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The MAX71020 is a single-chip, analog front-end to be used in high-performance revenue meters. It contains the compute engine found in Maxim’s fourth-generation meter SOC and an improved ADC, and interfaces to the host microcontroller of choice over a SPI interface.
MAX71020 Single-Chip Electricity Meter - [Link]
This video covers the basics of diodes, bridge rectifiers, and how to build simple unregulated AC to DC power supplies than can handle a few mA up to several Amps. Diode Tutorial & How to build an AC to DC power supply - [Link]
With current transformers, you can measure AC current simply and with a sufficient accuracy, moreover with maintaining of a high safety level thanks to a galvanic isolation.
General purpose AC current measurment, overload and shortcut protection, load drop or shutdown detection and similar application require simple and reliable solution. Current transformers meet all these requirements and they add further bonuses like galvanic isolation, no intervention to a measured circuit and a convenient price.
As we know, one of AC current measurement methods is based on the usage of a current transformer. Alternating magnetic field around a wire lead, which in a continual proportion to a current flowing through a wire, will induce an AC voltage in a measurement transformer. At a suitable construction and a right transformer loading, is the output voltage in a continual proportion to a current in a measured lead. Perhaps the biggest advantage of this method is the fact, that a measuring circuit is galvanically isolated from a measured lead and at the same time, the transformer doesn´t indtroduce any added load neither any influence. If we´d like to go to a detail, the transformer consumes a negligible amount of energy of few tens of mW/10A from a measured lead, which is being lost in the winding and a load of the transformer.
Every current transformer is designed for a certain load, i.e. at a certain load it provides most accurate results. For example for the type AC-1050 it is 100 Ohms. In such a case is valid a transfer ration 1000:1, i.e. to the load flows a 10 mA current at a 10A current in a measured lead. It means, that on a 100 Ohm we will measure a voltage with a value of 1V. Output of a current transformer can be connected to a panel meter, digital voltmeter, oscilloscope or an AD converter input. By using an AD converter, it is also possible to monitor a course of a current and to discover various nonlinearities in a power consumption.
Talema current transformers are top quality components with an outstanding quality / price ratio. Transformers are designed for soldering into a PCB. In our offer you can find more types, up to 100A maximum current. Currently we can offer you type AC 1050 also from the producer´s stock (ca. 8000 pcs) with 1-2 weeks delivery time (standard delivery time uses to be 20 weeks). Detailed information will provide you datasheets at given types.
Precise and price-convenient measuring of AC current - [Link]
mrx23dot.blogspot.com writes:
“UPB communication is a method of reliably communicating command, control, and status information across an electrical AC powerline. Because of its low cost and high reliability characteristics, the UPB communication method is ideally suited for command and control applications in both the residential and commercial markets. “ – For further details please refer to UPB Description.
One of its disadvantages it has only widely spreaded in the US (120VAC 60Hz). This article focuses on the European (230VAC 50Hz) electrical network, but with a little firmware modification it is possible to adapt it to the US mains. The price of an UPB device is around $80-$100, with this article you can build it from ~$8.
Cloning the UPB home automation system - [Link]
electronixandmore.com writes:
My variable AC power supply has gone through several revisions over the years. It started out as a simple unenclosed variac (variable autotransformer) and electrical outlet mounted on a block of wood. I eventually put it in the case of what used to be an old audio signal generator for safety and appearance. Among the other added features, I used a 0-250VAC analog meter that I had on hand to display the output voltage because otherwise it was annoying to whip out the multimeter to monitor the voltage coming out of the variac. Over the years I realized that the meter was inaccurate and simply useless, so a new readout was necessary.
Digital AC Voltmeter - [Link]
AC vs. DC – [Link]
schazamp built an FSAR001 experimenter board: [via]
This device, remember, takes 80-265Vrms wall power and puts out a (relatively) clean 5V DC. According to the datasheet, the way this thing works is by monitoring the voltage of the AC waveform and charging a big electrolytic capacitor during the low voltage segments on the leading and trailing edge of the (half-rectified) wave. The controller then discharges the capacitor to sustain the 5V DC. It claims it can handle a maximum load of 35mA
Be careful working with unisolated AC voltage, that stuff will kill you in an instant. We don’t do it.
FSAR001 AC to 5volt DC regulator – [Link]
Fileark writes:
I decided it would be easiter to explain AC and DC current if the user already knew how to use and oscilloscope. Explaining how to use an oscilloscope is easy if the user already knows what DC and AC current is. I think the video worked out as a fast paced tutorial for both subjects.
AC vs DC Explained and How to Use an Oscilloscope – [Link]
Citizen Electronics Co., Ltd. recently reported having developed the LMC10B series of LED lighting modules with built-in AC drive circuits using innovative circuit technology.
LEDs are usually driven by DC (direct current) power supply. Where an AC (alternating current) power supply is used, a DC converter circuit is needed. Issues to be resolved with DC power driven LEDs include the complexity of the circuit increasing the number of components, and electrical noise generated. [via]
AC powered 22 watts 1000 lumen LED module – [Link]
This article discuss how AC motors work. AC motors are a little bit different from DC motors as they don’t require brushes and the speed is controlled by frequency instead of voltage. Check how they work on the link below.
How AC Motor works – [Link]
