CQR2 Series Thermal overload relay
Product Features
■ Comprehensive Motor Protection: Designed for three-phase squirrel-cage asynchronous motors, providing reliable overload and phase-failure protection.
■ Wide Application Range: Suitable for AC systems up to 690V, with current ratings from 0.1A to 95A, supporting continuous or intermittent duty operations.
■ Functional Versatility: Features temperature compensation, trip indication, automatic/manual reset, and a stop function for enhanced control and safety.
■ Robust Design: Equipped with bimetallic strips (triple-phase), adjustable current settings, and auxiliary contacts (1NO + 1NC with electrical isolation).
■ Easy Integration: Plug-in installation compatible with CQC6 series contactors for streamlined assembly.
Operating & Environmental Conditions
■ Ambient Temperature: -5℃ to +40℃ (average temperature ≤ +35℃ Cover 24h).
■ Humidity: ≤50% at +40℃; ≤90% at lower temperatures (with condensation prevention).
■ Altitude: Up to 2000m.
■ Pollution Degree: Level 3.
■ Method: Plug-in installation combined with MHZC5 series contactors.
■ Enclosure Protection: IP20 (front-side).
Type designation
Selection Guide
Instructions for Use
CQR2 Series Thermal Overload Relay Panel Symbols and Functional Button Description
Trip Test (Performed BEFORE energizing the main circuit):
Open the cover. Press the test button with a screwdriver. The NC contacts will open and the NO contacts will close. The status change can be observed through the indicator window (yellow mark visible indicates tripped state; mark hidden indicates reset state – see illustration above).
Reset Mode Setting (Performed BEFORE energizing the main circuit):
The relay leaves the factory set to manual reset mode. To select automatic reset mode, press and hold the reset button while turning it clockwise 90°. It is not advisable to change the reset mode while the circuit is energized and running.
Setting Current Adjustment (Performed BEFORE energizing the main circuit):
The relay leaves the factory set to the minimum setting current. To select a different setting current value, open the cover and turn the current setting dial with a screwdriver. Align the arrow on the dial with the current value corresponding to the full-load rated current of the motor being protected.
Emergency Stop:
Press the Stop Button. Pressing the stop button only opens the NC contacts; it does not affect the NO contacts. Releasing the stop button resets the NC contacts.
Dimensions (mm)
CQR2-25
CQR2-38
CQR2-95
Technical Specifications
| Product Model | CQR2-25 | CQR2-38 | CQR2-95 | ||
| Current rating | 25 | 38 | 95 | ||
| Rated insulation voltage V | 690 | 690 | 690 | ||
| Rated impulse withstand voltage V | 6000 | 6000 | 6000 | ||
| Enclosure protection grade | IP20(Front side) | IP20(Front side) | IP20(Front side) | ||
| Phase loss protection | ● | ● | ● | ||
| Manual and automatic reset | ● | ● | ● | ||
| Temperature compensation | ● | ● | ● | ||
| Tripping indication | ● | ● | ● | ||
| Test button | ● | ● | ● | ||
| Stop button | ● | ● | ● | ||
| Installation method | Insertable | Insertable | Insertable | ||
| Auxiliary contact | 1NO+1NC | 1NO+1NC | 1NO+1NC | ||
| AC-15220V rated current A | 2.73 | 2.73 | 2.73 | ||
| AC-15380V rated current A | 1.58 | 1.58 | 1.58 | ||
| DC-13220V rated current A | 0.2 | 0.2 | 0.2 | ||
| Cross-sectional area of conductor(mm²) | Main circuit | Single-core or stranded wire | 1 ~ 4 | 6~10 | 6~35 |
| Wire connection screw | M4 | M4 | M10 | ||
| Auxiliary circuit | Single-core or stranded wire | 1 ~ 2.5 | 1~2.5 | 1-2.5 | |
| Wire connection screw | M3.5 | M3.5 | M3.5 | ||
Tripping Characteristics
| Item | No. | Setting Current Multiple | Operating Time | Purpose / Test Condition | |
| Overload Protection | 1 | 1.05 | No operation within 2 hours | Starting from Cold State | |
| 2 | 1.2 | Operation within 2 hours | Starting from Hot State (after Item 1) | ||
| 3 | 1.5 | Operation within 2 minutes | Starting after reaching thermal equilibrium at setting current | ||
| 4 | 7.2 | 2S<TP≤10S | Starting from Cold State | ||
| Phase Failure Protection | 5 | Any Two Phases | One Phase | No operation within 2 hours | Starting from Cold State |
| 1 | 0.9 | ||||
| 6 | 1.15 | 0 | Operation within 2 hours | Starting from Hot State (after Item 5) | |
Adjustable Trip Setting Range
| Product Model | Current adjustment range RC(A) | Plug-in contactors | Short-circuit protection fuse (A) | |
| aM | gG | |||
