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N° 97.13.36.000.0
IPN = 125 A
Features
●Closed loop (compensated)
current transducer using the Hall
effect
●Insulating plastic case recognized
according to UL 94-V0.
Advantages
●Excellent accuracy
●Very good linearity
● Low temperature drift
●Optimized response time
● Wide frequency bandwidth
●No insertion losses
●High immunity to external
interference
● Current overload capability.
Applications
●AC variable speed drives and
servo motor drives
●Static converters for DC motor
drives
●Battery supplied applications
● Uninterruptible Power Supplies
(UPS)
● Switched Mode Power Supplies
(SMPS)
● Power supplies for welding
applications.
Application domain
● Industrial.
Current Transducer LA 125-P
For the electronic measurement of currents: DC, AC, pulsed...,
with galvanic separation between the primary circuit and the secondary
circuit.
Electrical data
IPN Primary nominal current rms 125 A
IPM Primary current, measuring range 0 .. ± 200 A
RM Measuring resistance TA = 70 °C TA = 85 °C
RM min RM max RM min RM max
with ± 12 V @ ± 125 A max 5 52 14 50 Ω
@ ± 200 A max 5 20 14 18 Ω
with ± 15 V @ ± 125 A max 25 74 40 72 Ω
@ ± 200 A max 25 34 40
1) 40
1) Ω
ISN Secondary nominal current rms 125 mA
KN Conversion ratio 1 : 1000
UC Supply voltage (± 5 %) ± 12 .. 15 V
IC Current consumption 16 (@ ± 15 V) + IS mA
Accuracy - Dynamic performance data
X Accuracy @ IPN, TA = 25 °C @ ± 15 V (± 5 %) ± 0.60 %
@ ± 12 .. 15 V (± 5 %) ± 0.80 %
εL Linearity error < 0.15 %
Typ Max
IO Offset current @ IP = 0, TA = 25 °C ± 0.40 mA
IOM Magnetic offset current 2) @ IP = 0 and specied RM,
after an overload of 3 x IPN ± 0.50 mA
IOT Temperature variation of IO 0 °C .. + 70 °C ± 0.15 ± 0.50 mA
- 40 °C .. + 85 °C ± 0.30 ± 0.95 mA
tra Reaction time < 500 ns
tr Step response time 3) 4) to 90 % of IPN < 1 µs
di/dt di/dt accurately followed 4) > 200 A/µs
BW Frequency bandwidth 4) (- 1 dB) DC .. 100 kHz
General data
TA Ambient operating temperature - 40 .. + 85 °C
TS Ambient storage temperature - 40 .. + 90 °C
RS Secondary coil resistance @ TA = 70 °C 32 Ω
 @ TA = 85 °C 33.5 Ω
m Mass 40 g
Standard EN 50178: 1997
Notes: 1) Measuring range limited to ± 180 A max
2) Result of the coercive eld of the magnetic circuit
3) With a di/dt of 100 A/µs
4) The primary conductor is best lling the through-hole and/or the return of
the primary conductor is above the top of the transducer.
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23April2013/version 14 LEM reserves the right to carry out modications on its transducers, in order to improve them, without prior notice www.lem.com
Current Transducer LA 125-P
Isolation characteristics
Ud Rms voltage for AC insulation test, 50 Hz, 1 min 3 kV
ÛW Impulse withstand voltage 1.2/50 µs 7 kV
Min
dCp Creepage distance 6.7 mm
dCI Clearance 6.7 mm
CTI Comparative Tracking Index (group IIIa) 175
Applications examples
According to EN 50178 and IEC 61010-1 standards and following conditions:
●Over voltage category OV 3
●Pollution degree PD2
● Non-uniform eld
Safety
This transducer must be used in limited-energy secondary circuits according to
IEC 61010-1.
This transducer must be used in electric/electronic equipment with respect to
applicable standards and safety requirements in accordance with the manufacturer’s
operating instructions.
Caution, risk of electrical shock
When operating the transducer, certain parts of the module can carry hazardous
voltage (eg. primary busbar, power supply).
Ignoring this warning can lead to injury and/or cause serious damage.
This transducer is a build-in device, whose conducting parts must be inaccessible
after installation.
A protective housing or additional shield could be used.
Main supply must be able to be disconnected.
EN 50178 IEC 61010-1
d
Cp
, d
CI
, Û
W
Rated insulation voltage Nominal voltage
Basic insulation 600 V 600 V
Reinforced insulation 300 V 300 V
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Connection
Dimensions LA 125-P (in mm)
Mechanical characteristics
● General tolerance ± 0.2 mm
● Primary through-hole 17 × 4.5 mm
13 × 11 mm
●Fastening & connection of secondary 4 pins
0.63 x 0.56 mm
Recommended PCB hole 0.9 mm
●Supplementary fastening 2 holes Ø 1.75 mm
Recommended PCB hole 2.4 mm
Recommended screws PT KA 22 x 6
Recommended fastening torque 0.5 N·m
Remarks
●IS is positive when IP ows in the direction of the arrow.
●Temperature of the primary conductor should not exceed
100 °C.
●Dynamic performances (di/dt and response time) are
best with a single bar completely lling the primary hole.
● This is a standard model. For different versions (supply
voltages, turns ratios, unidirectional measurements...),
please contact us.
IS
IP