Making ATX terminal block interface - advice regarding cooling (crimp only)

Kabelsalat

Jul 5, 2011
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Jul 5, 2011
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I recently made a simple ATX bus bar interface using two 9 pin terminal block <ebay-link>. This works well. I used soldering, a non-conductive stiff plate as a holder and 1mm² (some of the terminals I used two in parallel for better load balancing) Al wire. This works great.

However I'm starting to making plans to create another one, this time attempting to make it as perfect as possible in terms of amount of energy that can flow through each pin on the terminal block and the ability to transfer heat from the pins to the back plate (stiff Alu plate).

For the second type, I'll use crimp only - i.e. no soldering. Assuming the connectors of the terminal blocks and the 24 pin, 8-pin and 4-pin ATX connectors would be the weakest points in terms of heat dissipation, I'm playing with the idea of using a Al plate to mount the ATX connectors and terminal blocks onto.

So after the connectors are mounted on the plate, the pins are located in the center of each hole with some distance to the edge - I need some material to fill in in order to prevent short in case some outer force make one two or more pins to bend and make contact to the Al mounting plate.
Also, I need the material to have the following properties:
Non-flamable
Non-conductive
Somewhat hard to not give way in case e.g. the device fall and hit the edge of a table (I'll probably use some plastic glue anyway to further protect against damage from outside, so this is not the most important property)
Good thermal conductor - Will transfer heat form the legs and crimps on the terminal blocks to the mounting Al plate.
 

Delta Prime

Jul 29, 2020
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I need some material to fill in in order to prevent short in case some outer force make one two or more pins to bend and make contact to the Al mounting plate.
Also, I need the material to have the following properties:
Non-flamable
Non-conductive
Ceramic insulators (PCB standoffs) if you wanna go frugal. Press fit into your back plate. Let the natural air convection currents do its thing.
get away from thermal compounds to fill a void ,be-it, paste grease,or glue.
They are applications specific to metal plates compressed against one another, thermal compound is used in limited amounts just to fill in the microscopic air pockets that are trapped in the interior of two plates.
The best thermal compound is an order of magnitude worse then the thermal conductivity of aluminum, but 100 times better than air.
(This inaccurate statement was used to paint a picture).
The link you have supplied, there’s no data sheet to be found, and you have not disclosed the power requirements needed?
Single-level terminal blocks can handle currents up to 175A,can accept a wide range of wiring sizes from 26 AWG to 2/0 AWG and have a 100kA SCCR rating.
Reference: UL(E179129) for
CU ,copper wire only and only one conductor per terminal.
CE(EN 60947-7-1)
(off-topic)
You have been here since 2011 you are a fanatic. I salute you and you’re my new hero!
 
Last edited:

Bluejets

Oct 5, 2014
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You are overthinking the whole connections/terminals issue.

Any appropriate connection should produce little or no effect what-so-ever considering the current available.
 

Harald Kapp

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Nov 17, 2011
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Use Copper wire instead of Al wire. Copper has less specific resistance, lowering the loss and thus the thermal stress.

If you need, for whatever reason, to keep your setup, consider kevlar tape as an insulator. It is both a good insulator and is mechanically strong to resist stress.
 
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