I have a power transformer 273-1385B
input 120 vac 60 Hz --> output 12.6 vac 60 hz
max output current I believe can be 300mA
typical is 80mA
Primary is plugged into the house 120 vac 15 amp wall circuit .
When I measure the secondary side with a digital multimeter I get approx 16 volts ac +- .5 volts or so. I have my multimeter set correctly to ac. So my question is I would think the value should be closer to 12.6 as the transformers ratings say on the side of the transformer. ( I am getting more voltage! Is this a typical tolerance kind of like a resistors tolorance or something???)
Now when I put a full bridge rectifier on the secondary coils of the transformer rated at 4amp 50volts (which is the only rectifer I had but definitely well over the ratings of the transformer so I am ok to use it)
I am just wondering when I measure the dc I get it dropping a approx 1 volt from the rms 16 volts ac before the rectifer?
So it seems like a retifier has some resistance to it? Superized that it has so much resistance but this could be because the ac was measured in RMS where as the dc was measure normally?
Either way my multimeter reads around the same value for the dc of the rectified ac? I would think my multimeter would flucuate between 0 and 15 volts ??? So does this full wave bridge rectifier also act as a regulator ???
Could it be that this rectifer smooths dc as well as converts it from ac to dc? The part is 276-1146 radioshack.
If it's still pulsating dc then why am I not seeing the dc changing on my multimeter?
Read below if it is pulsating dc
Ok , if it is pulsating dc I have a 12 volt voltage regulator but it says on the back it's
input voltage 35V
Operating temp 0 C - 70 C
Max junction temp 150 C
It is a voltage regulator 7812 from radioshack part 276-1771
Can I stick this regulator in front of the rectifier or do I need a 35 V operation source <--(or will the 15 volt be ok to run it on )
If that is not going to work then I have some high rated , high capacitance capacitors wondering how high I would need the capacitance to be to make the dc smooth ?
input 120 vac 60 Hz --> output 12.6 vac 60 hz
max output current I believe can be 300mA
typical is 80mA
Primary is plugged into the house 120 vac 15 amp wall circuit .
When I measure the secondary side with a digital multimeter I get approx 16 volts ac +- .5 volts or so. I have my multimeter set correctly to ac. So my question is I would think the value should be closer to 12.6 as the transformers ratings say on the side of the transformer. ( I am getting more voltage! Is this a typical tolerance kind of like a resistors tolorance or something???)
Now when I put a full bridge rectifier on the secondary coils of the transformer rated at 4amp 50volts (which is the only rectifer I had but definitely well over the ratings of the transformer so I am ok to use it)
I am just wondering when I measure the dc I get it dropping a approx 1 volt from the rms 16 volts ac before the rectifer?
So it seems like a retifier has some resistance to it? Superized that it has so much resistance but this could be because the ac was measured in RMS where as the dc was measure normally?
Either way my multimeter reads around the same value for the dc of the rectified ac? I would think my multimeter would flucuate between 0 and 15 volts ??? So does this full wave bridge rectifier also act as a regulator ???
Could it be that this rectifer smooths dc as well as converts it from ac to dc? The part is 276-1146 radioshack.
If it's still pulsating dc then why am I not seeing the dc changing on my multimeter?
Read below if it is pulsating dc
Ok , if it is pulsating dc I have a 12 volt voltage regulator but it says on the back it's
input voltage 35V
Operating temp 0 C - 70 C
Max junction temp 150 C
It is a voltage regulator 7812 from radioshack part 276-1771
Can I stick this regulator in front of the rectifier or do I need a 35 V operation source <--(or will the 15 volt be ok to run it on )
If that is not going to work then I have some high rated , high capacitance capacitors wondering how high I would need the capacitance to be to make the dc smooth ?
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