Hello, welcome to visit the official website of zhongshan xiaolan guoke relay factory.Service phone:0760-22131558！
0760-87760698
| Attention should be paid to the environmental selection of automobile relays | ||||
| Publisher:admin | Add time：2018/10/30 | Viewed：676 | ||
| The following environmental parameters should be taken into consideration when selecting relay: temperature 1) under high temperature conditions, insulation materials will soften and melt; Under low temperature condition, the material cracks, the insulation resistance performance drops, so that failure. But the engineering plastics with excellent performance can meet the requirement. 2) under the alternating action of high and low temperature, the structure becomes loose and the position of the moving parts changes, which leads to out-of-control suction and release and poor or no contact. 3) at low temperature, water vapor condenses and freezes inside the relay, resulting in decreased insulation performance. 4) under high temperature conditions, coil resistance increases, and the pull-up voltage increases accordingly, resulting in no pull-up or quasi-suction and non-suction, leading to relay failure. Damp-heat and damp-heat pose a threat to the performance of the relay, as follows: 1) long-term damp-heat will directly lead to the decrease of insulation resistance level, resulting in complete failure. Especially, the insulation failure of relay will be caused by humidity and heat after it is polluted by sand and dust during long-term naked storage or operation. 2) under the condition of humidity and heat, the coil is broken due to electrochemical corrosion or mildew, and the contact electrochemical corrosion and oxidation aggravate; The corrosion speed of metal parts increases significantly, the performance of the relay becomes worse, and the working reliability becomes worse, resulting in complete failure. 3) under wet and hot conditions, when the contact is charged to switch the load, the arc pull phenomenon intensifies, resulting in shortening the electric life. In tropical, subtropical electronic products, product design, material selection must fully consider the problem of humidity and heat. The failure of relay caused by sand dust pollution has not attracted enough attention of users. In the natural environment or the general industrial workshop environment, especially the electronic devices used in cars, sand dust often infiltrates into the relay through the heat dissipation holes and cracks. After accumulation and starting up for inspection, dirt dust accumulation can be found, causing the moving parts to turn (slide) dead; Electric contact failure of contact; Under the action of humidity, the corrosion of metal parts intensifies, and the insulation performance of insulation parts declines, leading to failure. Some relays for electric power protection and automobile relays have passed the inspection before delivery. After one or two years of operation, the relays are constantly in trouble. The hazards of dust pollution must be fully considered when designing and using. Users make specific requirements according to practical needs. Chemical atmosphere pollutes the environment. Organic vapors, oxygen, sulfur dioxide, salt fog, etc. in the atmosphere have corrosive effects on relay contacts, metal parts, coil and insulating parts, resulting in poor electrical contact of the contact and failure. Leading coil lead rusting broken wire, lower insulation level. Chemical harmful gases are common in nature, but there are different types of harmful gases (steam) on different occasions. Process measures can mitigate and avoid erosion, but the cost will rise greatly. For example, the leakage rate of military sealed relay can be up to 10-8pa.c m3/s through long-term high temperature vacuum baking, high pure N2 filled in the relay cavity and sealed welding by electron beam (or laser). ; The contact is plated with 1 ~ 3u gold. Civil relays are limited by the price, which generally only add the plastic enclosure to alleviate the erosion of harmful gas (steam) in the atmosphere. When used, according to the load of the relay and the environmental advantages and disadvantages, the process holes can be opened at your discretion to improve the heat dissipation capacity and reduce the pollution of the contact surface by the organic steam and sulfur dioxide inside. Mechanical vibration relay will encounter vibration of a certain frequency range and acceleration value in the vicinity of strong power equipment and during transportation. The in-flight vibration can represent the field vibration stress of missiles, high-thrust jets and rocket engines. The influence of vibration on relay is shown in the following aspects: a. vibration may cause looseness, fatigue and fracture failure of mechanical structural parts; B. The closed contact fails due to instantaneous disconnection caused by vibration greater than the standard time; C. The breaking contact fails due to the instantaneous closure caused by vibration greater than the standard specified time; D. Causing relative motion between moving parts, resulting in noise, wear and other physical failures. The impact relay is often affected by mechanical impact in transportation, transportation and use. The impact of impact on the relay is as follows: 1) due to impact, the structure becomes loose, damaged and fractured, and the ability to work is lost. 2) the closed contact fails due to an instantaneous break greater than the specified requirement due to impact; The break contact produces an instant closure larger than the specified requirement and fails. Therefore, for (1), it is required that the relay should have the performance of impact strength, and the measured results of the specified items before and after the test should meet the requirements of product standards. For (2), the relay shall have the performance of anti-impact stability, and the contact state of the contact shall be dynamically monitored. | ||||
RichScan
RichScan