Friday, August 27, 2010

Karakteristik Beberapa Jenis Bahan Penghantar Listrik

Seperti telah kita ketahui, bahwa untuk pelaksanaan penyaluran energi listrik dapat dilakukan dengan dua cara, yaitu berupa saluran udara dan kabel tanah. Pada saluran Udara, terutama hantaran udara telanjang biasanya banyak menggunakan kawat penghantar yang terdiri atas: kawat tembaga telanjang (BCC, singkatan dari Bare Cooper Cable), Aluminium telanjang (AAC, singkatan dari All Aluminium Cable), Campuran yang berbasis aluminium (Al-Mg-Si), Aluminium berinti baja (ACSR, singkatan dari Aluminium Cable Steel Reinforced) dan Kawat baja yang berisi lapisan tembaga (Cooper Weld).

Sedangkan pada saluran kabel tanah, biasanya banyak menggunakan kabel dengan penghantar jenis tembaga dan aluminium, perkembangan yang sangat dominan pada saluran kabel tanah adalah dari sisi bahan isolasinya, dimana pada saat awal banyak menggunakan isolasi berbahan kertas dengan perlindungan mekanikal berupa timah hitam, kemudian menggunakan minyak ( jenis kabel ini dinamakan GPLK atau Gewapend Papier Lood Kabel yang merupakan standar belanda dan NKBA atau Normal Kabel mit Bleimantel Aussenumheullung yang merupakan standar jerman, dan jenis bahan isolasi yang terkini adalah isolasi buatan berupa PVC (Polyvinyl Chloride) dan XLPE (Cross-Linked Polyethylene). Jenis bahan isolasi PVC dan XLPE pada saat ini telah berkembang pesat dan merupakan bahan isolasi yang andal.

Di waktu yang lalu, bahan yang banyak digunakan untuk saluran listrik adalah jenis tembaga (Cu). Namun karena harga tembaga yang tinggi dan tidak stabil bahkan cenderung naik, aluminium mulai dilirik dan dimanfaatkan sebagai bahan kawat saluran listrik, baik saluran udara maupun saluran kabel tanah. Lagipula, kawat tembaga sering dicuri karena bahannya dapat dimanfaatkan untuk pembuatan berbagai produk lain.

Suatu ikhtisar akan disampaikan dibawah ini mengenai berbagai jenis logam atau campurannya yang dipakai untuk kawat saluran listrik, yaitu:

• Tembaga elektrolitik, yang harus memenuhi beberapa syarat normalisasi, baik mengenai daya hantar listrik maupun mengenai sifat-sifat mekanikal.

• Brons, yang memiliki kekuatan mekanikal yang lebih besar, namun memiliki daya hantar listrik yang rendah. Sering dipakai untuk kawat pentanahan.

• Aluminium, yang memiliki kelebihan karena materialnya ringan sekali. Kekurangannya adalah daya hantar listrik agak rendah dan kawatnya sedikit kaku. Harganya sangat kompetitif. Karenanya merupakan saingan berat bagi tembaga, dan dapat dikatakan bahwa secara praktis kini mulai lebih banyak digunakan untuk instalasi-instalasi listrik arus kuat yang baru dari pada menggunakan tembaga.

• Aluminium berinti baja, yang biasanya dikenal sebagai ACSR (Aluminium Cable Steel Reinforced), suatu kabel penghantar aluminium yang dilengkapi dengan unit kawat baja pada inti kabelnya. Kawat baja itu diperlukan guna meningkatkan kekuatan tarik kabel. ACSR ini banyak digunakan untuk kawat saluran hantar udara.

• Aldrey, jenis kawat campuran antara aluminium dengan silicium (konsentrasinya sekitar 0,4 % – 0,7 %), Magnesium (konsentrasinya antara 0,3 % - 0,35 %) dan ferum (konsentrasinya antara 0,2 % - 0,3 %). Kawat ini memiliki kekuatan mekanikal yang sangat besar, namun daya hantar listriknya agak rendah.

• Cooper-weld, suatu kawat baja yang disekelilingnya diberi lapisan tembaga.

• Baja, bahan yang paling banyak digunakan sebagai kawat petir dan juga sebagai kawat pentanahan.

