Is The Service Life Of The Neutral Block Short? These Extension Techniques Need To Be Understood
Terminal blocks are the core components of electrical connections, and their lifespan directly affects the stability of equipment operation. If there are frequent issues such as loosening, heating, or even burning, it is often related to improper installation techniques, environmental factors, or selection. Mastering the following extension techniques can significantly improve the service life of neutral blocks.
1、 Standardize installation processes to reduce mechanical damage
Precision control of torque
Use a torque wrench to tighten the screws according to the recommended torque value of the terminal manufacturer (such as 1.2-1.5N · m for copper terminals), to avoid increasing contact resistance due to looseness or damaging the insulation layer or causing thread slippage due to tightness. For example, a certain substation once caused local overheating due to excessive terminal torque, resulting in the crushing of the contact surface between copper bars and screws.
Standardization of wire pretreatment
When stripping, keep an appropriate length of insulation layer (about 5-8mm) to prevent bare wires from being exposed; Use a crimping tool to flatten the wire end and increase the contact area with the terminal piece; Multiple strands of wire need to be tinned to avoid burrs piercing the insulation layer or causing virtual connections.
2、 Optimize the usage environment and reduce the risk of corrosion
Moisture and dust prevention design
In humid environments such as coastal areas and basements, use neutral blocks with protection levels of IP65 or higher, or install dust covers; Regularly clean the dust on the surface of the terminal with dry compressed air to prevent the formation of conductive paths after dust accumulation and moisture absorption.
Selection of corrosion-resistant materials
In corrosive scenarios such as chemical and metallurgical industries, stainless steel (304/316L) or nickel plated copper terminals should be preferred over ordinary carbon steel materials; If rust has appeared, sandpaper should be used to polish it to a metallic luster, and conductive anti-corrosion paste (such as lubricating grease containing zinc particles) should be applied.
3、 Scientific selection and maintenance, matching load requirements
Rationalization of parameter matching
Select terminal specifications based on current and voltage levels (e.g. rated current should be ≥ 1.2 times the line load) to avoid long-term overload operation; Spring or locking terminals are selected for vibration scenarios such as motors and rail transit to enhance their anti loosening ability.
Regular inspection and replacement
Establish a terminal health record and check the contact resistance (measured with a micro ohmmeter, value should be ≤ 50 μ Ω), temperature (detected with an infrared thermometer, abnormal temperature rise ≥ 10 ℃ needs to be investigated), and insulation performance every six months; Replace terminals with severe aging (such as plastic shell cracking or metal discoloration) in a timely manner.
Case: A factory upgraded ordinary terminals to anti loose terminals with spring pressure plates and implemented a quarterly inspection system, reducing the terminal failure rate from 12 times per year to 2 times and reducing maintenance costs by 60%. Mastering these skills can prolong the life of neutral blocks and ensure the safe and efficient operation of electrical systems.
