CG Leganza 88DDT8 PLC Teardown

CROMPTON GREAVES (CG) LEGANZA 88DDT8

This PLC, which also may belong to the programmable relay category is designed, built and marketed by Crompton Greaves, an Indian company who made and markets a broad range of equipment for the electric business. Information about this PLC is very scarce, as the manufacturer's home page doesn't give a clue of its existence. Visually is very similar to other programmable relays like Siemens Logo! or Allen-Bradley Micro 810. There isn't a production date code on the label nor in PCBs and it is likely a lot of the assembly process is done by hand.

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Here is the list for the required components for this project with the absolute lowest prices! If you find something cheaper somewhere, please msg me!

• Plastic spudger or pry tool ► ( http://goo.gl/xfxK9M )
• 3 mm phillips screwdriver ► ( http://goo.gl/pwGy8D )

TEARDOWN PROCESS

Insert the spudger and make a lever to unlatch the plastic hinge that keeps together the upper and lower part of the case, pull slightly to separate both parts. Once unlatched repeat the process with the other latch on the opposite side and remove bottom cover.

PCB REMOVAL

With one hand hold firmly the PLC and with the other hand using the screwdriver, press the outermost screws of the terminals. Push a little bit in sequence, all the four screws near the corners, until the PCB emerges a bit out of the case.

Once a significant portion of the PCB assembly is out of the case, the screwdriver isn't required anymore, hold the case with one hand pulling the PCB assembly with the other to remove completely.

As you can see all the pieces were pressure assembled, no screws were used to hold any part!

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MORE INFO

For more info, please visit: Absolutelyautomation.com