Geeetech

So I was printing when I started to smell some thing burning and came across this lovely mess pictured below. Doing a quick search I found 2 others posting about the same issue in the same plug and pin. I'm curious if any one know what is causing this failure and how to prevent it from happening again.

http://www.geeetech.com/forum/viewtopic ... =10#p30911
http://www.geeetech.com/forum/viewtopic ... rnt#p28163

KrzyInuYasha wrote:So I was printing when I started to smell some thing burning and came across this lovely mess pictured below. Doing a quick search I found 2 others posting about the same issue in the same plug and pin. I'm curious if any one know what is causing this failure and how to prevent it from happening again.

http://www.geeetech.com/forum/viewtopic ... =10#p30911
http://www.geeetech.com/forum/viewtopic ... rnt#p28163

Hi,
I guess maybe there is a short circuit somewhere,which caused a high current.I saw you make some modifications on the board,i think you'd better have a check on your board before your printing.

The only mods I did was add a Bluetooth module for wireless serial communication (the 4 red wires) and a servo line for auto level (the red, Black, Yellow). Those have been there for a while and weren't the cause. I put a new plug set on and In testing every thing was fine till i started up the heaters, then things started to get hot and blew out the 5A fuse (had enough current going through it to cause it to glow red despite being ceramic) on the board. Did some checking and the Heat bed mosfet failed, doing research it seems the stock STP55NF06L mosfets being used one these and RAMPS 1.4 boards just are not enough for long run time prints with heat beds.

Needless to say I have some replacement fuses, IRLB8743PBF mosfets (over all the most recommended to use for replacement/upgrade of stock mosfets), and a RAMPS 1.4 kit on order to fix or replace this board depending on any other possible damage that happened I don't know about.

KrzyInuYasha wrote:The only mods I did was add a Bluetooth module for wireless serial communication (the 4 red wires) and a servo line for auto level (the red, Black, Yellow). Those have been there for a while and weren't the cause. I put a new plug set on and In testing every thing was fine till i started up the heaters, then things started to get hot and blew out the 5A fuse (had enough current going through it to cause it to glow red despite being ceramic) on the board. Did some checking and the Heat bed mosfet failed, doing research it seems the stock STP55NF06L mosfets being used one these and RAMPS 1.4 boards just are not enough for long run time prints with heat beds.

Needless to say I have some replacement fuses, IRLB8743PBF mosfets (over all the most recommended to use for replacement/upgrade of stock mosfets), and a RAMPS 1.4 kit on order to fix or replace this board depending on any other possible damage that happened I don't know about.

A short circuit is one reason,another reason may be the total power exceeds the rated power of the burnt fuse because of overloading,you can change another fuse which has a higher rated power,you can test if it is the reason by unplugging the mods you've made.

It's not the mods, they have been on there for over a year and have caused no issue or could even draw that much current. No looking at the board again and having a day to think about it and knowing about the bad mosfet. the mosfet for the heatbed failed and caused the heatbed to be on all the time and cause excess current draw, add in the hot ends trying to heat up at the same time and you exceed the current capacity of the connector causing it to melt and fail. The failure of the 5A fuse was also from the mosfet being bad, causing excess current draw on the 5A 12v line that is used to to switch the mosfets and power board logic. No this is all down to the use of a part that isn't capable of handling heavy current loads over a long period of time.

Over all this isn't a bad board and i like it a lot, it just could use some beefing up in some areas, like better mosfets and a heavier power connector or using a 6 pin connector that can have 2 pins/wires for the 5A line and 4 pins/wires for the 15A heater line, and maybe adding a few solder pads for some of the unused pins so we can have easy access to the unused serial lines and control pins for adding Bluetooth modules and auto leveling servos.

Yes,in summary,it was caused by the heavy load which the excess current brought to it.

And thanks for your attention and advice,we'll consider it.

Regards

Hello,
Where can I get the fuses for this board?

foxy101 wrote:
Hello,
Where can I get the fuses for this board?

You can contact the sales(sales@geeetech.com) to get it.

you can also get them from on-line distributors like digikey or search ebay, I got mine from a local guy in the US off of ebay. just look for LF05, LF07, LF15, or any that are Littelfuse 1808 SMD in the amp rating you want, Typically controller side is a 5-7 amp and the mosfet/heater side is 15 amp.

No mods to mine and my power plug is burnt up worse than that. I can't unplug it from the board.

Excessive use?? I started 4 hour print this morning and smelled the odor but thought it was the new bed glue that I was using. It turned out to be the plastic power plug melting while I was printing. When I tried to start the next print the power blinked out when the Bed Heating was done and right when the nozzle started to heat.

good luck to you
Dave