Full technical review FNIRSI LCR-ST2 | Specs, Features & Feedback

Product Introduction

The FNIRSI LCR-ST2 Mini Smart Tweezer emerges as a crucial tool in the demanding field of electronics, where precision and efficiency are paramount. This innovative device directly addresses the challenge of accurately measuring and identifying passive components, particularly small surface-mount devices (SMD), which are increasingly prevalent in modern circuit designs. Its unique blend of a compact, tweezer-style form factor with advanced LCR and voltage testing capabilities sets it apart from bulkier, traditional benchtop meters. Designed for a diverse audience, from seasoned electronics engineers and field technicians to enthusiastic hobbyists and students, the LCR-ST2 is engineered to streamline circuit testing, component verification, and troubleshooting processes, making it an indispensable asset for any electronic project requiring high-accuracy measurements on the go or at the workbench. Check out our other technical reviews for more hardware testing.

Hardware specifications

Core Specifications: FNIRSI LCR-ST2

Model: LCR-ST2
Dimensions: 31×170.7×20.3mm
Weight: Approximately 60.8g
Screen Display: 1.47-inch HD color screen
Battery: 300mAh lithium battery
Power Type: Rechargeable
Charging Port: Type-C
Standby Time: Approximately 3 hours
Auto Power-off: Configurable (Never/ 5/15/30min)
Language: English / Chinese
Operating Temperature: 0°C ~ 50°C (Humidity <75%)
Storage Temperature: -20°C ~ 60°C (Humidity <75%)
Capacitance Range: 1pF — 22mF
Inductance Range: 1uH — 10H
Resistance Range: 10mΩ — 10MΩ
Diode Forward Voltage Detection: ≤0.7V
Voltage Range: ±30V
Frequency Sweep: 100Hz — 100kHz
Certification: CE
Origin: Mainland China
High-concerned chemical: None
Laser hazard level: Class 1（<1mW）

Available Versions

Available Versions & Selection Guide

The FNIRSI LCR-ST2 is available in two distinct configurations to cater to varying user needs:
1 LCR-ST2 Set 1**: Includes the LCR-ST2 Host with a Tweezer-Style Clip, a Storage Bag, a Curved Tip, a Shorting Plate, and a Data Cable.
2 LCR-ST2 Set 2**: Expands upon Set 1 by adding a Kelvin Test Clip, alongside the LCR-ST2 Host with Tweezer-Style Clip, Storage Bag, Curved Tip, Shorting Plate, and Data Cable..

Package Contents

What’s in the Box?

LCR-ST2 Set 1:
* LCR-ST2 Host + Tweezer-Style Clip
* Storage Bag
* Curved tip
* Shorting Plate
* Data Cable
LCR-ST2 Set 2:
* LCR-ST2 Host + Tweezer-Style Clip
* Storage Bag
* Curved tip
* Shorting Plate
* Kelvin Test Clip
* Data Cable

Features and benefits

Why I love FNIRSI LCR-ST2

The FNIRSI LCR-ST2 Mini Smart Tweezer offers a comprehensive suite of features designed to enhance electronic testing efficiency and accuracy. Its High-Accuracy Dual-Mode Measurement capability is a cornerstone, allowing users to precisely measure capacitance from 1pF to 22mF, inductance from 1uH to 10H, and resistance from 10mΩ to 10MΩ. The device automatically adjusts to provide optimal results across these ranges, with accuracy varying by frequency: for capacitance, it can be as precise as 0.5% ±3 digits for 1nF-1µF at 1KHz/10KHz; for inductance, 0.5% ±3 digits for 10µH-1mH at 1KHz/10KHz; and for resistance, 0.5% ±3 digits for 1kΩ-1MΩ at 1KHz. This ensures reliable data for a vast array of passive components.
The 100kHz Frequency Support is a significant advantage, enabling the testing of high-frequency components crucial for advanced electronics work. This broad frequency sweep, ranging from 100Hz to 100kHz, allows for a more thorough characterization of components, revealing their behavior under various operating conditions. For instance, capacitance measurements for 1nF-1µF maintain a 5% ±3 accuracy even at 100KHz, and inductance for 10µH-1mH also achieves 5% ±3 at 100KHz, providing valuable insights into component performance in high-frequency circuits.
Beyond LCR measurements, the device boasts 30V Voltage Testing capabilities, allowing for accurate measurement of components up to ±30 volts. This broad voltage range makes the LCR-ST2 versatile enough to handle a wide variety of circuits, from low-voltage logic to more robust power systems. Additionally, it includes Diode Forward Voltage Detection for values up to ≤0.7V, further expanding its utility for basic semiconductor testing.
The Mini Smart Tweezer design emphasizes portability and ease of use. With compact dimensions of 31×170.7×20.3mm and a lightweight build of approximately 60.8g, it fits comfortably in hand, making it ideal for both benchtop work and on-site field measurements. The 1.47-inch HD color screen provides clear, high-resolution display of all measurement data, enhancing user experience. The inclusion of a Type-C charging port and a 300mAh lithium battery with approximately 3 hours of standby time ensures convenient power management and extended operational periods.
Furthermore, the FNIRSI LCR-ST2 integrates Smart Technology for Enhanced Performance, featuring an intuitive interface that simplifies navigation through different settings and modes. Users can configure auto power-off settings (Never/ 5/15/30min) to conserve battery life. The device also supports both English and Chinese languages, catering to a global user base. Its durable construction, coupled with overvoltage and overcurrent protection, ensures long-lasting performance and safeguards both the device and the components under test, making it a reliable tool for beginners and professionals alike. The option to purchase Set 2 with a Kelvin Test Clip further enhances its precision for measuring components not on a PCB, minimizing contact resistance errors.

