PROM, PROM
In the early days of the development of the microcomputer, the BIOS was stored in a ROM (Read Only Memory). The internal data of the ROM is burned in a special way in the manufacturing process of the ROM. The contents of the ROM can only be read and cannot be changed. Once it is burned in, the user can only verify whether the written data is correct. No further modifications can be made. If you find any errors in the data, you can only make a copy if you don't use it. ROM is produced on the production line. Due to its high cost, it is generally only used in high-volume applications.
Fundamental:
Due to the inconvenience of ROM manufacturing and upgrading, a PROM (Programmable ROM) was later invented. Initially, there is no data inside the PROM made in the factory. The user can write his own data with a dedicated programmer, but this opportunity is only once. Once it is written, it cannot be modified. If an error occurs, it is written. The chip can only be scrapped. The characteristics of the PROM are the same as those of the ROM, but the cost is higher than that of the ROM, and the speed of writing data is slower than that of the ROM. Generally, it is only suitable for a small number of occasions or for pre-production verification of the ROM.
The EPROM (Erasable Programmable ROM) chip can be repeatedly erased and written, which solves the drawback that the PROM chip can only be written once. The EPROM chip has a very obvious feature. On the ceramic package on the front side, a glass window is opened through which the integrated circuit can be seen. The ultraviolet light can be erased through the hole to illuminate the internal chip. The internal data, the EPROM eraser is used to complete the chip erase operation. The writing of the data in the EPROM requires a dedicated programmer, and a certain programming voltage must be added when writing content to the chip (VPP=12-24V, depending on the chip model). The EPROM model starts with 27, such as 27C020 (8*256K) is a 2M Bits capacity EPROM chip. After writing the data, the EPROM chip also seals the window with an opaque sticker or tape to protect the data from the surrounding ultraviolet rays.
A PVC Insulated Power Cable is a electric cable with flexible copper or aluminum conductor ,PVC insulation and PVC sheath. For some special application like for direct burial or for exposed installation, protective jacket of steel tape or wire is also necessary. The shape of PVC insulated Power Cable may be round or flat. Some PVC cables may select flame retardant material sheath for fire safety consideration.
Product Features
l Widely used to transmit and distribute electrical power in low voltage circuit.
l Choices of conductor& jacket material to suit the requiring applications.
l Armor material options to provide high flexibility and excellent mechanical protection
Using features
l Max. permissible continuous operating temperature of conductor: 70℃.
l Max. temperature of conductor during short-circuit(5s maximum
duration) shall not exceed:
Cross-section of conductor ≤300 square mm: 160℃;
Cross-section of conductor ＞300
square mm: 140℃.
l The ambient temperature under installation should not below 0℃.
Application
l Non-armored type is unable to bear external mechanical force for laying indoors, in tunnel or pipe.
l Steel tape armored (STA) type is able to bear external mechanical force but unable to bear large tension for laying indoors, in tunnel or pipe.
l Steel wire armored (SWA) type is able to bear external mechanical force and certain tension while apply for laying in high drop are.
FAQ
Q: Are you a factory or trading company?
A : We are a manufacturer. We are professional in
developing and producing electrical wires and cables since 2001.
Q: Can I visit your factory?
A :Yes! You are welcome to visit our factory for further detail check.
Our factory is located in Minqing,Fujian.You could choose to fly to Xiamen/Fuzhou International airport. And tell us your flight No. We will arrange to pick you up if you like.
Q: May I buy samples from you?
A: Yes! You are welcome to place sample order to test our superior quality and services.
Q: Can you put my brand name (logo) on these products?
A: Yes! Our factory accepts to print your logo on the products.
Q: May I know the status of my order?
A: Yes .The order information and photos at different production stage of your order will be sent to you and the information will be updated in time.
We would like to offer you professional cable solutions to your particular requirement. And OEM service is available based on official and legal authorization. Please do not hesitate to contact us for more details.
PVC Insulated And Sheathed Power Cable
PVC Insulated And Sheathed Power Cable,Insulating Electric Power Cables,PVC Sheathed Power Cables,Al PVC Jacket Electric Cable
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