Configuring DC mix connection circuit

Thread Starter

Mohammad abdullah

Joined Mar 30, 2015
25
Hi,
I want to connect Peltier 12706 to solar panel that produce 11A ,3 Peltier in Series and then 3 rows parallel of the series total 9 Peltier in each string I want 2.5A to be passed only so the hot side doesn't get too much hot I should use DC-DC booster to get 18V for every string of 3 but for current, What should I do so it will not pass more than 2.5A?
P.png
 

AlbertHall

Joined Jun 4, 2014
12,346
Each element is ≈2Ω making a string of three ≈6Ω. Applying 18V would give each string about 3A.
The total power for three strings would be 160W. If the solar panel will produce 11A at 14.5V it will be fully loaded, but there will be losses along the way so it might struggle a bit to manage that.
 

Thread Starter

Mohammad abdullah

Joined Mar 30, 2015
25
But I don't have to have any thing between the booster and the Peltier so one string don't take all the power letting the others power less.

My solar panel rated 180W and I can arrange 200W but I know that it will not produce all that especially our ambient +40 C sometimes 52C because of that I don't want it to got fully loaded so it well not melt down.
 

AlbertHall

Joined Jun 4, 2014
12,346
But I don't have to have any thing between the booster and the Peltier so one string don't take all the power letting the others power less.

My solar panel rated 180W and I can arrange 200W but I know that it will not produce all that especially our ambient +40 C sometimes 52C because of that I don't want it to got fully loaded so it well not melt down.
The three strings will share the available power equally.
The solar panel will not be harmed at all by overload - they can be quite safely short-circuited. As you draw more current the voltage will fall so there is an optimum load to get maximum power from a solar panel.
 

Thread Starter

Mohammad abdullah

Joined Mar 30, 2015
25
The three strings will share the available power equally.
The solar panel will not be harmed at all by overload - they can be quite safely short-circuited. As you draw more current the voltage will fall so there is an optimum load to get maximum power from a solar panel.
So the governor of the current will be the panel produce current, but if I want to control the current flow I should put diode.
 

AlbertHall

Joined Jun 4, 2014
12,346
A diode won't control the current. If your DC-DC converter has an adjustable output voltage you can use that to control the current.
 

Thread Starter

Mohammad abdullah

Joined Mar 30, 2015
25
A diode won't control the current. If your DC-DC converter has an adjustable output voltage you can use that to control the current.
How is that will be? I know that if you increased the voltage the current flow increases but for the Peltier isn't it has maximum voltage rate.

I tried one and it explode :)
 

AlbertHall

Joined Jun 4, 2014
12,346
Yes, they have a maximum voltage but the arrangement you have described is well below the maximum for the peltier you have chosen - check the datasheet..
 

R!f@@

Joined Apr 2, 2009
9,918
I tried one and it explode :)

No matter how you control the voltage.

Your peltier will explode if you do not mount it on a HEATSINK

You can adjust the Peltier voltage to minimize current but you will lose efficiency.
You can ON OFF the peltier power to control the cold temperature
 

R!f@@

Joined Apr 2, 2009
9,918
Why don't you understand that the hot side will get hot. Even with low current, it will heat to the point where it will split into 2 or explode.
YOU NEED A HEATSINK
 

Thread Starter

Mohammad abdullah

Joined Mar 30, 2015
25
Why don't you understand that the hot side will get hot. Even with low current, it will heat to the point where it will split into 2 or explode.
YOU NEED A HEATSINK
it will be controlled by thermostat at hot side 50 degree bellow joints melting point
also I want to use it as water warmer :)
 
Top