Berdasarkan ikhtisar diatas, dapat dikatakan bahwa bahan yang terpenting untuk saluran penghantar listrik adalah tembaga dan aluminium, sehingga kedua bahan tersebut banyak digunakan sebagai kawat pengantar listrik, baik saluran hantar udara maupun kabel tanah.

Untuk pembahasan lebih detail mengenai bahan penghantar listrik, dapat dibaca pada artikel berikut:

“Ilmu Bahan Listrik Dasar” , "Konduktor" dan “Electrical Power Cable Engineering”

atau kunjungi label artikel: "Ilmu Bahan Listrik"

Semoga bermanfaat,
Sumber: “Distribusi dan Utilisasi Tenaga Listrik” – Abdul Kadir.

Saturday, August 21, 2010

Anti Theft Car wireless alarm

This is anti theft alarm with wireless connectivity ,called Anti Theft Car wireless alarm The FM radio-controlled anti- theft alarm can be used with any vehicle having 6- to 12-volt DC supply system. The mini VHF, FM transmitter is fitted in the vehicle at night when it is parked in the car porch or car park. The receiver unit with CXA1019,
Anti Theft Car wireless alarm
a single IC-based FM radio module, which is freely available in the market at reasonable rate, is kept inside. Receiver is tuned to the transmitter's frequency. When the transmitter is on and the signals are being received by FM radio receiver, no hissing noise is available at the output of receiver. Thus transistor T2 (BC548) does not conduct. This results in the relay driver transistor T3 getting its forward base bias via 10k resistor R5 and the relay gets energised. When an intruder tries to drive the car and takes it a few metres away from the car porch, the radio link between the car (transmitter) and alarm (receiver) is broken. As a result FM radio module gene-rates hissing noise. Hissing AC signals are coupled to relay switching circ- uit via audio transformer. These AC signals are rectified and filtered by diode D1 and capacitor C8, and the resulting positive DC voltage provides a forward bias to transistor T2. Thus transistor T2 conducts, and it pulls the base of relay driver transistor T3 to ground level. The relay thus gets de-activated and the alarm connected via N/C contacts of relay is switched on. If, by chance, the intruder finds out about the wireless alarm and disconnects the transmitter from battery, still remote alarm remains activated because in the absence of signal, the receiver continues to produce hissing noise at its output. So the burglar alarm is fool-proof and highly reliable.

Game Show Timers Schema electronic Circuit





Many people have expressed an interest in the game show timer from the "end user" viewpoint instead of the "hobbyist" viewpoint. These interested folks don't have much electronic assembly experience but they are highly motivated and are willing to give it a try in order to get the end result. It is with these people in mind that the following circuit was developed. This is my favorite and the one I recommend.

Here is a really simple game show timer designed with the beginner in mind! The power source is an ordinary 12 volt lantern battery or battery pack made up of C or D cells. The lamps may be ordinary flashlight bulbs; the prototype uses 750 mA Krypton types (KPR112) with wires soldered directly onto the bulbs. The control devices may be just about any non-sensitive gate SCRs or triacs with a current rating of a few amps. Avoid SCRs that trigger with 100s of microamperes; you want a gate trigger current of a few mA or else you will have trouble with more than one light coming on at once. A low value resistor, perhaps 470 ohms may be added from gate to -12 volts to reduce false triggering.

SCRs are shown and triacs may be substituted by connecting MT1 to the negative battery terminal and MT2 to the lamps. In fact, the two types of devices could probably be mixed if that is what the junk box has to offer! (But not sensitive gate types!) The zener is an ordinary 9 volt, 1 watt type like the 1N4739. The 100 ohm resistor may be any type with a rating of 1/8 watt or more. The reset/power button is an ordinary toggle switch and the pushbuttons are any convenient normally-open type

Electronic Circuit Symbols Components




Circuit diagrams appearance how cyberbanking apparatus are affiliated together. Anniversary basic is represented by a attribute and a few are apparent here, for added symbols amuse see the Ambit Symbols page.

Circuit diagrams and basic layouts

Circuit diagrams appearance the access as acutely as accessible with all affairs fatigued neatly as beeline lines. The absolute blueprint of the apparatus is usually absolutely altered from the ambit diagram and this can be ambagious for the beginner. The abstruse is to apply on the connections, not the absolute positions of components.

The ambit diagram and stripboard blueprint for the Adjustable Timer activity are apparent actuality so you can see the difference.








