How To Check The Rotor Angle Grinder

Checking and repairing the armature angle grinder with your own hands 1. Checking the stator and rotor of power tools for inter-turn circuit

It does not take much time to check the stator and rotor for turn-to-turn circuit with a multimeter. It will take longer to disassemble the engine. Angle grinder, drill, hammer drill. Each tool can be repaired, having identified a malfunction. It is better to break the check into several main stages, and consistently slowly perform the actions.

Visual inspection

Even with a full arsenal of instruments for testing the electrical circuit of the armature, never do not neglect visual inspection. A mandatory first step in the entire diagnostic process. A careful glance will find signs by which a user who knows the design and principles of the rotor will determine the nature of the faults.

Charred traces and the presence of a specific odor are the cause of burnt insulation and ultimately damage to the winding wires. Attention should be paid on crumpled or swollen turns, which can authorize the presence of breaks in this place. The windings may contain solder particles, which are the source of the short circuit.

Violations of the contacts of the windings with the collector can be detected on burned-out lamellas. Damage to the collector itself is visually diagnosed. Raised, worn or burnt plates.

Testing and diagnostics methods

How to check if the angle grinder rotor is working properly? It is simply necessary to check the place of engine breakdown in case of its malfunction. After all, it is this procedure that will help to understand which part of the mechanism is working and which is no longer. Diagnostics is carried out in several ways:

• Visual;
• Using a multimeter;
• A light bulb;
• Special devices.

Sometimes even a visual inspection is enough to understand that a short circuit has occurred. In this case, the details will show, for example, an unprotected winding, wires where the insulation will be melted. You should also pay attention to charred varnish or its smell after engine overheating.

Loss of contact also occurs due to the collection of dust (graphite from brushes) on the lamellas. It is not difficult to notice it, as well as to clean the anchor from such fine debris.

A device called a “multimeter” also helps to establish a breakdown of an electrical device. It is enough to set the resistance to 200 Ohm and put the probes on two adjacent lamellas. The resistance between all the plates will be the same during the normal functioning of the part. If the indicator is less than 1 Ohm, then the matter is in the closure of the turns. When the indicator is more than one, this means a break in the winding turns. The device can even go off scale, since the resistance in the latter case can be very high. Using an analog multimeter, the arrow will swing to the right to the very end, the digital measuring device will not show anything.

A multimeter is, in fact, the same tester that determines the resistance in the right places of power tools.

When there is no device for determining and calculating resistance, you can use a simple 12 volt 40 W light bulb. Connect two wires to the light bulb. Where there is a minus, you need to make a break. Next, we apply voltage. We apply the ends of the wire at the break to the collector plates and scroll it. When, with such manipulation, the light is on without changing the brightness, then there is no short circuit.

Another test method concerns the breakdown of the current to ground. To do this, we connect one wire with the lamellas, and the second with the iron of the armature. After we carry out the same manipulation with the shaft. In the event of a malfunction in the part, the light will glow.

In any of the ways, you can check the stator of the angle grinder, which can also be the cause of breakdown or heating of the motor.

How to check the serviceability, ring the rotor of the angle grinder at home,

In a domestic environment, there are the following methods for diagnosing an anchor:

• Visual inspection;
• Using a multimeter;
• A light bulb and two wires connected to it;
• Devices specially designed for checking the integrity of the windings (short-circuit indicator, armature checking device and others).

details about the types of diagnostics in the following information, where there is.

Multimeter application

Now you need to check the possibility of breaking the stator windings. On the scale of the multimeter, set the switch to the resistance measurement sector. Without knowing the value of the measurement, we set the maximum value of the value for your device. Checking the tester’s performance.

We touch each other with the probes. The arrow of the device should show 0. We carry out work, touching the terminals of the windings. When an infinite value is displayed on the scale of the multimeter, the winding is faulty and the stator should be rewound.

We check the possibility of a short circuit to the case. Such a malfunction will cause a decrease in the power of the angle grinder, the possibility of electric shock and an increase in temperature during operation. The work is carried out in the same way. We turn on the resistance measurement on the scale.

Place the red probe on the winding terminal, attach the black probe to the stator housing. If the winding is short-circuited to the case on the tester’s scale, the resistance value will be less than on a good one. This fault requires rewinding of the stator windings.

