Well i've been stumped for a couple weeks now. I have 4 Hifonics Bxi 2010d's in need of repair. Ive have pretty common knowledge of the amps and basically have been lurking here in the forums and over at bcae1.com for a while now. 2 of the amps are pulling excess current when I have it hooked up to a regulated power supply. once I hit about 8.5 to 9 volts the amp powers up green and then hits protect mode at about 9.5 applied voltage. Pulled the driver board and still the same outcome. One of the amps has a high pitch squeel comming from it. My guess would be the power transformer which could be bad. On another one the IRF 640's are all replaced brand new but the last 3 closest to the RCA jacks are not reading the rail voltage on the center terminal (my guess was power transformer or drivers.) I am able to get green at 12V but no sound to anything. Looking for some input since I have 4 boards to play with. 2 are version 1.1 with the onlything I noticed different were the rectifiers Fmu 32U/ Fmu 32R on Version 1.0 and fmg 33s/ fmg 33r on version 1.1. Just looking for some insight common problems with this particular model and any suggestions is much appreciated!
Is the amp pulling excessive current or simply going into protect?
The positive rail voltage will be on the center leg of half of the outputs. The negative rail will be on the 3rd leg of half of the outputs. This applies to most amps that use the same part number outputs for both the high and low side FETs.
If you have multiple amps, only refer to one amp per thread. Start new threads if you have other amps.
The positive rail voltage will be on the center leg of half of the outputs. The negative rail will be on the 3rd leg of half of the outputs. This applies to most amps that use the same part number outputs for both the high and low side FETs.
If you have multiple amps, only refer to one amp per thread. Start new threads if you have other amps.
Well from what I can tell around 9.5 V the amp will switch into protect mode and is drawing about an amp. Ive been using a working one as a reference and even at 12V with and with the level set low it doesnt go over an amp so thats why I assumed it was excess current draw.
Depending on how bad the amp failed, the copper trace that ties the fet leg to the rail will sever and you need to bridge it.
If you removed the driver board and the amp is still going to protect, check the output fets. The AQ2200 schematic is close to that design and may help you. send me an email if you would like a copy. brandes.cm@gmail.com
If you removed the driver board and the amp is still going to protect, check the output fets. The AQ2200 schematic is close to that design and may help you. send me an email if you would like a copy. brandes.cm@gmail.com
Under normal operating conditions, these amps can draw over 20 amps for about a second when powering up.
What are you using to power the amp?
What are you using to power the amp?
That was my suspision Brandes.cm as the board doesnt look into well of shape. There are several solder pads seemingly burn/missing and I am assuming the vias could shorted but havnt checked yet. But it was working fine until it jumped to protect, then I replaced exact components from Digikey except for the T0-220FP package
PF75nf75:
STP75NF75FP STMicroelectronics | 497-12618-5-ND | DigiKey
IRF 640N:
IRF640NPBF International Rectifier | IRF640NPBF-ND | DigiKey
Gate and driver resistors have check out fine as well as the drivers.
As for the Power supply I am using:
3in1 SMD Hot Air Iron Gun DC Power Supply Rework Soldering Station Welder 11 Tip | eBay
It has a protect mode which cuts it off at 1 amp current draw and adjustable voltage but I have even an Atx power supply:
Newegg.com - XFX Black Edition P1-750B-CAG9 750W ATX12V v2.2 / ESP12V v2.91 SLI Ready CrossFire Ready 80 PLUS SILVER Certified Modular Active PFC Power Supply
Which I am using to test without the Amp protected. Still goes into protect mode :/
PF75nf75:
STP75NF75FP STMicroelectronics | 497-12618-5-ND | DigiKey
IRF 640N:
IRF640NPBF International Rectifier | IRF640NPBF-ND | DigiKey
Gate and driver resistors have check out fine as well as the drivers.
As for the Power supply I am using:
3in1 SMD Hot Air Iron Gun DC Power Supply Rework Soldering Station Welder 11 Tip | eBay
It has a protect mode which cuts it off at 1 amp current draw and adjustable voltage but I have even an Atx power supply:
Newegg.com - XFX Black Edition P1-750B-CAG9 750W ATX12V v2.2 / ESP12V v2.91 SLI Ready CrossFire Ready 80 PLUS SILVER Certified Modular Active PFC Power Supply
Which I am using to test without the Amp protected. Still goes into protect mode :/
a 1 amp power supply is insufficient for this amp.