A ambit diagram is advantageous back testing a ambit and for compassionate how it works. This is why the instructions for projects accommodate a ambit diagram as able-bodied as the stripboard or printed ambit lath blueprint which you charge to body the circuit.

Drawing ambit diagrams

Drawing ambit diagrams is not difficult but it takes a little convenance to draw neat, bright diagrams. This is a advantageous accomplishment for science as able-bodied as for electronics. You will absolutely charge to draw ambit diagrams if you architecture your own circuits.

Follow these tips for best results:

Make abiding you use the actual attribute for anniversary component.

Draw abutting affairs as beeline curve (use a ruler).

Put a 'blob' () at anniversary alliance amid wires.

Label apparatus such as resistors and capacitors with their values.

The absolute (+) accumulation should be at the top and the abrogating (-) accumulation at the bottom. The abrogating accumulation is usually labelled 0V, aught volts.

If you are cartoon the ambit diagram for science amuse see the area about cartoon diagrams the 'electronics way'.

If the ambit is complex:

Try to align the diagram so that signals breeze from larboard to right: inputs and controls should be on the left, outputs on the right.

You may omit the array or ability accumulation symbols, but you charge accommodate (and label) the accumulation curve at the top and bottom.

Drawing ambit diagrams the 'electronics way'

Circuit diagrams for electronics are fatigued with the absolute (+) accumulation at the top and the abrogating (-) accumulation at the bottom. This can be accessible in compassionate the operation of the ambit because the voltage decreases as you move bottomward the ambit diagram.

Circuit diagrams for science are commonly fatigued with the array or ability accumulation at the top. This is not wrong, but there is usually no advantage in cartoon them this way and I anticipate it is beneath accessible for compassionate the circuit.

I advance that you consistently draw your ambit diagrams the 'electronics way', alike for science!

[I achievement your science abecedary won't apperception too much!]

Note that the abrogating accumulation is usually alleged 0V (zero volts).

This is explained on the Voltage and Current page.

Dome light dimmer With delay for Cars

Intro & abnegation

For all you guys out there that appetite a crumbling arch ablaze (aka address ablaze aka theatre lighting) after accepting to pay for one, you can body your own. I accept absorbed the schematics and you can body it for a few bucks accustomed that you don't accept any additional apparatus lying about contrarily it can amount you absolutely nothing. Of advance you can rip some genitalia from your TV, CD player, radio, etc., but I'm not amenable for the accident you account this way

The way it works

I won't bother you with abstruse details, but if addition is absorbed aloof let me apperceive and I'll explain in detail. For now aloof the basics. There are two stages: aboriginal one is dabbling and the additional one is fading. Back you accessible the aperture the ablaze turns on. You get central and abutting the door, but the ablaze stays on (delay stage) for an adjustable aeon of time (0-40 sec. for the ethics in the scheme, but you can calmly adapt that i.e. put a bigger capacitor) so you can see area to admit the key or do whatever you do back you get in the car, again fades abroad (fading stage) with an adjustable speed. If you affix the ACC wire (which is absolutely optional) back you about-face the key to ACC position the ablaze turns off (actually fades) alike if the dabbling date is not over (it cancels the adjournment stage).

Setup

The SR1 trimmer pot adjusts the dabbling time (the aeon that the ball is at abounding intensity) and you accept a "witness" LED that is lit during the dabbling stage; that way you can set it visually to whatever continuance you like. Back the aboriginal date ends (marked by the LED not actuality lit anymore) enters the additional date - fading. The SR2 trimmer pot adjusts the crumbling time (or acceleration if you prefer)

The angel aloft depicts how the arch ablaze about-face is usually affiliated (depending on the accomplish and archetypal of your car the affiliation may be altered in which case you'll accept to amount it out).