Pros and Cons

Strengths & Weaknesses:

What I Like

High-accuracy LCR measurements across a wide range of frequencies (100Hz-100kHz)
Compact, lightweight, and ergonomic tweezer-style design for easy handling of SMD components
Dual-mode measurement for LCR and voltage/diode testing
Wide voltage testing range of ±30V
1.47-inch HD color screen for clear data display
Convenient Type-C charging and a 300mAh rechargeable battery
Option for Kelvin Test Clip (Set 2) for enhanced precision
Fast measurement speed and intuitive user interface
Durable construction with overvoltage and overcurrent protection
Supports multiple languages (English/Chinese)

Points to Consider

Limited diode forward voltage detection (≤0.7V) may not cover all diode types
Not designed for in-circuit measurements, which can lead to inaccurate readings
Battery capacity of 300mAh might be considered small for extended heavy use
Some user reports indicate potential quality control issues (e.g., loose contacts, joystick malfunction)
Accuracy may vary or be less precise at the extreme ends of measurement ranges or specific frequencies (e.g., 1MΩ-10MΩ resistance at 10KHz/100KHz is not specified)

Price and Availability

Where to Buy & Customer Reviews

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Store info

STORE

⭐ 98.6% Positive Feedback | 123.0K Followers

Name:	FNIRSI Official Store
Store no.:	2939001
Location:	China
Open since:	Feb 26, 2017

Detailed seller ratings

Item as Described	4.9 Above Average
Communication	4.9 Above Average
Shipping Speed	4.9 Above Average

OTHER GOODS

User reviews

User Reviews & Feedback Analysis ⭐ 4.8 (53) | Sold (239)

