Hose crimping machine is connected to electrical circuit electrical components. So the hose crimping machine own electrical parameter is a hose crimping machine should first consider the question. Proper selection and use of hose crimping machine is to ensure the reliability of the circuit is an important aspect.
Introduction
Hose crimping machine (hose crimping machine ) also can be called a plug seat, widely used in various electric circuit, a connecting or disconnecting circuit function. Improvement of hose crimping machine reliability is first manufacturer responsibility. But because the hose crimping machine variety, a wide range of applications, therefore, choose the right hose crimping machine hose crimping machine is also improving reliability is an important aspect. Only through the joint efforts of both sides to manufacturers and users, can play a maximum of hose crimping machine due function.
Hose crimping machine have different classification methods. According to the frequency division, have a high frequency of hose crimping machine and hose crimping machine low frequency; according to the shape with rounded rectangle with the machine; even the machine, according to the use of a printed circuit board, with hose crimping machine, hose crimping machine cabinets, audio equipment with hose crimping machine, hose crimping machine power, special use hose crimping machine. The following discusses hose crimping machine ( low frequency below 3MHZ ) selection method.
The requirement of electric parameters
Hose crimping machine is connected to electrical circuit electrical components. So the hose crimping machine own electrical parameter is a hose crimping machine should first consider the question.
Rated voltage
Rated voltage called working voltage, it mainly depends on even the machine used by the insulating materials, contact between the pair of spaced size. Some element or device below its rated voltage, may not perform its function. Hose crimping machine rated voltage in fact should be interpreted as the manufacturer recommends a maximum working voltage. In principle, the hose crimping machine in less than the rated voltage can work normally. The author according to the hose crimping machine tend to withstand voltage ( dielectric strength ) index, according to the use environment, security requirements to a reasonable selection of rated voltage. That is to say, the same pressure index, according to the different use of the environment and safety requirements, can be applied to different maximum working voltage. This is consistent with the objective situation.
Rated current
Rated current and working current. With the rated voltage, rated current in lower case, hose crimping machine can work normally. In the hose crimping machine design process, is based on the hose crimping machine thermal design to meet the requirement of the rated current, because is in contact with the current flows, due to the presence of the conductor resistance and contact resistance, contact will heat. When the heating exceeds certain limit, will damage the hose crimping machine insulation and forming a contact on the surface coating of softening, caused by a fault. Therefore, to limit the rated current, in fact to limit the hose crimping machine internal temperature rise not to exceed the specified value design. Choose to pay attention to the question is: for multi core hose crimping machine, rated current must be derated to use. In the current situation should be attached great importance, such as diameter of 3.5mm exposure on general provisions, the rated current of50A, but in 5core to derating33%, namely every core current rating of only 38A, core number, derating the larger amplitude. Derating amplitude can refer to table 1
Contact resistance
Contact resistance refers to the two contact conductor in contact resistance. In the selection of should pay attention to two issues, first, hose crimping machine contact resistance index is in fact contact resistance, which comprises a contact resistance and contact resistance of a conductor. Usually the conductor resistance is small, so the contact resistance in many technical specification known as the contact resistance. In second, connecting the small signal circuit, attention should be paid to give contact resistance index is under what conditions test, because the contact surface will annex the oxide layer, oil or other contaminants, the two contact surface will produce a film resistor. In the film thickness increases, the resistance increases quickly, is a film become poor conductor. However, the film in high contact pressure occurs under the mechanical breakdown, or in a high voltage, high current occurs under the electrical breakdown. For some small volume of the hose crimping machine design of the contact pressure is quite small, the use of occasions only mA and mV film resistance, not easy to be broken down, may influence the transmission of electrical signal. In GB5095" in the electric equipment with mechanical and electrical components - Basic test procedures and measuring method of contact resistance test method for" one" -- no contact resistance executed" provisions, in order to prevent the contact insulating film is breakdown, test circuit open-circuit EMF DC or AC peak value should be less than 20mV, DC or AC current test should be not more than 100mA. In fact this is a low level contact resistance test method, therefore, the requirements of the selection, as selected by the low level contact resistance index of hose crimping machine.
Shielding
In the modern electrical and electronic equipment, components of the density and their related function is increasing day by day, on EMI put strict limits. So the hose crimping machine often use metal shell is closed, to prevent the internal electromagnetic energy or by external electromagnetic interference. At low frequencies, only magnetic materials magnetic field shielding effect to obviously. At this time, the metal shell of the electric continuity have certain provisions, namely housing contact resistance.
Safety parameter
Insulation resistance
The insulation resistance is defined in hose crimping machine insulation voltage is applied, so that the insulating part in or on the surface of producing leakage current exhibit resistance value. It is mainly affected by the insulation material, temperature, humidity, fouling factors. Hose crimping machine samples are provided on the insulation resistance is generally in standard atmospheric conditions index value, in certain conditions, the value of insulation resistance and there will be no need to decrease. In addition to the attention of the insulation resistance of the test voltage value. According to the insulation resistance ( M omega ) = with the insulator leakage current voltage ( V ) / ( A ) by applying different voltage, there is no results. In the hose crimping machine experiment, the applied voltage is10V,100V,500V third.
