EINHELL BT BC 15 - Voltage Output Issues When Switching Between Settings

Question

Hello.
Rectifier as in the subject. After switching to 24V, a voltage of about 14V appears on the terminals, after switching to 12V - 7V, after switching to 6V - less than 4V. I am asking for advice, what could have been damaged?

Best regards!

Adamcyn · Accepted Answer

Of course. It is also worth replacing the sternum prophylactically.

Adamcyn · Answer

Perhaps it is operational. What charging current does the built-in ammeter show? Rectifier voltage measurement not connected to the battery it is not authoritative. Connect to battery and then measure charging voltage and current.

autocezar · Answer

12.4 V battery after connecting the voltage at the terminals 12.4V After unplugging about 7V

Adamcyn · Answer

What current is the ammeter showing?
If it does not show anything - it is actually a damaged rectifier.

If something shows, measure the voltage after 30 and 60 minutes with the battery connected - it should increase.

autocezar · Answer

YES THE LAYOUT IS SIMILAR BUT WE HAVE MORE HIGH GREEN RESISTOR

Adamcyn · Answer

You can check it? You will provide photos, especially the one with the thyristor designation.

autocezar · Answer

the built-in ammeter shows nothing. The tip does not work The voltage measurement after 30 and 60 minutes gives the same values. 12.4V Added after 3 [minutes]:

Adamcyn · Answer

Measure this green resistor (? and an alternating voltage connected to the bridge rectifier.

autocezar · Answer

A resistor at low idle 690k when connected to the network indefinitely 5.9V alternating voltage across the bridge

Adamcyn · Answer

So it is damaged, because it should have a few ?. Can you read what is written on it?

autocezar · Answer

Unfortunately, there are no subtitles, it is possible that they were once, but now there is nothing. It's also a bit cracked. Start by replacing this resistor?

autocezar · Answer

Thank you for the hint, I will start by replacing the resistor.

mamkonto · Answer

Has the rectifier been started? A colleague brought the same rectifier, similar symptoms, after disconnecting the battery at the 8 V output, a damaged transistor.

Krzysztof Kamienski · Answer

About Jesus Christ Superstar ...... And what is its value, as long as it is allowed to ask? Which one ?? How measured ?? To sum up, you made me laugh since the morning, Dear Group of Experts

Adamcyn · Answer

The one we are discussing (photo # 7) does not have a transistor. If your transistor is damaged, replace it.

autocezar · Answer

Has the rectifier been started? unfortunately it failed. I do not know what resistor needs to be replaced, what are its values. No markings on the resistor

Anonymous · Answer

The original green large 40 W resistor has the symbol RX 20-40 0.12 ohm 5%. It's hard to measure these 0.12 ohms with a poor multimeter.
A battery with an internal short circuit has finished this resistor. The multimeter showed OL. Out of curiosity where the wire is burnt, I scraped the paint off the resistor "like a carrot" It turned out that the wire was damaged at the connector itself.
I couldn't find the original resistor, so I put in 2 connected in parallel 0.22 ohm 50W.
As for the voltages measured on the crocodile clips, in fact, when the rectifier is working in neutral, they are "strange", especially when we turn the knob around its axis several times. However, after connecting the battery, everything stabilizes.
Maybe someone will explain what is the reason for this large resistor in this rectifier?
The large blue knob, the factory has no clear marking and you can set 24 V instead of 6 V, so it's better to make a clear sign yourself where up and down.