Normal battery charging in any generator is due to the functioning of the diode bridge. In the event of a breakdown, the item is sent to a service center for repair. But in most cases, the knowledge of how to ring the diode bridge of the generator is enough to troubleshoot the problems that have arisen. The master needs to be able to understand the features of the element and determine the cause of the malfunction.
Content
- How the bridge works
- Causes of breakdowns
- Diode test
How the bridge works
The diode bridge in the generator design acts as an electricity rectifier. The current is converted using four or six diodes combined in one circuit. It is she who is called the bridge.
It has a simple function - it conducts the electricity generated by the generator to the battery and prevents it from going in the opposite direction. First, a certain resistance is generated, then it tends to infinity.
A defective element causes the electronic parts in the car to stop working.
The battery will malfunction, and since it powers the starter, the car simply won't start. Before repairing, you need to identify the main cause of the breakdown, and then find methods to eliminate it.
Causes of breakdowns
If the battery stops working, then you need to check the diode bridge of the generator with a multimeter. Breakdowns can occur for several reasons:
- moisture inside the battery;
- polarity reversal of the terminals;
- breakdown of electronic circuits, which is difficult to fix on your own.
The most common problem is the ingress and accumulation of moisture, which seeps under the body when washing the car. You should also avoid driving through deep puddles. Terminals can be reversed if the charger is connected incorrectly or lighting. Therefore, you need to ring the generator winding, remove the damaged elements and install new ones in their place.
The battery has a direct connection to the diode bridge and must be carefully ringed. Breakdowns can lead to some consequences: electricity may not be supplied to the generator at all, or the latter receives current at excessively high frequencies, which causes the electrolyte to boil.
The problem must be solved as quickly as possible. If the breakdown is not eliminated, the battery will deteriorate irrevocably, and as a result, you will have to buy new equipment. You can check the generator winding in two ways - using a light bulb or a multimeter.
Diode test
When checking with a lamp, you need to remove the bridge from the generator. With the assembled element, you need to touch one of the battery terminals. Contact must be observed, it must be strong and durable. The plus pole of the light bulb touches the same part of the battery. Then they ring each contact in turn and proceed to checking the starter winding.
A broken bridge is indicated by a lit light bulb. The circuit must be connected in stages through one diode. So you can identify the faulty part and replace it with a new one. If you need to check the bridge for breaks, then its negative pole is thrown over the positive terminal of the battery. The lamp is connected to the battery, and the free contact is connected to the diode so that the signs coincide. If the bridge is working properly, the lamp should light up. If there are breaks in the circuit, then it will not glow at all or will flash several times.
To check the generator integral, the bridge is also removed and each diode is ringed separately. The device is set to the "ringing" mode. If he does not have such a function, then it is enough to choose a resistance indicator of 1 kOhm.
This will allow the device to react if two contacts are closed. The bridge is divided into two parts - power and auxiliary diodes. The scheme for checking them is the same. When the working diode rings, the resistance in the direction of the battery will jump to several hundred ohms, and on the way back it will tend to an infinite number.
The multimeter probes are connected to the diode contacts and measure the indicators. Then the ends of the device are reversed and the resistance value is checked. The diode turns out to be burnt out if the multimeter showed different values. The procedure is repeated for each diode. A zero value appears if there are open circuits in the circuit. Using a multimeter, you can quickly identify a broken diode.
The lamp is used in the absence of a measuring device, but this verification method has several disadvantages:
-
at a low current, the lamp may blink not due to a breakdown; - you can work only with the bridge removed from the generator;
- the light bulb may not always be at hand;
- if handled carelessly, the check leads to a short circuit.
The defective diode is replaced with a new one using a soldering iron. A new element can be purchased at any hardware store, and it is not difficult to attach it yourself.
There are many generator models, for some of them it is difficult to find a part, so it is better to repair it.
