if the amp work without problem,and voltage of the ic is stable 15vdc -/+ then use 5watts resistor..
today i changed the resistors to 5w 3.3k. but with 53vdc it is normal hot. for the 80vdc its getting very hot. i cant understand why is this getting hot.
i checked the volatges across the zeners it shows 15.2,15.1vdc.
22ohm resistor across shows .65v.
dc offset is .90v.
i am getting very angry for this problem.
i checked the volatges across the zeners it shows 15.2,15.1vdc.
22ohm resistor across shows .65v.
dc offset is .90v.
i am getting very angry for this problem.
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There is no problem, disipation is normal P=U2/R, with increase voltageX2 you have increase power(disiparion)X4.
Voltage on resistor is 80V-15V (on zener)=65V, P=(65X65)/3300 = 1,28W and resistor getting hot.
please reduce the image until it fits with the parts size.
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5W wire-wound sandblock resistors can withstand temperatures over 100°C. Let's say the 'normal' working temperature would be around 70-80°C . What does hot mean? Your body temperature is around 36°C which means, a 5W resistor under normal working condition should be hot. Little philosophy here. If you have a lab thermometer simply attach the probe and do a measurement 😉 If you don't have one, I recommend you to buy one. It's simply a must and for every electronic hobbyist.
Digital Scientific Thermometer 2 K-Type Sensors DT804A | eBay
Digital Scientific Thermometer 2 K-Type Sensors DT804A | eBay
You must build DC/DC inverter to get +/-55V from 12V, and any amp can be used as car amp.
Mile, I will be assembling protect pcb today, But I have still Not understood where does BD 241c exactly connect to the pcb.
BD241C is used as thermal sensor diode (B,C shoted-anode and E-catode) mountage on heatsink with outputs.
i have done it in photoshop. the finished pcb is not real i just made it look finished and real.
Relay for protect I have 24v 1ck, Shopkeeper told it is 16 amp and 1ck is one changeover is it fine to use.
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