Withstand voltage
Contact pressure is of mutual insulating portion or between the insulation and earthing, within the specified time can bear higher than the rated voltage without breakdown threshold voltage. It is mainly affected by exposure to distance and the creepage distances and geometries, insulator material and the environmental temperature and humidity, the effects of atmospheric pressure.
Combustion of
Any of the hose crimping machine at work are inseparable from the current, there is the danger of fire. So the hose crimping machine not only can prevent the ignition, also ask at once ignition and fire, in a short period of time to suicide. In the selection we should pay attention to selecting and using fire retardant, self-extinguishing insulating materials electrical hose crimping machine.
Mechanical parameters
Single leg separation force and total separation force
Hose crimping machine contact pressure is an important index, which directly affects the size and contact contact resistance to abrasion. In most structures, direct measurement of contact pressure is quite difficult. Therefore, often through the single leg separation force to indirect measurement of contact pressure. For the circular pinhole contact pair, usually with a specified weight weight standard pin to examine female contact piece holding weight capacity, generally the standard pin diameter is the male contact diameter lower take5m. Total separation force is generally a single leg separation force line and two times. Total separation force than 50N, artificial plug has been quite difficult. Of course, some of the test equipment or some special requirements of the occasion, can choose zero insertion force hose crimping machine, hose crimping machine automatically fall off.
Mechanical life
Hose crimping machine mechanical life refers to plug life, usually for 500~ 1000 times. In the predetermined mechanical life, hose crimping machine contact resistance, insulation resistance and dielectric index should not exceed the specified value. Strictly speaking, now the mechanical life is a kind of fuzzy concept. Mechanical life should have a certain relationship with the time,10 years after500and1 years out of500, obviously it is not the case. But there is not a more economic, more scientific method to measure.
Contact number and pinhole
The preferred according to the circuit needs to choose exposure on the number, at the same time to consider the hose crimping machine volume and total separation force. Contact log orders, of course its volume is large, the total separation force is relatively large. In some high reliability requirements, and the volume is allowed under the circumstances, can be used to contact on the two parallel method to enhance the reliability of the connection.
Hose crimping machine plug, socket, the pin ( male contact elements ) and Jack ( female contact elements ) are generally interchangeable assembly. In practical use, according to the plug and the socket are charged to select. Such as a socket needs to be charged, optional mounted jack socket, because with jack socket, the electrical contact is buried in the insulator, the human body is not easy to touch the charged contact, relatively safe.
Vibration, shock, collision
Hose crimping machine is mainly considered in a prescribed frequency and acceleration under the condition of vibration, shock, collision contact for electrical continuity. Exposure to this dynamic stress occurs the phenomenon of transient circuit. Provisions of the wink break time is1 ~ s,10 ~ s,100 ~ s,1ms and 10ms. To note is how to determine the contact on the occurrence of transient fault. It is now generally accepted that, when the closed contact ( contact ) on both ends of the electromotive force voltage drop over50%, can determine closed contact ( contact ) failure. That is to say whether intermittent disconnection with two conditions: duration and voltage drop, both are indispensable.
Connection mode
Hose crimping machine generally comprising a plug and a socket, wherein the free end plug is also known as hose crimping machine, hose crimping machine socket fixed. Through the plug, socket and inserting and separation to realize circuit connection and disconnection, so producing the plugs and sockets of various connectivity patterns. On circular hose crimping machine, are in screw thread connection, the bayonet type connection and pin type connection in three ways. One of the most common type of thread connection, it has simple processing technology, low manufacturing cost, wide application range and the like, but a slow connection is not suitable for frequent insertion and rapid successive occasions. The bayonet type connection due to three bayonet lead longer, therefore the connection speed is fast, but it is more complex, the cost is higher. Cylinder type connection is a three connecting means connecting the fastest one, it need not only rotary motion, linear motion can realize the connection, separation and locking function. Because it belongs to the direct push pull type connection mode, so only applies to the total separation force is not hose crimping machine. Generally in small hose crimping machine in the more common.
Installation and configuration
Hose crimping machine installation is installed before and after installation, fixed mode, screw, rivet collar or hose crimping machine itself fast locking pin. There is also a plug and socket are hose crimping machine is a free end, the so-called hose crimping machine relay.
Hose crimping machine shape the myriads of changes, the user is mainly from the straight, curved, wire or cable outer diameter and shell fixing requirements, volume, weight, whether need to connect metal hoses and other aspects of selection, in the panel on the use of the hose crimping machine but also from the appearance, shape, color and other aspects of selection.
Environment parameters
Environmental parameters mainly include the environmental temperature, humidity, temperature, atmospheric pressure and blastic corrosion environment. Hose crimping machine in use and storage, transport processes in the environment on the performance of a significant impact, so must be based on the actual environmental conditions to select the corresponding hose crimping machine.
Ambient temperature
Hose crimping machine metal material and insulation material determines the hose crimping machine working environment temperature. High temperature will destroy the insulation material, insulation resistance and dielectric properties caused by reduced; on metal, high temperature can make contact to the loss of elasticity, accelerated oxidation and coating modification. Usually the environmental temperature of - 55~ 100special circumstances may require higher.
Wet
Relative humidity is greater than 80%, is the cause of breakdown reason. Humid environment caused by water vapor in the insulator surface diffusion and absorption, easy to reduce insulation resistance to M ohm level below, in the high