Reviews FNIRSI LCR-ST2

Authentic Feedback Analysis:
⭐ 5.0/5 | M***i: A good set for measuring RLC components, it is quite accurate to thousandths of values, will be tested further but is comfortable to use.
⭐ 5.0/5 | К***ч: I have the previous version of these measuring tweezers. The differences are like night and day. The new version has an ideal design and functionality. It seems that when switching probes, a short-circuit calibration is needed — but even then, the accuracy of resistance measurement fluctuates in milliOhms. When first turned on, a contact in the tweezers was loose — I disassembled and reassembled it — now everything works. The coating of the tweezer tips and Kelvin probes is pure gold. As a multi-functional probe, it is almost perfect. Highly recommended!!!
⭐ 5.0/5 | Ю***т: The tweezers are convenient, good, you don’t get tangled in wires, you don’t think where to put a desktop multimeter. It shows readings instantly. I advise buying with Kelvin probes, good for measuring components not on a board.
⭐ 5.0/5 | AliExpress Shopper: Nice, high-quality tester, fast delivery, sturdy packaging. FNIRSI is always at the height of quality and service. My sincere recommendations to the company.
⭐ 5.0/5 | А***в: The device arrived well-packaged at a Yandex pickup point. Flashed the latest firmware, convenient, good accuracy.
⭐ 5.0/5 | Ж***ч: Very well packaged. The product is protected from damage. I bought it specifically for checking small capacitance SMD elements. Readings are good. I recommend the seller.
⭐ 5.0/5 | Л***ч: For its money — a good tool. No in-circuit measurement, for measuring diodes — weak voltage (up to 0.6 volts). Excellent speed. Small battery capacity.
⭐ 5.0/5 | Л***ч: A good device for everyday use. Very convenient and fast to work with. Recommended.
⭐ 5.0/5 | С***ч: Excellent device. Pleasant to interact with and hold 🙂 Convenient. I liked it.
⭐ 5.0/5 | К***а: Received. Excellent quality. Checked against an R standard, all good.
⭐ 5.0/5 | H***a: Thanks for fast delivery 💓🚚 Testing very accurately 💓🫶💯
⭐ 5.0/5 | В***к: The product is very well packed. Arrived quickly. Works great!!!
⭐ 5.0/5 | Ш***ч: Useful device, excellent quality.
⭐ 5.0/5 | Ж***й: Excellent device!
⭐ 5.0/5 | E***r: very good product thanks
⭐ 5.0/5 | Б***ч: Received the mini-tweezers. Everything works. Haven’t found any negative points yet.
⭐ 5.0/5 | Ж***ч: Everything corresponds to the description! Pleased!
⭐ 5.0/5 | AliExpress Shopper: corresponds to the description, seems of good quality, good finish, to see when using it if it works well
⭐ 5.0/5 | В***в: Working device, looks nice.
⭐ 5.0/5 | AliExpress Shopper: Thanks
⭐ 3.0/5 | П***ч: For measuring anything on a board, it’s useless, shows the weather, not readings. A regular multimeter measures everything accurately.
⭐ 4.0/5 | Т***в: Does not work correctly in the entire range.
⭐ 1.0/5 | М***ч: The order was placed on 01.02.20926. At the seller’s website, the product was sold at that time only without Kelvin probes. I asked the seller to add Kelvin probes to the order, but he offered me oscilloscope probes instead.
⭐ 1.0/5 | Е***ч: Defect. Trash! The tweezers don’t work. Turns on, turns off, charging works and nothing else! The joystick-carousel doesn’t work! And without it, nowhere. Be careful here!
⭐ 5.0/5 | Ж***й:
⭐ 5.0/5 | Ш***ч:
⭐ 5.0/5 | AliExpress Shopper:
⭐ 5.0/5 | Н***ч:
⭐ 5.0/5 | К***н:
⭐ 5.0/5 | O***n:
⭐ 5.0/5 | Т***ч:
⭐ 5.0/5 | Б***а:
⭐ 5.0/5 | AliExpress Shopper:
⭐ 5.0/5 | М***А:
⭐ 4.0/5 | AliExpress Shopper:

Pinout and Interface Map

PRODUCT PARAMETER FNIRSI LCR-ST2

FNIRSI LCR-ST2

Comparison table

Technical Specifications & Comparison FNIRSI LCR-ST2

Parameter	Range	100Hz/120Hz Accuracy	1KHz Accuracy	10KHz Accuracy	100KHz Accuracy
Capacitance	1mF-22mF	5% ±3	5% ±3	/	/
	1µF-1mF	2% ±3	2% ±3	2% ±3	5% ±3
	1nF—1µF	2% ±3	0.5% ±3	0.5% ±3	5% ±3
	1pF-1nF	/	2% ±3	2% ±3	5% ±3
Inductance	1H-10H	5% ±3	5% ±3	/	/
	1mH-1H	2% ±3	2% ±3	2% ±3	5% ±3
	10µH-1mH	2% ±3	0.5% ±3	0.5% ±3	5% ±3
	1µH-10µH	/	2% ±3	2% ±3	5% ±3
Resistance	1MΩ-10MΩ	5% ±3	5% ±3	/	/
	1kΩ-1MΩ	1% ±3	0.5% ±3	1% ±3	/
	1Ω-1kΩ	1% ±3	0.5% ±3	1% ±3	5% ±3
	10mΩ-1Ω	2% ±3	2% ±3	2% ±3	5% ±3
Diode & Voltage	On-state voltage ≤0.7V	/
Diode & Voltage	Voltage range ±30V	/

Final summary

Final Verdict: FNIRSI LCR-ST2

The FNIRSI LCR-ST2 Mini Smart Tweezer stands out as an exceptionally valuable tool for anyone involved in electronics, from professional engineers to hobbyists. Its combination of high-accuracy LCR measurements across a broad frequency range (up to 100kHz) and a wide voltage testing capability (±30V) in such a compact, portable form factor makes it a compelling choice. While it has minor limitations, such as the lack of in-circuit measurement and a relatively small battery, these are largely overshadowed by its precision, versatility, and user-friendly design, especially for working with SMD components. The option to include Kelvin test clips further enhances its appeal for those requiring utmost accuracy. For its price point, the LCR-ST2 offers significant value, making it an ideal investment for troubleshooting, component verification, and educational purposes, with its portability and ease of use being the primary advantages that truly set it apart. For more in-depth analyses, visit andibond.com.

FULL TECHNICAL REVIEW FNIRSI LCR-ST2 Mini Smart Tweezer