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N° 97.37.19.000.0
Current Transducer LTS 25-NP
For the electronic measurement of currents: DC, AC, pulsed..., with
galvanic separation between the primary circuit and the secondary
circuit.
Electrical data
IP N Primary nominal RMS current 25 At
IP M Primary current, measuring range 0 … ±80 At
Vout Output voltage (analog) @ IP 2.5 ±(0.625 × IP/ IP N) V
@ IP = 0 2.5 1) V
G Sensitivity 25 mV/A
NS Number of secondary turns (±0.1 %) 2000
RL Load resistance ≥ 2 kΩ
RI M Internal measuring resistance (±0.5 %) 50 Ω
TCRI M Temperature coecient of RI M < 50 ppm/K
UC Supply voltage (±5 %) 5 V
IC Current consumption @ UC = 5 V Typical 28 + IS
2) (Vout/RL) mA
Accuracy - Dynamic performance data
X Accuracy @ IP N, TA = 25 °C ±0.2 %
Accuracy with RI M,@ IP N, TA = 25 °C ±0.7 %
εL Linearity error < 0.1 %
Typ Max
TCVout Temperature coecient of Vout @ IP = 0 −10 ... +85 °C 50 100 ppm/K
−40 ... −10 °C 150 ppm/K
TCG Temperature coecient of G −40 ... +85 °C 50 3) ppm/K
VO M Magnetic oset voltage @ IP = 0,
after an overload of 3 × IP N ±0.5 mV
after an overload of 5 × IP N ±2.0 mV
after an overload of 10 × IP N ±2.0 mV
tra Reaction time @ 10 % of IP N < 100 ns
tr Step response time to 90 % of IP N 4) < 400 ns
BW Frequency bandwidth (0 ... −0.5 dB) DC … 100 kHz
(−0.5 ... 1 dB) DC … 200 kHz
General data
TA Ambient operating temperature −40 … +85 °C
TS Ambient storage temperature −40 … +100 °C
m Mass 10 g
Standards EN 50178: 1997
IEC 60950-1: 2001
Notes: 1) Absolute value @ TA = 25 °C, 2.475 < Vout < 2.525
2) IS = IP/ NS
3) Only due to TCRI M
4) For a di/dt = 60 A/μs.
IP N = 25 At
Features
● Closed loop (compensated)
current transducer using the Hall
eect
● Unipolar supply voltage
● Insulating plastic case recognized
according to UL 94-V0
● Compact design for PCB
mounting
● Incorporated measuring
resistance
● Extended measuring resistance.
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.
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UL 508: Ratings and assumptions of certication
File # E189713 Volume: 2 Section: 1
Standards
● CSA C22.2 NO. 14-10 INDUSTRIAL CONTROL EQUIPMENT - Edition 11
● UL 508 STANDARD FOR INDUSTRIAL CONTROL EQUIPMENT - Edition 17
Ratings
Parameter Symbol Unit Value
Primary involved potential V AC/DC 600
Max surrounding air temperature TA°C 85
Primary current IPAAccording to series primary
currents
Output voltage Vout V0 to 5
Conditions of acceptability
When installed in the end-use equipment, consideration shall be given to the following:
1 - These devices must be mounted in a suitable end-use enclosure.
2 - The terminals have not been evaluated for eld wiring.
3 - The LTS, LTSR, LTSP Series are intended to be mounted on the printed wiring board of the end-use equipment (with a
minimum CTI of 100).
4 - The LTS, LTSR, LTSP Series shall be used in a pollution degree 2 environment.
5 - Low voltage circuits are intended to be powered by a circuit derived from an isolating source (such as a transformer, optical
isolator, limiting impedance or electro-mechanical relay) and having no direct connection back to the primary circuit (other than
through the grounding means).
6 - The LTS, LTSR, LTSP Series: based on results of temperature tests, in the end-use application, a maximum of 100°C cannot
be exceeded at soldering point between primary coil pin and soldering point or on primary bus bar (corrected to the appropriate
evaluated max, surrounding air).
7 - For LTS, LTSR, LTSP Series, the secondary sensing circuit was evaluated as the circuit intended to be supplied from a Limited
Voltage/Current circuit dened in UL 508 standard.
Marking
Only those products bearing the UL or UR Mark should be considered to be Listed or Recognized and covered under UL’s Follow-
Up Service. Always look for the Mark on the product.
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Current Transducer LTS 25-NP
Insulation coordination
Ud RMS voltage for AC insulation test, 50 Hz, 1 min 3 kV
ÛW Impulse withstand voltage 1.2/50 μs > 8 kV
Ue Partial discharge extinction RMS voltage @ 10 pC 3 kV
Min
dCp Creepage distance 1) 15.5 mm
dCI Clearance 2) 6.35 mm
CTI Comparative tracking index (group IIIa) 175
Notes: 1) On housing
2) On PCB with soldering pattern UTEC93-703.
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
EN 50178 IEC 61010-1
dCp, dCI, ÛWRated insulation voltage Nominal voltage
Basic insulation 600 V 600 V
Reinforced insulation 300 V 300 V
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 (e.g. 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.
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Dimensions LTS 25-NP (in mm)
Mechanical characteristics
● General tolerance ±0.2 mm
● Transducer fastening of primary 6 pins 0.8 × 0.8 mm
Recommended PCB hole 1.3 mm
● Transducer fastening of secondary 3 pins 0.5 × 0.35 mm
Recommended PCB hole 0.8 mm
● Primary through-hole ⌀ 3.2 mm
Remarks
●Vout swings above 2.5 V when IP ows from terminals 1,
2, 3 to terminals 6, 5, 4 (with the arrow).
● Temperature of the primary conductor should not exceed
100 °C.
● Installation of the transducer must be done unless
otherwise specied on the datasheet, according to LEM
Transducer Generic Mounting Rules. Please refer to
LEM document N°ANE120504 available on our Web site:
Products/Product Documentation.
Connection
● This is a standard model. For dierent versions (supply
voltages, turns ratios, unidirectional measurements...),
please contact us.
Output voltage - Primary current
Number
of primary
turns
Primary
nominal
RMS
current
Nominal
output
voltage
Vout
Primary
resistance
RP [mΩ]
Primary
insertion
inductance
LP [µH]
Recommended
connections
1±25 2.5 ±0.625 0.18 0.013
6 5 4 OUT
IN 1 2 3
2±12 2.5 ±0.600 0.81 0.05
6 5 4 OUT
IN 1 2 3
3±8 2.5 ±0.600 1.62 0.12
6 5 4 OUT
IN 1 2 3
-IP M -IP N
IP N
0
V
out [ V ]
[ At ]
I
P
4.5
5
2.5
3.125
0.5
1.875
IP M
