HI a little suggestion, with psu with 39Vdc under 2A bios and a choke what vfet SE can be done ?
While 300 W light bulbs can be hard to find it should be easy to find 250W heat lamps in either clear or red !
HI thanks for your time...I only have pushpull set of sony from acroman
Which R is this? Vcc you mean the voltage from your PSU? If I get this right ou mean the R from lamps? This is not very accurate. Anyway I use the drop on Rs, which gives me very good results.
For CPU water cooling, if you mean an AIO, it will do the job upto 150W.
problems
ok i finish the amp, include heatsink and big power supply.
all the power is floating, no ground (chassis).
when i plug an input from the pc, the Depreciation relay of the hose is pop out.
now the sound card is gone bad,maybe because the amplifier is floating power?
another problem, when i connected the ground (chassis) to the GND of the circuit, one of the SIT gone bad
ok i finish the amp, include heatsink and big power supply.
all the power is floating, no ground (chassis).
when i plug an input from the pc, the Depreciation relay of the hose is pop out.
now the sound card is gone bad,maybe because the amplifier is floating power?
another problem, when i connected the ground (chassis) to the GND of the circuit, one of the SIT gone bad
You may have destroyed your card because of the thump of the death of your SIT.
Remember I have told you that you need to use SiCs till system is stabilized... Use UJ3N065080K3S and when system is stabilized then put your SITs on.
Also, remember to disconnect input and output during start up and shutdown.
Search the forum how to properly connect GND to chassis, starting from a 6 Ohm power resistor, c capacitor and a bridge.
Remember I have told you that you need to use SiCs till system is stabilized... Use UJ3N065080K3S and when system is stabilized then put your SITs on.
Also, remember to disconnect input and output during start up and shutdown.
Search the forum how to properly connect GND to chassis, starting from a 6 Ohm power resistor, c capacitor and a bridge.
Plugging the input while the amp was live probably caused a spike in the gate voltage which exceeded the SIT's Vgs limit. The SIT failed and essentially shorted out the power supply. A zener diode across the gate/source terminals is a good idea.
Also, a fuse in the power supply circuit is better than relying on your house circuit breaker.
Also, a fuse in the power supply circuit is better than relying on your house circuit breaker.
the amp work fine after the sound card is gone bed.
i build the amplifier first from cheap SIT and variable PS, then i connected the expensive SIT, and all works fine.
when i recognized the sound card problem, i connected to chassis, but then the Depreciation relay of the hose is pop out.
maybe the main problem is that the GND is not 0v, and the GND of the line in is 0v?
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That's a pretty good bet! It sounds like you are lucky that you've not been zapped by this. I would unplug it, and use an ohmmeter connected to chassis, and see what part of the amplifier is accidentally grounded to it.
I took a few steps back.
connected only the transformer to bridge and caps.
if the chassis is not connected, all good
if the chassis is connected trough thermistor (or directly), Depreciation relay of the hose is pop out.
connected only the transformer to bridge and caps.
if the chassis is not connected, all good
if the chassis is connected trough thermistor (or directly), Depreciation relay of the hose is pop out.
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Is your chassis grounded to the ac line ground ? It look like you have a short somewhere between your b+ and your chassis and that your chassis is not grounded. If so, you have some voltage on your chassis. Be safe and unplugged everything until you have found the short and that your chassis is grounded directly to the ac line ground