(1) system automatic detection
The sewing machine electrical control system generally has the capability to automatically detect failures with intelligence, depending on the different alarm codes of the system, to determine what malfunctions occur in the system and to further determine which part of the system is problematic. The failure code could be identified and maintained in a corresponding processing method, and different brands of electrical control systems may use different fail codes, but the type of failure is not different and the machine's instructions are marked with notes, as detailed in the relevant sections below。
(2) direct observation
Direct observation is the most basic method of repair inspection, mainly by which repair technicians, by means of visual, sniffing and tactile observation of the machine, compare with the normal working conditions of the system, thereby reducing the range of malfunctions or directly locating them. For example, there are no marks on the surface of the observation controller and display screen, no drops of the plugs, no break in the lead line, no burn-up of the electrocution circuit board units, no foot break, no foot contact。
(3) substitution
The replacement method is the most efficient method of repair and inspection to reduce the range of malfunctions, which is the determination of the fault area or malfunctioning element through the replacement of a suitable component. Repairs often begin with large components and are replaced and removed step by step until failure is detected. This method is used mainly where the spare parts are sufficient or other well-functioning electrical control systems are available for conversion. For example, the maintenance of the communications server system involves a determination as to whether it is a system problem or not, and the question of distinguishing between sewing machines or control boxes is generally addressed by switching the normal control box. This method is also used in the maintenance of circuit boards to determine the location of the malfunction using the known good meta-ware replacement device, which is suspected in the circuit, to observe changes in the controller。
(4) measurement of voltage
The working voltage at each point of the machine during normal working hours of the exchange server indicates the working condition of the machine within a certain range, and the working voltage changes when a malfunction occurs. The method of measuring voltage is to test the work voltage of the various plugs in the machine and at the test points of the circuit board with a universal meter to determine the cause of the failure in the light of the abnormality of the voltage. Interchange voltage and direct current voltage are measured at a range of scales. The measure of voltage is often measured with the machine carrying the charge, so one-hand operation is the first to be safe. For example, the failure to respond to the switch on the electrical system requires a step-by-step measurement from switch to circuit board, in case of electrical upkeep, until the breakpoint is identified。
(5) measurement of electrical resistance
The method of measuring resistance is the determination of the specific cause of failure through the pass-through and break-up of the om slot detection line and the size of the resistance. In the absence of electricity, some of the lines are connected, some of them open, and some of them have electrical resistance values that change in the state of resistance when the work is irregular, and are detected by measuring the resistance and judging the parts of the failure in the light of the change. Remembering to measure resistance is usually performed without electricity in the controller. For example, electromagnetics are detected by measuring their resistance within normal limits through the om array。
(6) measurement of currents
The measurement of currents is the measurement of faults by measuring the size of the working current at a point in the controller. In the survey, the original line is to be disconnected and then restored after the check. The current measurement is more cumbersome than the voltage measurement operation, so it should be the first option to measure the voltage method, followed by current measurement if necessary。
(7) open road inspection
The open-circuit inspection method is to cut off a functional circuit in the control system and observe the performance of the control system to reduce the failure range. For example, failure alarms for electromagnetic functions in electrical control systems can be determined by disconnecting the electromagnetic interface or further disconnecting the electrical voltage of the electromagnetic magnet。
