC
+10
-15
T-51LG
Lead wire specifications (between ZCT and transducer)
Make sure to use shielded wires.
Connect the shield (drain line) to the “±” input terminal.
*1
Manufacturable range
Connection diagrams
(Refer to p.156 for outer dimensions.)
(Refer to p.146 for outer dimensions of the ZCT.)
OUTPUT
INPUT
Output
Auxiliary power supply
Load
0.5~2.0mm
2
two-core
shielded wire
A ±
M
A MB
ZCT
Fig. 1 T-51LG
Usage example
ZCT
Leakage current
transducer T-51LG
Data logger,
indicator,
recorder
Input/Output relationships
0
0
2.5
5
V
0
0.5
1
mA
50 100mA
0 100 200mA
0
0
3
5
V
0
14
12
20
mA
7.5 15mA
0 15 30mA
DC output DC output
DC input DC input
T-51LG ZCT