Computer power supplies are notorious for shutting down when trying to power an amp with them. I get a lot of email from people that are using ATX supplies and the only real problem is that the supply shuts down. The problem is the surge current. Amps without soft-start are more likely to cause the supply to shut down than those with soft-start. Have you ever used the computer power supply to power this amp (or one of the same model) up before?
Computer power supplies are notorious for shutting down when trying to power an amp with them. I get a lot of email from people that are using ATX supplies and the only real problem is that the supply shuts down. The problem is the surge current. Amps without soft-start are more likely to cause the supply to shut down than those with soft-start. Have you ever used the computer power supply to power this amp (or one of the same model) up before?
Yes, the amp was running fine for 3 months. What would be your suggestion for power within the home? I fell in love with fixing these amps and electronics about this time last year so im all ears man. Ive had an atx problem with a previous power supply that started smoking with an amp hooked up and ended up sending the amp into protect mode. Differnet model, differnt story. But as for the bxi 2010d has been running fine until I blew the power transistors and output transistors. Replaced them Wired it back up and was getting no sound. After trying various speakers known to work it ended up going into protect mode. Pulled the output board still protect as well as checking all the resistors and mosfets for correct voltage along the way. Even tried swapping the logic board. That's pretty much the history of this amp.
If you're going to repair amps, you should get a power supply with current and volt meters. Variable voltage is important. Variable current limiting is a nice feature but not absolutely necessary. The Pyramid PS-52KX is a decent budget supply. The Astron VS-70M is a better option if you can justify spending a bit more.
I don't quite understand what you wrote. You state that the amp was running fine. Was it running fine from the ATX supply? Did it ever work properly from the ATX supply you currently have?
I don't quite understand what you wrote. You state that the amp was running fine. Was it running fine from the ATX supply? Did it ever work properly from the ATX supply you currently have?
That is correct, the amp was working good with no problems from the atx power supply for 3 months.
Regarding the amp, I have it working had some pulled vias that I just fixed with some wire but i'm not getting any output to the speakers. What would be some points to check on the board to to locate the problem? Both negative and positive rail voltage is at 61V and -61V for the output fets.
Checked em again, all appear good. I was checking schematics and I think the problem is somewhere from the ic101 to 1c 110 area not getting input voltage. I may be wrong as im am still in the learning stages. What would be the source of input voltage to these?
When you state that it's working, what do you mean?
Is the relay engaging?
How are you checking for signal on the op-amps?
What type of signal are you driving into the amp?
Is the relay engaging?
How are you checking for signal on the op-amps?
What type of signal are you driving into the amp?
How would I check if the relay is engaging. I usually here it switch once and then not herd from again. I dont have an oscilloscope so the best thing I can do is change em out for otheres until I can get my hands on one. I have been using either an ipod or a computer for a source of input into the amp.
And by working I mean Powers up no protect even with the driver board in and was wondering as if you would have a reference to what the voltage readings should be on pins 1-11 of the Driver board IC201 And the Ic101 con-pwm1 board.
If the relay clicks once (not twice very quickly), it's likely engaged.
Measure the DC voltage on the output transistors with the black probe on leg 3 and the red probe on leg 1. Do you read ~5v on each of them? Do NOT allow the probe to short to the clamps or anything else.
I don't have the voltages for those.
Are you sure that the driver board is OK?
Measure the DC voltage on the output transistors with the black probe on leg 3 and the red probe on leg 1. Do you read ~5v on each of them? Do NOT allow the probe to short to the clamps or anything else.
I don't have the voltages for those.
Are you sure that the driver board is OK?
Ok, Perry I got her all fixed up but wasnt easy. Voltages were all good. So what happend was I ended up having to replace the voltage regulators and had them installed opposite. (rookie mistake I know) then powered it up and it ended up going into protect mode. When they were installed opposite my guess is but im not sure that it somehow disabled the protection circuit. After immediately going into protect mode I checked the transistors on the driver board and sure enough Q6 was shorted. Upon replacing that I powered it up but got absolutely nothing. Checked the driver board again everything was perfect. After hours of checking the schematic provided by Brandes.cm I was able to discover Q3 and Q4 ended up burning up on the power board, a driver transistor located at q7A was shorted and also the remote lead connection was shorted due to a burnt ceramic disk capacitor at C2. Any guesses to what may have caused these? Completelty stumped but somehow these shorted out in the process. Maybe a power surge or something... Anyways im really happy I got it fixed. My first repair beyond the simple blown mosfets and resistors. I appreciate your valuable input alot!
The driver was damaged when the FETs failed. There isn't any way for Q3 and Q4 to fail from the failure of the power supply. I'd guess that they failed when they were being tested and the probes slipped/shorted between terminals.
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