CHINT Contactor NC1-2508/220V

Model Interpretation

Model Segment	Description
NC1	Product series code; CHINT Electric NC1 series AC contactor, suitable for remote on/off control of AC circuits and frequent control of AC motors
25	Rated operating current class; rated operating current is 25A under AC-3 utilization category (at 400V)
8	Auxiliary contact configuration, 0 normally open + 8 normally closed (actually a 4-pole contactor with 2NO+2NC main contacts; auxiliary contacts need to be configured separately)
220V	Rated control voltage of the coil; AC 220V, compatible with 50/60Hz frequency

Core Technical Parameters

Parameter Category	Specific Index
Rated Operating Voltage (Ue)	Three-phase AC 690V (50/60Hz); Rated Insulation Voltage Ui = 800V
Rated Operating Current (In)	25A at 400V under AC-3; 40A at 400V under AC-1; 16A at 690V under AC-3
Utilization Category	AC-1 (non-inductive or slightly inductive loads), AC-3 (starting/running/breaking of squirrel-cage induction motors), AC-4 (frequent starting/reversing/braking of squirrel-cage induction motors)
Main Contact Configuration	4-pole, 2NO+2NC (2 Normally Open + 2 Normally Closed)
Auxiliary Contacts	Need separate configuration (e.g., AX series auxiliary contact sets); can be expanded to combinations like 2NO+2NC
Coil Parameters	Rated voltage AC 220V, 50/60Hz; Pick-up power approx. 370VA; Holding power approx. 45VA
Mechanical Life	≥10 million cycles (no-load operation)
Electrical Life	≥100,000 cycles under AC-3 (breaking at rated current)
Protection Class	IP20 (prevents finger access)
Mounting Method	Standard 35mm DIN rail mounting or screw fixing
Compliance Standards	IEC/EN 60947-4-1, GB14048.4

III. Functional Features

Flexible Multi-Pole Configuration: 4-pole design (2NO+2NC main contacts) adapts to various circuit control requirements, especially suitable for scenarios requiring bidirectional control or switching of the main circuit.
Wide Voltage Compatibility: The coil supports universal 50/60Hz frequency, adapts to power grid frequencies in different regions, and ensures stable and reliable control voltage.
Long Mechanical and Electrical Life: Mechanical life up to 10 million cycles and electrical life of 100,000 cycles under AC-3, meeting the requirements of industrial scenarios with frequent start-stop operations.
Modular Expansion: Accessories such as auxiliary contact sets and mechanical interlock modules can be added to realize function expansion including signal feedback and reversible control.
Safe and Reliable Design: Adopts silver alloy contacts with strong anti-welding capability; the high-efficiency arc extinguishing system ensures short arcing distance during breaking, guaranteeing electrical safety.
High Versatility: Designed with reference to the Schneider LC1 series; can be matched with CHINT NR2 series thermal overload relays to form electromagnetic starters for overload protection.
Application Scope
Motor Control: Can control motors up to 11kW (400V three-phase induction motor) under AC-3 category, suitable for frequent start-stop of equipment such as fans, water pumps and conveyors.
Power Distribution System: Used for remote on/off control of circuits below AC 690V, such as control of non-inductive or slightly inductive loads (AC-1 category) like lighting systems and heating equipment.
Industrial Automation: Serves as the core component of control circuits such as star-delta starters and reversible contactors, adapting to various motor control schemes including DOL (Direct-On-Line) starting and star-delta starting.
Building Electrical Engineering: Control circuits of equipment such as fans, air conditioners and water pumps in shopping malls, office buildings, factory workshops and other places.
Not Suitable For: DC circuits, occasions with frequent reversing and large load inertia (AC-4 dedicated contactors are required), and heavy-duty circuits exceeding rated current.
Selection Suggestions
Load Matching:

Motor Load: Select according to motor power; 25A contactor is suitable for ≤11kW three-phase motors at 400V.

Power Distribution Load: Can carry 40A current under AC-1 category, suitable for lighting or heating loads with total power ≤17kW.

Control Voltage Confirmation: Ensure that the coil voltage (220V) matches the power supply of the control circuit to avoid coil burnout.
Auxiliary Contact Expansion:

For signal feedback: Install AX-02 auxiliary contact set (2NO).

For interlock control: Install mechanical interlock module (suitable for reversible control).

For alarm function: Install alarm contact module.

Protection Configuration: Use with NR2-25 series thermal overload relays with setting current 16-25A to achieve motor overload protection.
Brand Replacement Reference:

Brand	Replacement Model	Core Differences
Schneider	LC1D25008M7 220V	Higher price, same auxiliary contact configuration, slightly higher breaking capacity
Siemens	3RT6026-1AN20 220V	Modular design, compatible with Siemens automation systems, higher price
Delixi	CJX2-2508 220V	Domestic product of the same grade, consistent parameters, high cost performance