The angel beneath shows the schematic and the access to the arch ablaze switch.
Dome light dimmer (with delay)

Dome light dimmer (with delay) schema

Wiper Speed Control Circuits

A continuously alive wiper in a car may prove to be a nuisance, abnormally back it is not aqueous heavily. By application the ambit declared actuality one can alter across-the-board amount of the wiper from already a additional to already in ten seconds. The ambit comprises two timer NE555 ICs, one CD4017 decade counter, one TIP32 disciplinarian transistor, a 2N3055 ability transistor (or TIP3055) and a few added detached components. Timer IC1 is configured as a mono- abiding multivibrator which produces a beating back one presses
about-face S1 momentarily. This beating acts as a alarm beating for the decade adverse (IC2) which advances by one calculation on anniversary alternating alarm beating or the advance of about-face S1. Ten presets (VR1 through VR10), set for altered ethics by balloon and error, are acclimated at the ten outputs of IC2. But back alone one achievement of IC2 is aerial at a time, alone one preset (at called output) finer comes in alternation with timing resistors R4 and R5 affiliated in the ambit of timer IC3 which functions in astable mode. As presets VR1 through VR10 are set for altered values, altered time periods (or frequencies) for astable multivibrator IC3 can be selected. The achievement of IC3 is activated to pnp disciplinarian transistor T1 (TIP32) for active the final ability transistor T2 (2N3055) which in about-face drives the wiper motor at the called ambit speed. The ability accumulation for the wiper motor as able-bodied as the ambit is broke from the vehicle�s array itself. The continuance of monostable multivibrator IC1 is set for a about one additional period.

Charge Monitor For 12V Lead Acid Battery


A array is a basic aspect of any battery-backed system. In abounding cases the array is added big-ticket than the arrangement it is abetment up. Hence we allegation to accept all activated measures to conserve array life.

As per manufacturer's abstracts sheets, a 12V rechargeable lead-acid array should be operated aural 10. IV and 13.8V. Back the array accuse college than 13.8V it is said to be overcharged, and back it discharges beneath 10.IV it can be acutely discharged. A distinct accident of blackmail or abysmal acquittal can accompany bottomward the charge-holding accommodation of a array by 15 to 20 per cent.

It is accordingly all-important for all anxious to adviser the allegation akin of their batteries continuously. But, in practice, abounding of the array users are clumsy to do so because of non-avail�ability of reasonably-priced ecology equipment. The ambit abstraction presented actuality will ample this abandoned by accouterment a ambit for ecology the allegation akin of lead-acid batteries continuously. The ambit possesses two basic features:

First, it reduces the claim of animal absorption by about 85 per cent.

Second, it is a awful authentic and adult method.

Input from the array beneath analysis is activated to LM3914 1C. This activated voltage is ranked anywhere amid 0 and 10, depending aloft its magnitude. The lower advertence voltage of 10.IV is ranked '0' and the high voltage of 13.8V is ranked as '10.' (Outputs 9 and 10 are logically ORed in this circuit.) This arrangement of advertence voltages is explained later.

1C 74LS147 is a decimal-to-BCD antecedence encoder which converts the achievement of LM3914 into its BCD complement. The accurate BCD is acquired by application the hex inverter 74LS04. This BCD achievement is displayed as a decimal chiffre afterwards con�version application IC5 (74LS247), which is a BCD-to-seven-segment decoder/driver. The seven-segment LED affectation (LTS-542) is acclimated because it is accessible to apprehend compared to a bar blueprint or, for that matter, an alternation meter. The allegation cachet of the array can be bound affected from the display. For instance, if the affectation shows 4, it agency that the array is answerable to 40 per cent of its best amount of 13.8V.

The use of agenda attempt enables us to apply a buzzer that sounds whenever there is an blackmail or abysmal discharge, or there is a allegation to conserve array charge. A buzzer is active in the ambit such that it sounds whenever battery-charge avalanche to ten per cent. At this point it is recommended that accidental amount be switched off and the actual allegation be conserved for added important purposes.

Another simple combinational argumentation ambit can additionally be advised that will complete the buzzer back the affectation shows 9. Further charging should be chock-full at this point in adjustment to pre�vent overcharge.

The ambit is powered by the array beneath test, via a voltage regulator 1C. The ambit takes about 100 mA for its operation.

For calibrating the high and lower advertence levels, a agenda multimeter and a capricious adapted ability accumulation antecedent are required. For calibrating the lower advertence voltage, chase the accomplish accustomed below:

Set the achievement of ability accumulation antecedent to 10. IV.

Connect the ability accumulation antecedent in abode of the battery.

Now the affectation will appearance some reading. At this point alter preset VR2 until the account on the affectation aloof changes from 1 to 0.

The college advertence voltage is calibrated analogously by ambience the ability accumulation to 13.8V and capricious preset VR1 until account on the affectation aloof changes from 8 to 9
Charge Monitor For 12V
Charge Monitor For 12V Lead Acid Battery Diagram