I always thought they are unipolar. But when I compared that my variable power supply only made an amp module work with + and - connected instead of + and gnd or - and gnd. And when I used regular 12vdc power adopters they also powered the circuit.
i built a small lm386 amplifier. on the schematic it said +12v and gnd. but it dint work when i hooked up only Positive and ground on power supply. untill i hookep ground from circuit to power sipply's negative terminal.
very confused
very confused
Bipolar power adapters are scarce as hens' teeth. Without knowing more about the power supply and amplifier circuits it's hard to clear any confusion.
Unipolar. It outputs 0-30 DC volts between the positive and negative terminals. The manual isn't explicit, but it appears the ground terminal has no internal connection and so can be wire linked to either + or - terminal as desired.
Hope this helps clear things for you.
Unipolar. It outputs 0-30 DC volts between the positive and negative terminals. The manual isn't explicit, but it appears the ground terminal has no internal connection and so can be wire linked to either + or - terminal as desired.
Hope this helps clear things for you.
There is often a shorting link permanently attached to the Green terminal.
That shorting link can be connected to either the Red or the Black terminal.
Whichever (Red or Black) is connected to Green is then grounded to EARTH.
If the shorting link is left "dangling", neither the Red, nor the Black, are connected to EARTH.
The output is then isolated from EARTH.
But in the meantime, there is 0Vdc to 30Vdc DIFFERENCE available between Red and Black.
It is unipolar. Red is always more positive than Black, or equally valid Black is always more negative than Red.
That shorting link can be connected to either the Red or the Black terminal.
Whichever (Red or Black) is connected to Green is then grounded to EARTH.
If the shorting link is left "dangling", neither the Red, nor the Black, are connected to EARTH.
The output is then isolated from EARTH.
But in the meantime, there is 0Vdc to 30Vdc DIFFERENCE available between Red and Black.
It is unipolar. Red is always more positive than Black, or equally valid Black is always more negative than Red.
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Starting to get it now. So bipolar is similar to 2 phase in electrical? (I'm very familiar with electricity, used to work as a helper and studies electrical codes and theories etc, but electronics is new for me).
Just slightly. Bipolar here means that there are two ground referenced poles, one positive and one negative. 2-phase ac is waveforms 90 degrees apart, referenced to each other.
?
The USA and Canada use a split supply from a centre tapped transformer for domestic supplies.
The Centre Tap becomes the Neutral. The other two tappings become the two 110/120Vac that enter the house as a 3 wire supply (two Live and one Neutral).
Appliances that require 220/240Vac get connected to BOTH live feeds.
Appliances that require 110/120Vac get connected to ONE live feed and Neutral.
The socket outlets use this 110/120Vac distribution.
I believe there are different socket that distribute 220/240Vac.
Q. do they "look" different?
Q. are the 220/240Vac plugs incompatible with the 110/120Vac sockets?
Q. do 220/240Vac appliances also get connected to Neutral as well as to Earth? i.e. 4wwire connection?
The two live feeds just like any centre tapped transformer are effectively 180 degrees apart, i.e. they are out of phase.
I think I was referring to something different, 2-phase ac 90 degrees apart in the same sense as 3-phase ac 120 degrees apart.
I can attempt to answer the questions, though. 240-volt plugs and sockets are always keyed for polarity and are very different from the standard 120-volt plugs.Most residential types are 3-wire. Virtually all installations require a neutral to ground connection at the service entrance, and there are various code requirements for 240 appliances, some with a fourth wire ground and some using the neutral line. That is my understanding.
I can attempt to answer the questions, though. 240-volt plugs and sockets are always keyed for polarity and are very different from the standard 120-volt plugs.Most residential types are 3-wire. Virtually all installations require a neutral to ground connection at the service entrance, and there are various code requirements for 240 appliances, some with a fourth wire ground and some using the neutral line. That is my understanding.
2phase is 180degrees apart.
3phase is 120degrees apart.
4phase is 90degrees apart.
5phase is 72 degrees apart.
etc.....
3phase is 120degrees apart.
4phase is 90degrees apart.
5phase is 72 degrees apart.
etc.....
So when there's a schematic that has just + and ground than it's actualy + and -. Unless there's vcc and vdd or vs etc than it's bipolar ?
A circuit using a bipolar supply should clearly show the + and - voltage connections. For schematics with just + and ground, yes you can think of it as + and -. Don't, though, get too wrapped up with Vcc, Vdd, +, -, etc yet. Understand that voltage is a difference in electrical potential between points. Ground is a reference point. And there are standards and conventions for expressing those on paper.
It goes against convention, but in your LM386 schematic, pin 6 could be designated "ground" and pin 4 could be designated -6vdc... the circuit will work the same.
It goes against convention, but in your LM386 schematic, pin 6 could be designated "ground" and pin 4 could be designated -6vdc... the circuit will work the same.
Source voltage, Drain voltage, Collector voltage, Emitter voltage, etc.
Referring to transistors, but often loosely applied to power supplies in general.
Referring to transistors, but often loosely applied to power supplies in general.
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