Views:38 Author:Site Editor Publish Time: 2017-04-04 Origin:Site
1. Fault investigation before examination
When the industrial machinery electrical fault happened, we should not hands-on maintenance blindly. First of all, please ask the personnel when the fault occurred or CNC lathe machine operator. Make sure it is the first time suddenly, or often occur, the occurrence of parts, external phenomena such as smoke, flashover, abnormal sound, the surrounding environment, Gas, corrosive gas corrosion, whether the water leakage, heat damage caused by electrical etc .; whether there is someone already repaired, the repairing contents of what operations and malfunctions.
Because the CNC lathe machine operators are most familiar with the performance of the CNC lathe machine, but also better understand the possible causes of failure and location firstly, it is helpful for CNC lathe machine maintenance personnel to determine the scope of failure and analysis of fault causes.
Before the repairing, we should understand the operation before and after the failure and the occurrence of abnormal phenomena by asking, watching, listening, touch to, in order to determine the fault occurred according to the location of the fault, and then accurately troubleshooting.
Q: Ask the operator before and after the failure of the circuit and the operation of the equipment and the symptoms after the failure, whether the fault is frequent or occasional; whether there is noise, smoke, sparks, abnormal vibration and other signs;
Listen: if the line can run and do not damage the equipment, we could do power test, listen to the motor contactors and relays and other electrical sound is normal.
Touch: just cut off the power, as soon as possible to check the motor, transformer, solenoid and fuses, etc., to see if there is overheating.
Through the above investigation, we could have a preliminary understanding about the phenomenon of the fault, which reflects a variety of fault problems, and fault phenomena and fault types are mach each other, as long as the phenomenon can be seized by the signs, it is not difficult to find the fault.
2. Determine and reduce the scope of the fault for electrical apparatus of CNC lathe
with logic analysis
According to understanding the phenomenon of fault, we could further classify electrical fault, thus have a clear breakdown of the scope of the motor part, the main circuit part, or part of the control circuit failure, or control the electrical component itself failure.
3. Find the fault point of electrical apparatus of CNC lathe machine according to the fault range
After determining the possible range of the occurrence of the fault, it is necessary to further determine the point of failure, to find the point of failure, we must apply the correct and effective method.
3.1 Perform a visual inspection of the fault range
After determining the possible range of the occurrence of the fault, we will have an appearance of the electrical components and connecting wires for visual inspection, such as fuse melt blow, wire connector loose or fall off, contactor and relay contacts fall off or bad contact, the coil is burned to make the surface insulation paper charred discoloration, burning insulation varnish out, spring off or broken; electrical switch action mechanism obstruction failure, etc.. These can clearly indicate the point of fault.
3.2. Determine the point of failure FOR of electrical apparatus of CNC lathe machine with the power testing method. If we haven’t find fault through appearance inspection , we could according to the phenomenon of fault, combined with the circuit diagram analysis of the cause of failure to confirm the fault, of course based on the premise that will not further expanding and causing personal and equipment accidents.In order to understand the possible reasons more accurately, we could check (if necessary, remove the load connection) to distinguish the fault may be in the electrical part or in other parts of the machine; is it on the motor or in the control device; is it in the main circuit or in the control circuit. Normally we could check the control circuit; the specific approach is that the operation of a button or switch, the line of the contactor, the relay will work in accordance with the provisions of the order. If the action to an electrical device in turn does not meet the requirements, it means both the electrical components and its related circuit has something wrong. And then check and analyze on one by one, we could find the fault. After the control circuit is restored to normal, please check the main circuit and observe the work of the main circuit is so on.
3.3 Determine the point of failure according to the fault range
When the fault range is in a certain part, the instrument, instrument and corresponding detection method will further reduce the fault from the larger range, and finally determine the point of failure.