| CQR2-25 | 0.1~0.16 | CQC6(SM/KMNC1)-09 CQC6(SM/KMNC1)-12 CQC6(SM/KMNC1)-18 CQC6(SM/KMNC1)-25 |
0.25 | 2 |
| 0.16~0.25 | 0.5 | 2 | ||
| 0.25~0.40 | 1 | 2 | ||
| 0.40~0.63 | 1 | 2 | ||
| 0.63~1 | 2 | 4 | ||
| 1~1.6 | 2 | 4 | ||
| 1.6~2.5 | 4 | 6 | ||
| 2.5~4 | 6 | 10 | ||
| 4~6 | 8 | 16 | ||
| 5.5-8 | 12 | 20 | ||
| 7~10 | 12 | 20 | ||
| 9~13 | 16 | 25 | ||
| 12~18 | 20 | 35 | ||
| 17-25 | 25 | 50 | ||
| CQR2-38 | 23-32 | CQC6(SM/KMNC1)-32 | 40 | 63 |
| 30~38 | 40 | 80 | ||
| CQR2-95 | 17~25 | CQC6(SM/KMNC1)-40 CQC6(SM/KMNC1)-50 CQC6(SM/KMNC1)-65 CQC6(SM/KMNC1)-80 CQC6(SM/KMNC1)-95 |
25 | 50 |
| 23~32 | 40 | 63 | ||
| 30~40 | 40 | 100 | ||
| 37~50 | 63 | 100 | ||
| 48~65 | 63 | 100 | ||
| 55~70 | 80 | 125 | ||
| 63~85 | 80 | 125 | ||
| 80~95 | 100 | 160 | ||
Accessories Description
| Application | Model number | Application |
| MB-1 | Combined with M12 to form an independent mounting product | |
 |
MB-2 | Combined with M25 to form an independent mounting product |
 |
MB-3 | Combined with M38 to form an independent mounting product |
 |
MB-4 | Combined with M95 to form an independent mounting product |
Why Choose CHAC
With 30+ years of manufacturing experience, 1100+ employees, 100M+ poles
annual capacity and 90% automated production, CHAC provides stable production capacity and strict
quality control for global OEM/ODM customers. Our in-house manufacturing system supports long-term
cooperation for electrical brands, importers and distributors.
30+
YEARS EXPERIENCE
Specialized in low-voltage electrical manufacturing
1100+
EMPLOYEES
Professional team ensures stable quality and delivery
100M+
POLES ANNUAL CAPACITY
Large-scale production capacity to meet global demand
90%
AUTOMATED PRODUCTION
Advanced automation for high efficiency and consistency
Automated Assembly Line
Testing Laboratory
Injection & Stamping
Quality Inspection
Strict quality control system ensures every product meets global standards.
What Can We Customize?
CHAC supports customization of coil voltage, auxiliary contact configuration,
electrical parameters, product branding,packaging design and engineering development according to customers’ equipment and market requirements.
Coil Voltage
AC and DC coil voltage options tailored to application requirements.
Auxiliary Contacts
Flexible auxiliary contact combinations for different control functions.
Electrical Parameters
Current ratings, protection ranges and functional parameters can be customized.
Product Branding
Private label logos, nameplates and product identification support.
Packaging Design
Custom cartons, labels, manuals and packaging solutions.
Engineering Development
Support from drawing optimization to product development and application matching.
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CQR2 Series Thermal Overload Relay
Complete product overview for low-voltage electrical components and product selection reference.
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Frequently Asked Questions
Q1. Do you support product customization based on our design requirements?
A1:Absolutely. We specialize in OEM and ODM cooperation in the low-voltage electrical field and have provided customized services for many internationally renowned companies. We offer full-process support, including R&D design, parameter adjustments, and special material selection, ensuring the product fully meets your requirements.
Q2: What is your production capacity and Minimum Order Quantity (MOQ)?
A2: We operate a highly automated production base with an annual output of over 100 million poles for miniature circuit breakers. Our MOQ policy is flexible. We can provide competitive trial orders for small batches and dedicated production capacity guarantee plans.
Q3: What assurances are there for product quality and certifications?
A3: Our main products are certified with CCC, CE, CB, and more, and are sold in over 30 countries and regions worldwide. The company has established a dedicated Quality Operations Center that works with the business and production departments to implement full-process quality control, ensuring products meet international standards.
Q4: Do you have the capability for product R&D and turning concepts into reality?
A4: We have a complete R&D team and digital workshops, backed by extensive customization experience serving numerous international clients. From concept proposal and sample development to mass production, we provide end-to-end technical support to help bring your ideas to life.