Troubleshooting

Common Faults	Possible Causes	Solutions
Coil not pulling in after power-on	1. Mismatched coil voltage or open circuit in control loop	1. Verify coil voltage and check control loop wiring
	2. Burned coil	2. Measure coil resistance (approx. several hundred ohms under normal condition); replace if burned
	3. Jammed mechanical mechanism	3. Clean the interior of the contactor and check for jamming of springs and armature
Loud noise after pull-in	1. Oil stain or rust on armature end face	1. Clean armature end face to remove oil stain and rust
	2. Broken shading ring	2. Replace shading ring or contactor body
	3. Low coil voltage	3. Check control power supply voltage to ensure it is within 卤10% of the rated value
Overheating or welding of contacts	1. Load current exceeding rated value	1. Replace with contactor of larger capacity or reduce load
	2. Poor contact of contacts	2. Clean contacts and polish oxide layer; replace contacts if severely damaged
	3. Failure of arc extinguishing system	3. Check for damage to arc extinguishing cover and replace in time
Abnormal signal of auxiliary contacts	1. Poor contact of auxiliary contacts	1. Clean auxiliary contacts and check wiring
	2. Loose installation of auxiliary contact set	2. Reinstall auxiliary contact set and tighten screws
	3. Severe wear of contacts	3. Replace auxiliary contact set
Frequent coil burnout	1. Excessive fluctuation of control voltage	1. Install voltage stabilizer or surge protector
	2. Long-term coil energization (exceeding design life)	2. Optimize control loop to avoid long-term coil energization
	3. High ambient temperature	3. Improve ventilation and heat dissipation conditions to reduce ambient temperature

VII. Installation and Maintenance Notes

Before installation, check that the contactor has no damage to appearance, no oxidation of coil and contacts, and the mechanical mechanism is flexible without jamming.
When installing on DIN rail, reserve ≥50mm heat dissipation space and avoid close installation with other heating elements.
During wiring, use wires suitable for 25A current for main circuit terminals (4mm² copper core cable is recommended) and tighten terminal screws (tightening torque 2.5N·m).
Use 1.5mm² copper core cable for control loop wiring to avoid excessive voltage drop due to insufficient wire diameter.
Conduct regular inspection every 3 months:

Check contact wear; replace when contact thickness is less than 1mm.

Monitor coil temperature; normal operating temperature should be ≤80℃.

Check flexibility of mechanical mechanism and remove dust and oil stains.

After a fault occurs, cut off power supply first, troubleshoot and repair before putting into use; operation with fault is strictly prohibited.

Parameter Comparison Table of CHINT NC1 Series Contactors (9A/12A/25A/40A/65A/95A)

Comparison Dimension	NC1-09	NC1-12	NC1-25	NC1-40	NC1-65	NC1-95
Rated Operating Current (AC-3, 400V)	9A	12A	25A	40A	65A	95A
Suitable Three-Phase Motor Power (400V)	4kW	5.5kW	11kW	18.5kW	30kW	45kW
Rated Operating Current (AC-1, 400V)	12A	18A	40A	63A	100A	150A
Rated Insulation Voltage (Ui)	800V	800V	800V	800V	800V	800V
Rated Operating Voltage (Ue)	AC 690V	AC 690V	AC 690V	AC 690V	AC 690V	AC 690V
Main Contact Configuration	3NO (3 Normally Open)	3NO	2NO+2NC (4-pole)	3NO	3NO	3NO
Coil Voltage Options	AC 24/36/110/220/380V	Same as left	Same as left	Same as left	Same as left	Same as left
Coil Voltage Options	DC 24/110V	Same as left	Same as left	Same as left	Same as left	Same as left
Coil Pick-up Power	Approx. 70VA	Approx. 85VA	Approx. 370VA	Approx. 500VA	Approx. 650VA	Approx. 800VA
Coil Holding Power	Approx. 8VA	Approx. 10VA	Approx. 45VA	Approx. 60VA	Approx. 80VA	Approx. 100VA
Mechanical Life	≥10 million cycles	≥10 million cycles	≥10 million cycles	≥10 million cycles	≥10 million cycles	≥8 million cycles
Electrical Life (AC-3)	≥100,000 cycles	≥100,000 cycles	≥100,000 cycles	≥100,000 cycles	≥100,000 cycles	≥80,000 cycles
Protection Class	IP20	IP20	IP20	IP20	IP20	IP20
Mounting Method	35mm DIN rail/screw fixing	Same as left	Same as left	Same as left	Same as left	Same as left
Matching Thermal Overload Relay	NR2-11.5	NR2-11.5	NR2-25	NR2-40	NR2-65	NR2-95
Typical Application Scenarios	Small fans, pumps, lighting control	Conveyors, small compressors	Central air conditioning fans, water pumps	Large fans, air compressors	Injection molding machines, crushers	Cooling towers, large motors

Supplementary Selection Tips

Load Matching Priority: For motor loads, select according to rated current under AC-3; for power distribution/lighting loads, select according to rated current under AC-1. The load current shall be ≤80% of the contactor’s rated current to avoid overload.
Coil Voltage Selection: Prioritize voltage consistent with the control loop (e.g., 220V). DC coils are suitable for industrial scenarios with strong electromagnetic interference to avoid false pull-in.
Auxiliary Contact Expansion: All specifications can be equipped with AX series auxiliary contact sets (2NO/2NC/1NO+1NC) to meet the needs of signal feedback and interlock control.
Reversible Control Configuration: Select 2 contactors of the same specification and install mechanical interlock module to prevent main circuit short circuit.