It’s time to take measurements and check if there is an interturn short circuit in the stator winding. For this, the resistance value is measured on each winding.

We determine the zero point of the windings by measuring the resistance for each of them. When the instrument shows the lowest winding resistance, it should be changed.

Checking the performance of the anchor angle grinder

The angle grinder anchor is more strongly exposed to various electromagnetic, mechanical and thermal influences than other units, therefore it is the rotor that is most often the reason for the failure of the tool.

How to check an anchor on an angle grinder with improvised tools:

• A breakdown of the armature assumes two variants of malfunctions: breakage of current conductors on the lamella contacts, short interturn circuit in one or more windings. An electrician’s tester in the resistance measurement mode up to 200 Ohm makes it possible to detect breaks and complete short-circuiting of the winding (it will show an immensely low resistance), and in the resistance measurement mode of the order of 1 MΩ, the reliability of the electrical insulation of the windings of the working coils to the metal body of the rotor is checked.
• The absence of a pronounced short-circuit in the armature windings does not completely disable the tool, but there is an increased heating of the engine, a decrease in its speed, which will eventually lead to a complete engine failure. Therefore, in any tool repair, it is imperative to ring the anchor of the angle grinder not only with a tester, but also check with a specialized device that detects even minor short circuits.

Electric part breakage angle grinder

Failures of electrical failure of the angle grinder can be divided into just two categories:

1. Mechanical rupture of current conductors, which can be detected in the lead wires, switch buttons and contact points of the working windings. To determine the absence of breaks, an electrician’s device “multimeter” in resistance measurement mode or an ohmmeter is used. All electrical sections are checked separately: supply to the electric motor, connections at the contacts of the stator and rotor windings.
2. Electrical breakdown of working coils, which can be detected by darkening of the conductors, and can be visually hidden. In any case, you will have to check the armature and stator for an angle grinder with a tester for the absence of short-circuited turns, which may not always be effective, and for accurate diagnosis you will need a specialized device.

How to check the rotor of an angle grinder

The use of an angle grinder in everyday life is ubiquitous, and due to the difficult operating conditions of frequent use, the failure of the device is not uncommon. Tool repair most often consists in diagnosing failing units and replacing them or carrying out recovery measures. If mechanical breakdowns and increased output of the gear transmission are easily visually detected, then in order to check the armature and stator of the angle grinder, specialized knowledge, skills and technical devices are required.

Stator performance check

How to check the stator of an angle grinder with improvised means:

• The stator can have two main failures. A break in the conductor or the occurrence of short-circuited turns. At the same time, checking with a tester in the resistance measurement mode up to 200 Ohm is able to show only the absence of breaks with averaged resistance values, which should not differ between the phase windings.
• The absence of breaks in the stator windings can be determined with any low-voltage probe: a pair of wires, a battery, a light bulb. But, the presence of a short circuit in the circuit cannot be detected in this way, therefore, experienced electricians check experimentally: voltage is applied to the phase coils, while a metal ball is placed in the center between the poles of the windings, which, with normal windings, will “search” for the point of electromagnetic balance. The rotation of the ball indicates the absence of a short circuit in the coils, the offset from the center indicates a short circuit in the conductors on the opposite side.

• The stator of the angle grinder can be checked safely and accurately only with a professional device.

Repair or replacement of electrical components angle grinder

When repairing a power tool, you must clearly understand how to properly check the armature and stator of the angle grinder:

• The tester allows you to measure the resistance of the windings and detect breaks in current conductors, therefore, even compliance with the table readings does not guarantee the device’s performance, but only indicates gross mechanical failures.
• Checking the short-circuited turns in the coils is carried out by professional or home-made devices that measure the changes in the inductance of each working winding, because Short circuit reduces the level of EMF.
• When repairing a tool, it is often found that outwardly all the windings are intact, but they have short circuits. The operation of such a tool is unsafe, so the question arises about the need to rewind the stator, rotor or replace the “punched” bridle.
• Practice shows that restoration measures (rewinding), even in a repair shop, do not guarantee long-term reliable operation of the device, therefore it is recommended not to take risks, but to immediately install spare parts from the manufacturer.