Failure and maintenance of laser grader
he substitution method uses devices that have been identified as the best devices to replace suspected devices and gradually narrow the search area.3. comparison method"Comparative law" is the correct feature (or voltage waveform) characteristics and fault machine (or voltage waveform) are compared, waveform or voltage which component does not match, according to the logic circuit by measuring the signal from the pole, the pursuit of the direction of the source point detection and analysis to determine the fault location.4. measurementMeasuring method, also called static measurement, is to try to pause the computer in a certain state. According to the logic diagram, the meter is used to measure the required level and to analyze and judge the fault.5. liter temperature method"Ascending temperature method" is to artificially raise the environmental temperature, to accelerate some of the high temperature parameters of the poor components "death" to find fault.6. beat methodWhen the machine is running good or bad, may be the cause of the pin component element can weld or poor contact or metal through hole resistance increases the. In this case, the available on inspection method, tapped on the circuit board with a rubber hammer, and then check more easily.
Method for checking hardware faultFor the soft failure of the computer, it can be solved by analyzing the fault phenomena, reloading the system, replacing the software, modifying the software program, or clearing the computer virus. And for hard failure, it is necessary to check and eliminate step by step according to the inspection principle. The following ten kinds of hard fault inspection and judgment methods are introduced:1. plug methodThe "plug" is the plug-in "draw" or "insert" to find fault method. For example, the machine "deadlock" phenomenon, using this method to pull out the plug-in board one by one, and if the machine returned to normal, indicating that the fault is on the board.2. substitution methodT
7. division methodThe segmentation method is the method of "fault segmentation", which gradually reduces the size of a piece of board and shrinks to a certain line and then to a certain point.8. direct observationDirect observation method is the use of human senses, the phenomenon of direct observation of spark, abnormal sound, overheat and burn, make sure that the power supply short circuit, overcurrent, overvoltage and plug loose components, corrosion damage and obvious fault.9. isolation compression methodThat is, according to the fault phenomena and the hardware components, some information about the parts is temporarily disconnected, or simplified raw data is used to reduce the search scope.10. program testingThat is to help search failure by using the power on self-test program and senior special diagnostic procedures, diagnostic procedures provide a number of measuring hard drive, floppy drive, CD - ROM and printer detection by the menu form, if the hardware failure display the error and noise so as to obtain the fault point and its causes.
