I have this vx2200d that belongs to a buddy, he brought it to me saying he was told it works, but as soon as i hooked it up, smoke came out of it, and a piece of plastic from a power section mosfet blew out of the side(side panel was pulled off).
so i looked at it from the outside first, and noticed one of the end caps looked bent as if it had been dropped hard on the rcas, once i took the amp apart, i found about 3 blown caps and a blown mosfet. and also notices someone had tried to solder the rcas back in.
i plan on replacing the whole bank of caps in that area, and replacing ALL fets in the power section, just wanted to run this across the forum before ordering parts. i have a feeling something else caused this, and the blown fets and caps were a byproduct of that. if there are any ideas of what i should check out first before ordering parts, i would appreciate it. thanks
so i looked at it from the outside first, and noticed one of the end caps looked bent as if it had been dropped hard on the rcas, once i took the amp apart, i found about 3 blown caps and a blown mosfet. and also notices someone had tried to solder the rcas back in.
i plan on replacing the whole bank of caps in that area, and replacing ALL fets in the power section, just wanted to run this across the forum before ordering parts. i have a feeling something else caused this, and the blown fets and caps were a byproduct of that. if there are any ideas of what i should check out first before ordering parts, i would appreciate it. thanks
Did the smoke come from the FETs or from the cap?
The caps can fail for a number of reasons:
shorted inductor
abuse
arcing to the board
You need to replace all of the power supply FETs if one failed.
The caps can fail for a number of reasons:
shorted inductor
abuse
arcing to the board
You need to replace all of the power supply FETs if one failed.
im pretty sure it came from the fet, but didn't actually see it. the caps are just swollen, and didn't erupt or anything. i will replace all the power supply fets, and the small bank of large caps.
do you think there are anymore issues i should look into before ordering parts?
do you think there are anymore issues i should look into before ordering parts?
Well seems the only caps I can find are snap in style. I really stay away from these generally,will they be OK?
Also, I was looking online at another repair done to a vx2200, and noticed they were using irf46n fets. Mine has irf44n fets, which of the 2 are supposed to be used?
Both the Z44s and Z46s were installed by the manufacturer.
I don't suggest that you replace any parts except the ones that are blown (and those in parallel with them) and possibly Q124 and Q125.
I don't suggest that you replace any parts except the ones that are blown (and those in parallel with them) and possibly Q124 and Q125.
have you ever shopped @ allied electronics? just wanted to see what the deal with them is as the irfz44n fets are less then half the price of mouser, and the caps are cheaper their also.
I don't generally buy from Allied. Maybe someone else can tell you whether they're OK to deal with,
They are a good vendor, I have not had any issues with any order I have placed with them. It is possible that their stock is older and priced based on their original cost or it could be that they just purchased more of that item than some of the other vendors and can pass a better price on to you. I have purchased items that were at a good price, then it went out of stock and when it was replentished it suffered a price increase that was more in line with the others.
I don't use them too often as the "extra" costs can add up and errode all the savings, like Tax, Handling, and an under minimum order value charges, some of which may not apply to anyone else.
I don't use them too often as the "extra" costs can add up and errode all the savings, like Tax, Handling, and an under minimum order value charges, some of which may not apply to anyone else.
alright, i have got all my parts in, i replaced all the caps, now im replacing the power supply fets.
I seem to be having issues with solder pads coming off, i have had several just come off and stick to my iron.
My question is, is there any way to fix this? maybe bridge solder to the trace in the board or something? or is there something better? please let me know, i just spent the money on these parts now this is happening
I seem to be having issues with solder pads coming off, i have had several just come off and stick to my iron.
My question is, is there any way to fix this? maybe bridge solder to the trace in the board or something? or is there something better? please let me know, i just spent the money on these parts now this is happening
They can come off for a number of reasons.
You'd need to post a photo of the damage before anyone can offer suggestions on repairing it.
You'd need to post a photo of the damage before anyone can offer suggestions on repairing it.
Unless you are absolutely, certainly, positive that you connected it properly, I looks like a perfect example of reverse battery connection. I've seen it a hundred times.
it may have been a reverse of power connections, but i dont have the end plate, so i had to look up a picture of the amp to find out which goes where. is there anyway to tell by looking @ the board which is + and which is -
Use a meter. Hopefully, after a fuse, the battery positive will go to the power supply toroid transformer, primary centertap, then if the FB31N20D transistors are all near the transformer then the Drains or center leads and metal tabs are powered from the other two outer taps on the transformer primary in push pull configuration.
The other transistors, IRFZ44 and IRFZ46, are probably arranged on each side of the heatsink in pairs and are the N and P channel amplifier transistors and are probably intact because they are powered from the transformer secondary.
Here is a PERFECT example with a great explaination:
Basic Switching Power Supply Design Tutorial
The other transistors, IRFZ44 and IRFZ46, are probably arranged on each side of the heatsink in pairs and are the N and P channel amplifier transistors and are probably intact because they are powered from the transformer secondary.
Here is a PERFECT example with a great explaination:
Basic Switching Power Supply Design Tutorial
Use your meter to verify that the legs with the damaged via's (pads) are making a connection to the components that they should be connected to.
If your iron's heat is not adjustable, you have to get a little quicker with with your soldering / de-soldering to keep from baking them off the board. Easier said than done.
If your iron's heat is not adjustable, you have to get a little quicker with with your soldering / de-soldering to keep from baking them off the board. Easier said than done.
Don't worry about the pads. If they're gone... they're gone. It's the gate connection and will go to the adjacent 10 ohm resistor. You can compare it to the connections on the other FETS on the other side of the board. They're all wired the same in two banks.
Use a short piece of solid gauge wire from a resistor lead.
If your quick about it, to remove the FETS, add solder to all three leads heat them all up and carefully slide the FET out, being careful of the plated holes for the leads.
Use a short piece of solid gauge wire from a resistor lead.
If your quick about it, to remove the FETS, add solder to all three leads heat them all up and carefully slide the FET out, being careful of the plated holes for the leads.
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