900W H-class PA Amp with Limiter

[waylene]

I only get power on my positive rail, this is only the positive rail that warm up when I pump up some volume. The negative rail stay cold and don't warm up like the positive rail. Is there any ting you can think of what can be the problem on it?

 

[waylene]

I only get power on my positive rail, this is only the positive rail that warm up when I pump up some volume. The negative rail stay cold and don't warm up like the positive rail. Is there any ting you can think of what can be the problem on it?

 

[AndrewT]

disconnect the Amp from the PSU.

Check the PSU thoroughly.

 

[waylene]

Hi AndrewT I all ready to that two times, there is power on the amp. When I take of fuse on Negative rail, amp is still playing on with out the fuse.

 

[waylene]

You see here, I use one trapo here that give out +70 +45 0V -70 -45 volt dc out. I use this trapo for only testing the amp.

 

[AndrewT]

you have checked the PSU.
You have connected the amplifier.
the amplifier does not work.
Then either the connections are wrong, or the amplifier is wrong.

 

[waylene]

You see here sir? Where I mark with green, this positive rail warm up when I pump up some volume, but the negative rail where I mark with red, never switch on, transistor stay cold and never warm up.

 

[sandman15th]

I only get power on my positive rail, this is only the positive rail that warm up when I pump up some volume. The negative rail stay cold and don't warm up like the positive rail. Is there any ting you can think of what can be the problem on it?

Please check or How much voltage that u get on the fuses? It must the same voltage,then when u put high volume the voltage must increase..

 

[gantex]

You see here sir? Where I mark with green, this positive rail warm up when I pump up some volume, but the negative rail where I mark with red, never switch on, transistor stay cold and never warm up.

im not see any wrong here, or i cannot see? First clean the bottom cooper then Try to replace IR2117 on + rail with IR2117 on - rail, just to check if this both IC is OK. I hope this work.

Regard.

 

[JOHN BALI]

Hi, Waylene,
this is good suggestion

im not see any wrong here, or i cannot see? First clean the bottom cooper then Try to replace IR2117 on + rail with IR2117 on - rail, just to check if this both IC is OK. I hope this work.

Regard.

Clean the bottom, then try to put other IR2117 from working amp... Maybe the IR2117 not doing the job, I have someone here warning about IR2117.
He have bad IR2117 that can oscillate by itself...
If changing them don't solve the problem, maybe you have broken trace or broken transistor, check 2N5401-2N5551 MJE340-350
or you can try to measure the voltage on each base to ground... If you find different more than 10%(positive & negative side) then you will start to find where is your problem

 

[waylene]

Hi John, Thanks for helping me solve the problem on H900. I will do so what you told me to do! But if there is power on amp, why only part of the amp will play? I power amp up only with 55v 0 55v dc, but still get sound out on one side of channel. It's look for me like it is b500 that play now, with out 110v 0 110v dc. Why amp still play sound with out 110v 0 110 dc ? I don't gonna give up that amp, I will fix them, it cost me a lot of money to buy the parts.

But Thanks for help me try solve it.

Cheers!!!

Warren.

 

[JOHN BALI]

Amp will still play without 110 high rail, but you get B500 playing not the H900...
so the problem is at the stepper circuit...

you can post "close up" picture(top & bottom side) of stepper circuit that has problem. So easier to us to help you...

Cheers..

 

[waylene]

Can you show me here were stepper driver side is on the h900, I'm must be honest with you, I'm learner and try to learn my self my friend. Here I stay, nobody are good with electronics here. I'm the only one who suffer from help if something goes wrong here. That's why I appreciated so much from every one here on DIY AUDIO who help me solve my problems.

 

[AndrewT]

learner or beginner?

A beginner should never have started an H900 build !!!!!!

 

[waylene]

Andrew T. I build the B500 my self, with the help of Sir Jay Irvyne, and the problem there was a small ting, I did not rite, and he help me solve that. There it play loud and clear with out any problems on it.

 

[waylene]

Can you mark here on the pic, where I must look for fault and what I must do my friend? I hope I never waste your time. If you can send me a email address of you, I will post better pics for you.

 

[waylene]

If I got H900 at 100% rite, I will go for a bigger one, may be 1000watt amp. So I will learn from every one of you. You guys are my hero in Electronics, and that's why I love you guys.

 

[JOHN BALI]

btw this amp use special power supply... (on your picture it is only 3 power wire for PGND, +110 & -110)
Please, let we see your power supply too

You must connect all the 5 power wire PGND, +55, +110, -55, -110, & also for testing I also usually connect input to SGND & to PGND with separate wire.
Use bulb tester too, so you know when it will fail before it's really fail ...

 

[waylene]

Thanks a lot John I will send pics of power supply.

 

[gantex]

If H900 goes to HV on first start, i suspect any wrong with mosfet connection or maybe something wrong here. Just for fast correction, can u shared pcb layout u made, and show all pic stepper, include bottom too. Stepper position on end left and right of ur pcb, please give this pic.