NLK1-0.66 0.66kV Indoor Current Transformer for Energy Metering and Relay Protection High Accuracy Sealed Anti Tamper Design ISO CE Certified Manufact
NLK1-0.66 Indoor Current Transformer is designed for low voltage power distribution systems up to 0.66kV, operating at 50/60Hz. It ensures accurate current measurement and reliable relay protection while providing electrical isolation from high voltage circuits. Featuring anti tamper sealed cover design, stable performance, ISO and CE certified quality, ideal for energy metering applications.
NLK1-0.66 SERIES TRANSFORMER
INDOOR CURRENT TRANSFORMER
SELECTION GUIDE
PRODUCT APPLICATION
NLK1-0.66 series transformers are indoor current transformers, which are suitable for rated frequency of 50(60)Hz.
Used for current and electric energy metering or relay protection in circuits with rated voltage of 0.66kV and below. And isolate measurement and protection from high voltage.
PRODUCT PARAMETER
| Brand | Newlink or OEM |
|---|---|
| Name | Current Transformer |
| Model | NLK1-0.66 |
| Rated Voltage | 0.66kW |
| Insulation Resistance | ≥20MΩ |
| Accuracy Level | 0.5 (Please contact us) |
| Rated Primary Current | 5A ~ 5000A |
| Rated Frequency | 50/60Hz |
| Power Factor | 0.8 (lag) |
| Rated Secondary Current | 5A |
| Rated Secondary Load | 2.5/5/10/15 VA |
| Power Frequency Withstand Voltage | 3kV (effective value) |
| Through the Bus Bar | Rated Current | Through Core Turns | Secondary Load 0.5 VA |
|---|---|---|---|
| NLK1-0.66/30 10x30 | 5 ~ 50 | 5 | 5 / 3.75 |
| 50 | 5 | 1 / 3.75 | |
| 75 | 5 | 2.5 | |
| 100 | 5 | 5 / 3.75 | |
| NLK1-0.66/30 10x30 | 150 | 5 | 5 / 3.75 |
| NLK1-0.66/40 10x40 | 200 ~ 500 | 5 | 5 / 3.75 |
| 750 ~ 1000 | 5 | 10 / 3.75 | |
| NLK1-0.66/50 10x50 | 300 ~ 600 | 5 | 5 / 3.75 |
| NLK1-0.66/60 6x60 | 750 ~ 800 | 5 | 10 / 3.75 |
| 1000 ~ 2000 | 5 | 15 | |
| NLK1-0.66/80 6x80 | 750 ~ 800 | 5 | 10 / 3.75 |
| 1000 ~ 2000 | 5 | 15 | |
| NLK1-0.66/100 10x100 | 750 ~ 800 | 5 | 10 / 3.75 |
| 1000 ~ 4000 | 5 | 15 | |
| NLK1-0.66/120 12.5x120 | 600 ~ 750 | 5 | 5 / 3.75 |
Shape and installation dimensions of multi-turn transformer
Shape and installation dimensions of single-turn transformer
| Model specification | Primary ampere turn | Overall dimension(mm) |
Installation dimension(mm) |
Corresponding window hole drawing(mm) | |||
|---|---|---|---|---|---|---|---|
| H | L | B | L1 | L2 | |||
| NLK1-0.66/30 | 75~100 | 116 | 90 | 50 | 40 | 59 | Figure A-30 type |
| NLK1-0.66/30 | 50 | 98 | 75 | 40 | 44 | 59 | Figure A-30 type |
| NLK1-0.66/30 | 75~100 | 98 | 75 | 40 | 44 | 59 | Figure A-30 type |
| NLK1-0.66/30 | 150~250 | 98 | 75 | 40 | 44 | 59 | Figure A-30 type |
| NLK1-0.66/30 | 150~500 | 80 | 60 | 36 | 32 | 59 | Figure A1-30 Type |
| NLK1-0.66/40 | 100~1000 | 98 | 75 | 40 | 44 | 59 | Figure B-40Type |
| NLK1-0.66/50 | 250~1600 | 98 | 82 | 40 | 50 | 59 | Figure C-50Type |
| NLK1-0.66/60 | 300~2000 | 126 | 102 | 40 | 50 | 59 | Figure D-60Type |
| NLK1-0.66/80 | 500~3000 | 118 | 125 | 40 | 50 | 59 | Figure E-80Type |
| NLK1-0.66/100 | 600~4000 | 136.5 | 170 | 40 | 80.3 | 59 | Figure F-100Type |
| NLK1-0.66/120 | 600~5000 | 153 | 190 | 46 | 100 | 59 | Figure G-120Type |
INSTALLATION DIAGRAM
Please install it according to the diagram or with the electrician.
