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What do you think will happen and why?Junior01 said:I have a situation like on picture in attachment. I want to know, why I have a diode between two sources? What will happen without diode?
Thank you.
Probably something with sources, but I don't know what.phinds said:What do you think will happen and why?
Your questions aren't a point of this thread.phinds said:How far along are you in your studies of electrical circuits?
His questions are very appropriate. He is trying to get you to talk through the problem. That is a good way of helping people to learn a subject. If he just told you the answer, then the next time you have a similar question, you will have to go find somebody to tell you the answer. But if you get in the habit of doing some reading on your own and trying to talk through a problem, you will find that you are learning more and better.Junior01 said:Your questions aren't a point of this thread.
berkeman said:His questions are very appropriate. He is trying to get you to talk through the problem. That is a good way of helping people to learn a subject. If he just told you the answer, then the next time you have a similar question, you will have to go find somebody to tell you the answer. But if you get in the habit of doing some reading on your own and trying to talk through a problem, you will find that you are learning more and better.
So please tell us what you think the function of the diode is in this circuit. What does a diode do? Can you sketch the I-versus-V curve for a diode? What happens if you connect two voltage sources in parallel directly?
berkeman said:His questions are very appropriate. He is trying to get you to talk through the problem. That is a good way of helping people to learn a subject. If he just told you the answer, then the next time you have a similar question, you will have to go find somebody to tell you the answer. But if you get in the habit of doing some reading on your own and trying to talk through a problem, you will find that you are learning more and better.
So please tell us what you think the function of the diode is in this circuit.
In general, DC power supplies are not designed to work in parallel. It is hard for them to have exactly the same output voltage, which means that one or the other will supply most of the load current. One solution is to "diode OR" their outputs...Junior01 said:I know that for example two generators can work in parallel if they are synchronised. But here I have two 24V DC system, and I don't know why they can not work in parallel.
berkeman said:which means that one or the other will supply most of the load current
Let's say you want to supply 10A at 12V, so you try to do it with two 5A, 12V DC power supplies. First of all, if they are switching power supplies, they can cause each other to go into oscillations (which is bad). if they are linear power supplies, the one with the 12.1V output will will go into current limit trying to supply the full 10A, which will cause its output to drop (crowbar) and the other supply will then try to supply 10A, so it will crowbar too.Junior01 said:Why it is bad? Why it's important from which source consumers get more "energy"?
berkeman said:Let's say you want to supply 10A at 12V, so you try to do it with two 5A, 12V DC power supplies. First of all, if they are switching power supplies, they can cause each other to go into oscillations (which is bad). if they are linear power supplies, the one with the 12.1V output will will go into current limit trying to supply the full 10A, which will cause its output to drop (crowbar) and the other supply will then try to supply 10A, so it will crowbar too.
You may get lucky if the two power supplies have almost exactly the same output voltage (unlikely), and if they have a moderate output impedance. But in the general case, DC power supplies can't just be paralleled without something like the diode OR connection.
When you see parallel battery connections, it is between batteries from the same manufacturer, same age, same charging history, etc. This causes them to have about the same output voltage versus time, and their inherent source resistance helps to balance them.
berkeman said:https://www.eetimes.com/document.asp?doc_id=1273175
CWatters said:Why are the two sides linked at all?
Who determined which way the diode should point?
I think that diode is there to block current from second charger to go "on the left side".Tom.G said:First, do you know what a diode does?
Tom
I agree, so far. Now how about when the power fails and both chargers are off?Junior01 said:I think that diode is there to block current from second charger to go "on the left side".
Tom.G said:I agree, so far. Now how about when the power fails and both chargers are off?
Tom.G said:What about the the safety system on the right side? Does it shut down? Why?
Junior01 said:In such situation it's possible that computers on the left side need more energy, so the left battery will be drained, while those computers can't draw current from right battery due diode. The right battery stay "safe" to supply consumers on the right side.
Absolutely correct. I think you just answered the question you first asked!Junior01 said:In such situation it's possible that computers on the left side need more energy, so the left battery will be drained, while those computers can't draw current from right battery due diode. The right battery stay "safe" to supply consumers on the right side.
A diode is a two-terminal electronic component that allows current to flow in only one direction. It acts as a switch, allowing current to pass through when the voltage is above a certain threshold, known as the forward bias voltage. When the voltage is below this threshold, the diode blocks current from flowing.
The diode between two sources is used to protect one source from voltage spikes from the other source. It acts as a barrier, allowing current to flow from one source to the other while blocking any reverse current that may damage the sources.
When the voltage of one source is higher than the other, the diode between the two sources allows current to flow in the forward direction, from the higher voltage source to the lower voltage source. However, when the voltage of the two sources is equal or the lower voltage source is higher, the diode blocks current from flowing in the reverse direction, protecting the sources from any potential damage.
There are several types of diodes that can be used between two sources, including the standard silicon diode, Schottky diode, Zener diode, and avalanche diode. Each type has its own unique characteristics and is suitable for different applications.
Yes, a diode between two sources can also be used for other purposes, such as rectification, signal modulation, and voltage regulation. It can also be used in various electronic circuits and systems to control the flow of current and protect components from damage due to voltage spikes.