485 232 Thermally Sensitive Resistor 30-60 Ohm PTC Positive Temperature Coefficient Thermistor MZ11-10A300-600RM

Description

MZ11-06A300-600RM and MZ11-10A300-600RM PTC thermistors are developed from the program-controlled security unit used in program-controlled switches. They are protective components used in 485 communication interfaces. This product is connected in series in the 485 communication interface to effectively prevent the interface from being damaged by the 220V mains electricity introduced due to accidental damage or human damage to the communication line, and can also appropriately reduce the impact of lightning induction on the interface.

Working Principle

This product has the characteristics of small steady-state resistance, low rated current, high withstand voltage, and fast response speed. It is an economical and applicable choice for realizing 485 communication interface protection. Its application principle is shown in the figure below: Under normal communication state, this product is equivalent to a current limiting resistor connected in series in the line, and the resistance value does not change. In abnormal situation, overvoltage will cause the TVS tube to be broken down, and the voltage will be clamped to protect the 485 communication interface. At this time, a large current passes through the PTC thermistor, causing its resistance to show a step change, rising by 4-5 orders of magnitude and presenting a high resistance state, achieving the purpose of protection. After the overvoltage disappears, the PTC thermistor will return to its original state without affecting the communication function.

Specification

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