To test inter-turn short-circuit, use an ohmmeter. Connect the device and take readings. Verify the results with a given resistance value. Remember that by reducing the winding resistance through the contacts of the regulator begins to pass current greater permissible value (often between the contacts skips spark).Please note, if the power generator has fallen sharply, the battery is stopped to show the level of charge, then most likely there is a break in the circuit phase windings of the stator. If you broke both phases, the generator will not work at all.
If you have already disassembled the generator, test the inter-turn short circuit can alternately connecting to the battery phases, closed on the bulb. The lamp will not illuminate if the circuit is open.
Use flaw PDO-1 this unit has an induction and receiving-signal devices. When checking the winding flaw install so that the groove between the teeth of the stator core located between the air gaps of the core and receiving the signal and induction machines. Connect the induction coil of the apparatus to the source of AC or DC voltage of 12 V. In case of a malfunction of the circuit, a neon lamp PDO-1 will be steadily lit.Remember that the detector can work continuously for not more than three minutes.
Use the electromagnet and the steel plate. The method is simple and old, but has not lost its effectiveness. Place the steel plate on the reel but fix it if you have closed coils, the plate will be attracted to the grooves where the damaged section.
Advice 2: How to determine winding short circuit
In the coils the field coils can sometimes happen interturn short circuit. The reason for this faulty coils is mechanical damage or destruction of the winding insulation overheating. The result is a decrease in the resistance of the winding, which in turn increases the current. The winding temperature increases and leads to the closure of a number of turns of the coil. It is therefore necessary to identify the presence of short-circuited turns as early as possible.
You will need
- - ohmmeter;
- - ammeter;
- - the voltmeter;
- - portable flaw detector.
Shorted turns in the coil winding define, measure coil resistance using an ohmmeter, or by removing the ammeter (voltmeter) when powered coil from the battery. Record the readings of the measuring device. Divide the voltage value of the current and calculate the resistance. If coil resistance was less (compared to nominal) and the short turns. Troubleshooting the rewind coil or its replacement.
To check the coil for a short use also another method. Connect it through an ammeter to the battery. Measure the amperage in the circuit of the winding. Now measure the amperage in the circuit of the winding other coil, known good. If the circuit is missing, both measurements will show approximately the same current.
For the detection of interturn short circuit in the windings of electric machines use a portable flaw detector. Connect the device to a power source and place it in the bore of the stator to the groove sections check the winding located between the air gaps of the steel packages flaw. About inter-turn short circuit will signal fire on the instrument lamp.
To manufacture the simplest flaw detector collect electrical steel core. Pull the core plates by bolts, isolated from steel strips. Wind on a core of 800 turns of wire of brand of PEV-section of 0.8 mm.
To check the windings put her on the "shoulders" of the device core. Put on plate, steel plate from tinplate. Connect the coil of the device to the network. Now slowly rotate the coil holding plate. If one of the pairs of windings the insulation is damaged, the steel plate is drawn.
By visual inspection the presence of interturn short-circuit without special equipment determined by the local destruction of the windings. Note also this sign as "coking" of oil and the interior surfaces of the device. Often with inter-turn short circuit will trigger automatic protection at start-up of the unit.
Advice 3: How to check the winding of the generator
To check the generating system and troubleshoot it enough to have an ohmmeter. However, more precise information about the wrapping nodes can be obtained by using special devices that search for faults in the windings by comparing their parameters with a known good coil. They are suitable for Troubleshooting as the stator windings and excitation.
You will need
- An ohmmeter, a device PDO-1
Check the winding of the rotor. To do this, turn on the ohmmeter to measure winding resistance and bring his findings to the rings of the rotor. Resistance serviceable rotor when voltage of 14 V is in the range of: generators that operate with voltage regulators designed for a maximum amperage of 3.5—4.0 And Is 3-5 Ohms, working with voltage regulators that are rated for the amperage And 5 - 2,5—3 Ohms.If the device showed infinite resistance, this means that the circuit of the field winding is broken. This usually occurs in the soldering of conclusions of a winding to the rings, when burned windings or when turning of the frame with the excitation winding on the pole half-sleeves-half. Also this is evidenced by the darkening and also shedding its isolation that can be detected visually. This fault leads to inter-turn short circuit in the winding, which is accompanied by a decrease in the overall resistance.To determine the partial winding short circuit when the resistance of the windings varies little, only a special device, such as PDO-1. When this occurs, the comparison of this coil with a known good. The excitation coil of the contactless generators (HA2, 955.3701) test using an ohmmeter, pin the ends of which are connected directly to the terminals of winding. Then check the no short to ground. To do this, one lead of the ohmmeter to bring his beak, and the other to any ring rotor, and the non — contact generators to the hub of the coil and any output coil. A good coil should show a gap on the ohmmeter, i.e. infinite ohms.
Check the stator winding. To do this, attach the ends of the ohmmeter to one terminal of the winding and package of iron, i.e., check for a short to ground. The device is a healthy coil should show an open circuit. Check winding short circuit in the stator windings. To do this, measure the resistance of the individual phases and compare the results with each other, the difference should not be more than 10%. The resistance phase is a fraction of an Ohm, so it requires high-precision measurement devices.Full information on the state of the windings of the generator can provide the device PDO-1, connected to the terminals of the three phases. When the phases are identical, the screen has one oscillographic curve, if not (due to inter-turn short circuit in phase) then the two curves. The measurement should be repeated, pre-change phase places. Thus you can find the different phases, for example, a different number of turns in them that can occur after rewinding the stator. Phase loss check with ohmmeter by connecting it alternately to the zero point and to the conclusion of each phase.
Advice 4: How to check the health of starter
For a comfortable and remote start car engine used starter. Therefore, its performance should always be at the optimum level. At the slightest remark on the device, it should be checked. The best way to stand.
Install the starter on the bench. Test its electrical and mechanical characteristics. Note, however, that the connecting leads from the power source to the ammeter and the contact bolt of the traction relay should be a cross section of 16 sq. mm. Starter connect a fully charged battery. The temperature during testing shall be (25±5) degrees. Brushes should be well lapped on to the manifold.
Check the operability of the device. Install source voltage 12V, the circuit between the "+" battery terminal 50 on the starter , check the switch. Closing it produces four enable starter with different conditions of braking: 2-2,4; 5,5-6,6; 9-10,8 and 11.5 to 12.5 Nm. The duration of each inclusion of a starter should not exceed 5 seconds, an interval between them of from 5 seconds. If the job starter is accompanied by abnormal noise or rotates the ring gear, it should be disassembled and check the details.
Test the starter in the full braking. This fully secure motionless ring gear of the stand, crank the engine and measure the current, torque and voltage, which should correspond to values not higher than 500 And not less than 14 Nm and do not exceed 6.5 V. the Duration of the process of inclusion should not exceed 5 seconds. In the case where the braking torque below the required figure, but the amperage is higher, then the cause could be shorting the windings to ground or a winding short circuit in the armature winding and the stator. If the brake time and current are below the standard values, it can be caused by pollution and oxidation of the collector, reducing the elasticity of springs of brushes or severe deterioration, excessive wear of the brushes stuck in the brush holders or loose conclusions of the stator winding, the burning or oxidation of the contact bolts of the traction relay of a starter.
Check the traction relay. To do this, set between the gear and the restrictive ring gasket with a thickness of 12.8 mm. plug relay. Power consumption-DC single relay should be no more than 23 A. Check the switching voltage at the two-winding relay. It should be no more than 9 V. If it is higher, then a faulty relay or an actuator.