Hi
for 800W at 8R load supply should be +80v/10A -80v/10A. It is quite normal if you get 73v on clip at high level (normal power)increase current will can goes up to rail volt.
Regards
MANOJ
Hi monoj
My load is 4 ohms not 8
Hi,
sq.root (WxR)
Sq.root (800wx4R)=Sq.root(3200)=56.57v DC so you need +/-57v 14A for 800w 4R load
Regards
MANOJ
sq.root (WxR)
Sq.root (800wx4R)=Sq.root(3200)=56.57v DC so you need +/-57v 14A for 800w 4R load
Regards
MANOJ
Hello dear
thank you again for your replies
I know all these and that's whty I'm wondering about output power
as I apply a 100 Hz sine wave I get a sine wave With only 70 V peak voltages and after that I get clipping (at this point my smps rail voltages are at +-85V dc)
my smps is capable of delivering more than 1600W rms (test it with resistive load for a long period of time
thank you again for your replies
I know all these and that's whty I'm wondering about output power
as I apply a 100 Hz sine wave I get a sine wave With only 70 V peak voltages and after that I get clipping (at this point my smps rail voltages are at +-85V dc)
my smps is capable of delivering more than 1600W rms (test it with resistive load for a long period of time
HI,
already +/-73v DC @ full load peak (+/-85v DC supply)
Regards
MANOJ
73Vpeak/1.414=51.6Vrms
51.6*51.6/4ohm=664W rms.
already +/-73v DC @ full load peak (+/-85v DC supply)
Regards
MANOJ
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"I apply a 100 Hz sine wave I get a sine wave With only 70 V peak voltages"
70vrms sqd / 4r = 1225wrms yes?
70vrms sqd / 4r = 1225wrms yes?
my smps is capable of delivering more than 1600W rms
Hi,
what type of wire i mean gauge used SMPS supply connected to your AMP 1mm Sq. or 2mm Sq.
Min. req. 2.5mm Sq. wire for +/- & GND If it is not increase wire gauge and test. for low wire gauge will produce more EMI and you won't get result
can you provide a picture
Regards
MANOJ
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"I apply a 100 Hz sine wave I get a sine wave With only 70 V peak voltages"
70vrms sqd / 4r = 1225wrms yes?
Yes
1225W peak power"I apply a 100 Hz sine wave I get a sine wave With only 70 V peak voltages"
70vrms sqd / 4r = 1225wrms yes?
70/1.414=49.5V
(49.5*49.5)/4=612W rms
Hi,
what type of wire i mean gauge used SMPS supply connected to your AMP 1mm Sq. or 2mm Sq.
Min. req. 2.5mm Sq. wire for +/- & GND If it is not increase wire gauge and test. for low wire gauge will produce more EMI and you won't get result
can you provide a picture
Regards
MANOJ
I use 1mm wire for connections but the length of wires are about 50cm
and I also take my voltage reading from both smps output and from mosfet pins on amplifier and the differnece is not that much
but I will definetely try using even 4mm gauge tonight and will share the result here
I will also share my setup
I design a new pcb for the amp and get it running but the result with the output voltage is the same as your pcb design
Is it a final schematic and a pcb for sharing?
I'm still working on the Dc protection board and I plan to mount it in top of the amp
I could only get 600W from this amp so far
I will share the pcb as soon as its ready
HI,
already +/-73v DC @ full load peak (+/-85v DC supply)
Regards
MANOJ
73V peak at the output. it's not any +/- DC voltage there.
73V peak = 51.6Vrms
52.6*51.6/4ohm=665Wrms. not 1300+.
thank you for your reply
I solve that problem and now the amp working perfect but I want to get about 800W rms but I can not go higher than 600W
does that 12V chips supply cause this and I get only 73V dc(the rail voltages are at 85V DC) on mosfets at full power?
Should I increase power supply voltages?
800W 8 ohm RMS you will need supply more than 90Vdc. Means need higher mosfet and new setting.
It is not simply 80V x 10A = 800W because the amp cannot produce 80V out RMS with just 80V rails.
For me, put factor 0.9 x 0.707 to get RMS from a voltage rails for class D amp. Then consider 8 ohm load. There you will get amps load. Then RMS watt
800W 8 ohm RMS you will need supply more than 90Vdc. Means need higher mosfet and new setting.
It is not simply 80V x 10A = 800W because the amp cannot produce 80V out RMS with just 80V rails.
For me, put factor 0.9 x 0.707 to get RMS from a voltage rails for class D amp. Then consider 8 ohm load. There you will get amps load. Then RMS watt
But my subwoofers are 4 ohms
and even with 0.9 factor I should get around 720W on 4 ohms
Hi,
your output volt was +/-73v peak 1KHz sine (73v pp) with load 4R. and 70vpp on 100Hz
so you will get more than 600W.
Ex. {A 100W inverter will load Incandescent 100W bulb, but the engineer said it is 60W only they calculate the power factor 0.6 and said the final watt.}
Regards
MANOJ
your output volt was +/-73v peak 1KHz sine (73v pp) with load 4R. and 70vpp on 100Hz
so you will get more than 600W.
Ex. {A 100W inverter will load Incandescent 100W bulb, but the engineer said it is 60W only they calculate the power factor 0.6 and said the final watt.}
Regards
MANOJ
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Hi,
Normally all branded team like Behringer, Qsc, crown etc.. set clip on (VCC - 18v) range.
85-18= 67v. In your case is 85-15=70v.
I think for setting clip level point 21v~23v for 2R load, 18v for 4R load, 15v for 8R load.
so 900W@4R you need +/-78v DC. {78-18=60vpp output @4R load}
Regards
MANOJ
Normally all branded team like Behringer, Qsc, crown etc.. set clip on (VCC - 18v) range.
85-18= 67v. In your case is 85-15=70v.
I think for setting clip level point 21v~23v for 2R load, 18v for 4R load, 15v for 8R load.
so 900W@4R you need +/-78v DC. {78-18=60vpp output @4R load}
Regards
MANOJ
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