Copper wire rod is a very ductile and malleable metal. It is high electrical conductivity and high thermal conductivity. Thus, copper parts have a significant advantage for the production of electronic and electrical components
Item Name
12.5mm and 8mm small diameter copper rod
Material
Copper, Brass,
Diameter
8-12.5 mm or as required
Length
as required
Hardness
O, 1/4 Hard, 1/2 Hard, 3/4 Hard, H, EH
Payment
Ex-work, FOB, CIF, etc
Package
Film / kraft paper/ bubble bag package.
Wooden pallet.
Woven bag with bundle in points
Delivery Time
Within 10 days after receipt of advance payment
Copper Rod,Stock Cooper Rod Brass Rod,Small Diameter Copper Rod,Copper Wire Rod HENAN HUAYANG ELECTRICAL TECHNOLOGY GROUP CO.,LTD , https://www.huaonwire.com
About Copper Rod
Relay, also known as an electric cymbal, is an electronic control device that consists of a control system (input circuit) and a controlled system (output circuit). It is commonly used in automatic control circuits and acts as an "automatic switch" by using a small current to control a larger one. This allows the relay to perform functions such as automatic adjustment, safety protection, and circuit switching. In circuit diagrams, the relay coil is represented by a long square symbol. If there are two coils, two long squares are drawn. The letter "J" is usually marked next to or inside the long square to indicate the relay.
The contacts of a relay can be represented in two ways: either directly drawn beside the long square for clarity, or shown in a more schematic manner. There are various types of relays, each with different working principles and structural features. Today, we will explore some common ones, including thermal relays, intermediate relays, and time relays.
A **thermal relay** works by generating heat when current flows through a heating element. It is primarily used for thermal protection, especially for motors against overload. The internal components include a heating wire, bimetallic strip, guide, test rod, push rod, moving contact piece, static contact piece, spring, screw, reset button, and a setting knob. When the current exceeds the rated value, the mechanism activates, causing the normally closed contact to open or the normally open contact to close. The higher the current, the faster the response. The rated current of the heating element can be adjusted using the setting knob.
When selecting a thermal relay, consider the following:
1. Use a two-phase relay for most applications, but choose a three-phase relay for balanced three-phase motors or those sharing fuses with large motors.
2. The relay’s rated current should be greater than the load's rated current.
3. The heating element’s rated current should be slightly higher than the load’s.
4. The setting current is typically equal to the motor’s rated current. For motors prone to overload, it can be reduced to 60–80% of the rated current. For motors with long starting times or impact loads, the setting current can be increased to 1.1–1.15 times the rated current.
To test a thermal relay:
- Check the heating element resistance, which should be close to 0 Ω. An infinite reading indicates an open circuit.
- Test the normally closed contact: it should have low resistance when inactive and open when activated.
An **intermediate relay** is essentially a voltage relay with multiple contacts that can handle large currents. It is used to switch high-current circuits. Its physical shape often includes inline pins for easy installation. Important parameters like contact configuration and voltage ratings are clearly marked on the relay.
There are several types of **time relays**, including electromagnetic, electronic, and air-damped models. Electromagnetic relays have short delays (0.3–1.6 seconds), while electronic relays offer precise timing (up to 72 hours) and compact designs. Air-damped relays are commonly used for power-on delay applications.
Testing the control coil of a time relay involves checking its resistance. A normal reading should be within the specified range, and any deviation may indicate a fault.
In summary, relays play a crucial role in electrical systems, enabling safe and efficient control of circuits. Understanding their types, functions, and testing methods ensures proper application and maintenance in various industrial and domestic settings.