The bus bar in the diagram needs to be prepared by yourself.
PAY ATTENTION TO
1. When installing the current transformer, one end of the secondary side should be reliably grounded.
2. The long-term working current of current transformer is not more than 1.1 times the rated current, and it is allowed to work at 1.2 times the rated current. Short run
3. The cross-sectional area of the connecting wire of the secondary circuit shall not be less than 1.5mm2, and the total impedance on the circuit shall not be greater than the current mutual. Secondary load of sensor
4. Use the current transformer in strict accordance with the current ratio on the nameplate, the number of turns passing through the center and the accuracy grade.
5. The same current transformer is not allowed to be used for both relay protection and electric energy metering.
1. Polarity: P1 is the inflow end of primary current; P2 is the outflow end of secondary current.
2. Identical terminals: P1 and S1, P2 and S2 are two pairs of identical terminals of the current transformer.
3. pass the primary wire through the window of the transformer and fix the transformer. Remove the protective cover at the top of the transformer and connect it properly.
Cover the protective cover on the back of the secondary circuit conductor.
4. different current ratios can be obtained by changing the number of turns of the primary conductor during installation. Number of turns (turns) of primary conductor threading = primary ampere turn ÷ actual current.
5. After confirming that the secondary circuit is connected, the transformer can be put into operation.
NORMAL WORKING AND
INSTALLATION CONDITIONS
● Ambient humidity: ≤80%
● Ambient temperature: -5°C ~+40°C
● Altitude: ≤1000m
● Installation place: indoors, without metal dust and violent vibration,
installation place There is no serious pollution in the atmosphere, and
there is no gas and conductive dust in the medium that can corrode
metals and destroy insulation.
● If the storage period is more than one year, the insulation resistance
should be measured once, and if it is less than 20MΩ, it should be
dried.
REAL SHOT DISPLAY
Product Details
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FAQs
Explore our FAQ section for clear guidance on orders, shipping, customization, and after-sales service.
Current Transformer（CT）
Can the primary conductor pass multiple turns through the window?
Yes. The actual primary ampere turns equal the number of conductor turns multiplied by the actual current. This allows flexible current ratio adjustment.
What is the rated voltage of NLK1-0.66 current transformer?
It is designed for low voltage systems up to 0.66kV and operates at 50/60Hz, suitable for indoor distribution applications.
Is secondary grounding required during installation?
Yes. One side of the secondary winding must be reliably grounded to ensure safety and prevent dangerous open circuit conditions.
Can this current transformer be used for both energy metering and relay protection?
No. One current transformer should be used either for energy metering or for relay protection, not both at the same time, to ensure measurement accuracy.
What is the recommended secondary wiring size?
The cross sectional area of the secondary connection wire should not be less than 1.5mm² to ensure stable and safe operation.
What certifications does this current transformer have?
The product is manufactured under strict quality control and complies with ISO and CE certification standards.
Does the product support anti tamper protection?
Yes. It is equipped with a protective cover and sealing hole. Lead sealing can prevent unauthorized opening and electricity theft.
What happens if the secondary circuit is open while the primary is energized?
The secondary must never be open circuited under load. It may generate high voltage and damage the transformer or create safety risks.
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