Electrical equipment fault diagnosis & quot;
Six diagnosis & quot;
Method one, 'six' asked mouth, eyes, ears to hear, nose to smell and table six diagnostic methods, fingerprint, simply put is through the 'ask,' see, hear, smell, touch, test to find out the abnormal situation of electric equipment, so as to find out the cause of the problem and the problems of parts.
Before the 'five diagnosis' by human senses targeted on electrical equipment fault diagnosis, called sensory diagnosis, also known as intuitive method.
Also, due to the individual difference of technical experience, the diagnosis is also different.
'People consultation method' can be used for the correct conclusion.
'Table' measurement is applied electrical instrument measuring some electrical parameters, the size of the after compared with the normal numerical value, to determine the cause of the problem and the location.
1, mouth asked when a device of the electrical system failure, maintenance staff with doctors, first of all to understand the details of the 'condition'.
To equipment operators or users understand the medical records of the equipment usage, and the whole process of failure.
If a fault occurs in the during or after operation, but should also ask the time of the operation contents and methods, steps.
In general, know the situation as far as possible detailed and true, these are often the key to quickly find out the cause of the problem and the location.
2, see (1), look at the site according to asked about the situation, take a closer look at external equipment or operating conditions.
Such as the appearance of the equipment, color without exception, fuse with and without fusing: electric circuits of the presence of burning, burning, open circuit, short circuit, mechanical part is damaged and switch, knife switches, button wiring the location are correct, but the connection with and without errors, consistent whether replacement of components such as: to observe the signal display and instrument, etc.
(2), watch must carefully check drawings and data related to the failure of electrical principle diagram and the installation wiring diagram, should first read schematic diagram, then look at the wiring diagram, guide 'practice' to 'theory'.
Understand familiar with relevant fault equipment electrical principle diagram, analyze the problems have that part and the control circuit, the electrical components, produce the phenomenon can be described what's wrong with it.
Then, based on the analysis of decided to check those places, and gradually down to find fault.
3, ear listens sound of electrical equipment operation.
Electrical equipment will have some noise in the running, but its noise is uniform and has a certain regularity, general noise intensity is low.
Belt to run in spite of the electrical equipment of the noise is usually change, listen with the ear often can be the difference between it and normal equipment operation is the difference of noise.
Using auditory judgment fault, although is a complex work.
But as long as the spirit of 'seeking truth from facts' of the scientific attitude, from set out actually, is good at error rule, scientific analysis, can diagnose the causes of electrical equipment and parts.
Sound is due to the vibration and the object, if found out the regularity of voice, can see through it to see not the cause of the problem.
Such as the influencing factors of motor noise are: (1) temperature.
Some noise is increased with the temperature and motor or enhanced, and decreases with the increase of temperature and some sound or disappear.
(2) the load.
Load has a great influence on the sound is loud and enhance with the increase of load, it is the general rule of sound.
(3) the lubrication.
No matter what noise, when the poor lubrication condition, usually seriously ring.
(4) auscultation apparatus.
Available with a screwdriver, metal rod, thin metal tube, etc. , by auscultation appliances touch the test points, noise, and to facilitate diagnosis.
With sound auscultation appliances direct contact in site auscultation, called 'solid', separated by a distance with ears auscultation, called 'virtual listening ', two methods should be used.
In daily production to accumulate rich experience, can play a role in practical application.
4 use people's sense of smell, nose to smell, according to the smell of the electrical equipment failure.
Breakdown fault, such as overheating, short circuit, it could smell burning, smoke and fire such as plastic, rubber, paint, lubricating oil is heated.
For filling equipment, internal short circuit, overheating after water be affected with damp be affected with damp, the smell of the sample will also change, such as acidity.
5 with the hand touch, fingerprint equipment on site, according to the temperature and vibration fault.
If equipment overload, its overall temperature will rise, such as local short circuit or mechanical friction, may appear local overheating 'such as mechanical jam or balance is not good, its amplitude will increase.
In addition, the practice also should pay attention to comply with the safety rules and characteristics of the equipment, to master touch (
Methods and techniques, the touch touch, can't touch the cut groped.
Hand print the strength should be appropriate, lest endanger personal safety and equipment damage.
6, table with measurement instrument inspection on electric equipment.
According to the size of the instrument measuring some parameters, after compared with the normal data to determine the cause of the problem and the location.