Trying to replace LED chip on floodlight. What is the white stuff?


  #1  
Old 10-02-15, 04:52 AM
A
Member
Thread Starter
Join Date: Oct 2015
Posts: 1
Upvotes: 0
Received 0 Upvotes on 0 Posts
Trying to replace LED chip on floodlight. What is the white stuff?

Hi, first post

I opened up a 50W floodlight to replace the LED chip because it stopped working and there is this white stuff between the chip and the metal. The screws are also covered by this stuff.

What is it called?

I am thinking it is either a thermal insulator to separate the electrical components from the metal casing or it is a thermal heat-sink paste. If it is an insulator, then I will have to get some to put behind the new chip so that the casing doesn't conduct electricity.

It smells like paint/petroleum and somewhat sticky.

Here are pictures:

View image: IMG 0314

View image: IMG 0315
 
  #2  
Old 10-02-15, 06:27 AM
C
Member
Join Date: May 2015
Location: USA
Posts: 3,191
Received 176 Upvotes on 144 Posts
Looks like thermal paste. There may be an insulator as well, but it would be a thin sheet material, not just a paste. It's to help conduct heat away from the LED chip. zillions of sources online, and larger computer stores would also have it as it used between CPU chips and heatsink.
 
  #3  
Old 10-02-15, 08:11 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,675
Received 4,099 Upvotes on 3,682 Posts
Yes...... it is thermal transfer grease. It's used to fill in the microscopic gaps between the LED engine and the heatsink.
 
  #4  
Old 10-13-15, 04:28 PM
M
Member
Join Date: Oct 2015
Location: USA
Posts: 95
Upvotes: 0
Received 0 Upvotes on 0 Posts
It's heat sink compound. I have used quarts of it in my lifetime.

If insulation is also needed, a thin plastic or mica sheet is included.

Aren't you supposed to just replace the entire light?

And how do you know it is the LED chip that failed? In my experience, the power supply fails, not the LED.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: