ELECTRA 101
Wednesday, September 23, 2015
Measuring Instruments in the Panelboard
1. Frequency Meter
Ø Measures on how many times an event occur. This frequency meter is usually refrred to as counter. Frequency meter is connected in series with the generators. A problem also with the use of an frequency meter is the need for the meter to be inserted into the circuit and become part of it.
Warning: Mistakenly placing it in parallel with a circuit will blow the fuse, possibly damaging the meter and causing injury. In AC circuits, a current transformer converts the magnetic field around a conductor into a small AC current.
2. kVAR meter
As its name implies, kVAR meter measures or present the amount of reactive power present in a circuit. As we all know, KW and KVAR are confusing.
It seems that usually, one thinks that if KVAR's in a system is equal to zero, then there is no power flowing. (maling mali po). This person fails to understand that real power and apparent power are not the same for a system operating with a no unity power factor. This apparent power is simply circulating power due to the phase shift between the source and the loads. This additional power that appears to be flowing requires the equipment to be rated higher than that for a system operating at unity.
Obviously these circulating currents are really producing no useful work. It is the job of the EE or the power plant operator to correct the load reactance as close as possible to unity to increase efficiency and reduce operational costs. Thus, kVAR meter is very much helpful in the power plant.
3. Kilowatt Meter
Ø The kilowatt-hour meter is designed to reliably, and accurately measure the electrical energy (kWh) used in your home or place of business.
Ø When you look at the face of a kilowatt-hour meter, across the middle you will see a metal horizontal disc that turns when energy is being used. This disc is designed to turn like a motor wheel when energy passes through the meter, and it is calibrated so that one rotation of the disc corresponds to a specific number of kilowatt-hours. This means that depending on the meter make or type, one meter may spin twice as fast as another to register the same kilowatt-hours.
Ø The kilowatt meter and kilovolt-ampere meter measure the power (demand) delivered to the facility being metered averaged over a short duration of time. These facilities are larger users of power than residential or small commercial energy use
4. Synchroscope
Ø A synchroscope indicates when two AC generators are in the correct phase relation forconnecting in parallel and shows whether the incoming generator is running faster or slower than the on-line generator. The synchroscope consists of a two-phase stator. The two stator windings are at right angles to one another, and by means of a phase-splitting network, the current in one phase leads the current of the other phase by 90°, thereby generating a rotating magnetic field.
Ø The stator windings are connected to the incoming generator, and a polarizing coil is connected to the running generator. The rotating element is unrestrained and is free to rotate through 360°. It consists of two iron vanes mounted in opposite directions on a shaft, one at the top and one at the bottom, and magnetized by the polarizing coil.
Ø If the frequencies of the incoming and running generators are different, the synchroscope willrotate at a speed corresponding to the difference. It is designed so that if incoming frequency is higher than running frequency, it will rotate in the clockwise direction; if incoming frequency is less than running frequency, it will rotate in the counterclockwise direction. When the synchroscope indicates 0o phase difference, the pointer is at the "12 o’clock" position and the two AC generators are in phase.
Automatic transfer Switch, time delay???
EMERGENCY!
Dalawang supply sa ATS, isa galing sa utility company, isa galing sa generator para sa emergency power supply.
In case of any undervoltage, overvoltage, loss of phase, or total power failure, ang generator ay gagana after a PRESET TIME DELAY.
Then once na nastabilize ang generator voltage, that's the only time na ang UTILITY ACB ay mag-oopen o madidisconnect, at ang GENERATOR ACB ay magcloclose.
NORMAL...

However, in this case, hindi agad-agad magdidisconnect ang generator.
Magkakasabay pa din sila.. parehong aandar ang dalawang ACB and after a preset time delay (after magcool down ang generator), that's the only time that the GENERATOR ACB will be OPENED and disconnected again.
Mga Tao sa Likod ng ating Electrical Convenience Ngayon
- Ang pinakaunang electrical engineer na nabuhay noong 17 th century ay si WILLIAM GILBERT, isang scientist at natural philosoper. Sabi nga , siya ang father ng electricity at magnetism.
- William concluded that the Earth was itself magnetic and that this was the reasoncompasses point north (previously, some believed that it was the pole star (Polaris) or a large magnetic island on the north pole that attracted the compass). He was the first to argue, correctly, that the centre of the Earth was iron, and he considered an important and related property of magnets was that they can be cut, each forming a new magnet with north and south poles.
- In his book, he also studied static electricity using amber; amber is called elektron in Greek, so Gilbert decided to call its effect the electric force. Sya ang gumawa ng unang electroscope, gamit ang isang karayom.
- Ang pinakaunang tao naman na gumamit ng word na ELECTRICITY naman ay si Sir Thomas Browne, isang manunulat, Ang salita ay galing sa LATIN word na electricus, meaning "like amber".
- Sinundan si William Gilbert ni Alesandro Volta, isang physicist, na syang nakagawa ng BATTERY o ng unang electric cell. Sya ang nakadiskubre sa electric capaitance (C), sa charge (Q) at sa electric potential (V). ( Q = CV)
- Di rin pwedeng mawala sa listahan si ginawa ni Benjamin Franklin sa kanyang researches. Sya lang ang bukod tanging nagpalipad ng saranggola habang umuuln ng malakas at nagpatunay na ang kidlat ay isang klase ng kuryente. Dun din pumasok sa kanyang mga pagsasaliksik ang teorya sa grounding at marami pang iba.
- Pagkatapos sa kanya ay si George Ohm, isang German physicist at guro, na sya namang nagexplain ng pagkakaiba ng electric current at potential difference sa isang conductor na nagsimula ng electrical circuit analysis. Sikat ang kanyang OHMS LAW V = IR, at mula sa kanyang mga nagawang principle, ay ang applications na ng electric current.
- Andyan din si Michael Faraday, ang nag-imbento ng electric motor. Sa kanya nagsimula ang electromagnetic induction. Isang chemist at physicist, pinaghalong nya ang dalawang science at nabuo ang electrochermistry.
- Si Nikola Tesla naman kung saan pinangalan ang unit ng electromagnetic flux, ang "tesla", hehe. Sya naman ay nagconcentrate sa electromechanical engineering. Sa AC machines at sa polypahse, panalong panalo tayo sa kanyang mga ibinahaging kaalaman.
- Si Thomas Edison naman ang pinakapaborito ko. Siya lang naman ang nakaimbento ng motion-picture camera at ang nagdala ng liwanag sa ating kabahayan sa kanyang naimbentong "ELECTRIC BULB". At an early age, Thomas Edison developed a hearing impairment, pero di ito naging hadlang para di sya magtagumpay. Napunta sila sa Michigan ng kanyang pamilya at dun ay nagtinda sya ng mga candy, newspaper at mga gulay. At dahil sa likas na madiskarte, ang maliit na businessman ay swerteng napasok sa GENERAL ELECTRIC, isang malaking company. Quotable quote: We will make electricity so cheap that only the rich will burn candles." =)
Inside The Big Box
Parang sa larong CHESS, ang bawat bahagi ng magnetic control ay may kanya-kanyang operasyon. Bawat isa ay nagtutulungan para madepensahan ang kanilang hari, TAYONG MGA TAO.
MCC, 440 V, Free-standing in Nema I enclosure and to contain the ff:
Main: 700 AT, 3P, MCCB
Metering:
1 - Digital multimeter
5 - Cylindrical fuse
3 - current transformer
Ang main circuit breaker ay mahahalintulad sa isang reyna. Sya ang pinakamalaking proteksyon sa control circuit. Sya ang humaharang sa mga aksidenteng pwedeng mangyari.
Ang Digital Multimeter naman ang BISHOP. Sya ang kanang kamay ng CIRCUIT BREAKER.
Katulad ng bishop, ito'y nagsisilbing tagamonitor sa daloy ng kuryente. Iba't ibang klase ng importanteng impormasyon ang pwedeng makita dito kasama na ang boltahe, amperahe, power, hertz at iba pa)
Ang mga fuse naman at current transformer ang mga pawn. Bilang auxiliary devices, sila ay tulong para sa malaking equipment gaya ng metro.
to be continued...
MCC, 440 V, Free-standing in Nema I enclosure and to contain the ff:
Main: 700 AT, 3P, MCCB
Metering:
1 - Digital multimeter
5 - Cylindrical fuse
3 - current transformer
Ang main circuit breaker ay mahahalintulad sa isang reyna. Sya ang pinakamalaking proteksyon sa control circuit. Sya ang humaharang sa mga aksidenteng pwedeng mangyari.
Ang Digital Multimeter naman ang BISHOP. Sya ang kanang kamay ng CIRCUIT BREAKER.
Katulad ng bishop, ito'y nagsisilbing tagamonitor sa daloy ng kuryente. Iba't ibang klase ng importanteng impormasyon ang pwedeng makita dito kasama na ang boltahe, amperahe, power, hertz at iba pa)
Ang mga fuse naman at current transformer ang mga pawn. Bilang auxiliary devices, sila ay tulong para sa malaking equipment gaya ng metro.
to be continued...
Trouble sa Bahay? Maghanap ba?
Karaniwang electrical problems: faulty wiring, maraming appliances sa isang circuit, sirang switch at receptacles, defective electrical cords, etc. Ang short circuit ay nagyayari lamang pag ang hot wire ay natama sa neutral o sa ground wire. Ang extrang current na dumadaan sa conductors ay magpapatrip sa breaker.
Note: I-off ang breaker at RESET. Heto ang limang kondisyon na dapat tingnan sa pagtrtroubleshoot ng electrical fault.
1) PAG NAGTRIP KAAGAD ang breaker ==> ang switch o receptacle ay shorted
2) PAG HINDI NAGTRIP ANG BREAKER AGAD ==> iturn off lahat ng appliances o load, o switches at isa isang pagananahin.
3)PAG NAGTURN ON NG ISANG SWITCH AT NAGTRIP ANG BREAKER ==> merong short circuit sa fixture o receptacle na kinokontrol ng switch
4) PAG HINDI GUMANA ANG CIRCUIT PAGKATAPOS IPLUG ANG APPLIANCE ==> ang problema ay nasa electrical cord ng appliance
5) PAG HINDI GUMANA ANG CIRCUIT PAGKATAPOS I-TURN ON ANG APPLIANCE ==> ang appliance mismo ang depektibo
Note: I-off ang breaker at RESET. Heto ang limang kondisyon na dapat tingnan sa pagtrtroubleshoot ng electrical fault.
1) PAG NAGTRIP KAAGAD ang breaker ==> ang switch o receptacle ay shorted
2) PAG HINDI NAGTRIP ANG BREAKER AGAD ==> iturn off lahat ng appliances o load, o switches at isa isang pagananahin.
3)PAG NAGTURN ON NG ISANG SWITCH AT NAGTRIP ANG BREAKER ==> merong short circuit sa fixture o receptacle na kinokontrol ng switch
4) PAG HINDI GUMANA ANG CIRCUIT PAGKATAPOS IPLUG ANG APPLIANCE ==> ang problema ay nasa electrical cord ng appliance
5) PAG HINDI GUMANA ANG CIRCUIT PAGKATAPOS I-TURN ON ANG APPLIANCE ==> ang appliance mismo ang depektibo
Welcome to Wherever You Are (Translation) by Bon Jovi
Jan 16, 2013
I have never liked the type of music bon jovi plays when I was a child.. but yesterday, Jan. 15, 2013, I happened to listen one of his songs and found it very real and meaningful. :)
Maybe we're different, but we're still the same
Siguro nga magkaiba pero pareho pa din tayo
We all got the blood of Eden, running through our veins
Nananalaytay sa ugat natin ang dugo ng Eden
I know sometimes it's hard for you to see
Lam kong mahirap para sa yo mapagtanto
You come between just who you are and who you wanna be
Ika’y nalilito sa kung sino ka at ano ang gusto mo
If you feel alone, and lost and need a friend
Kung pakiramdam mo’y ikaw ay nag-iisa at kailangan ng kasama
Remember every new beginning, is some beginning's end
Tandaan lang na ang lahat ng pagsisimula ay pagtatapos ng isa..
Welcome to wherever you are
Tuloy ka lang sa kung saan ka ngayon
This is your life, you made it this far
Buhay mo yan, layo na din ng iyong napuntahan
Welcome, you gotta believe
Tuloy ka, manalig ka lang
That right here right now, you're exactly where you're supposed to be
Karapatdapat namang andito ka
Welcome, to wherever you are
Tuloy lang, tuloy ka.
When everybody's in, and you're left out
Kung ikaw ma’y minsan napag-iiwanan
And you feel your drowning, in a shadow of a doubt
At pakiramdam mo’y nalulunod ka sa walang kasiguraduhan
Everyones a miracle in their own way
Lahat tayo’y may mahika sa kanya-kanyang paraan
Just listen to yourself, not what other people say
Wag makinig sa iba, sarili’y paniwalaan.
When it seems you're lost, alone and feeling down
Kung ikaw man ay nawawala, nalulungkot at nag-iisa
Remember everybody's different
Tandaan mong lahat tayo’y iba-iba
Just take a look around
Tumingin ka lang, kaibigan
Be who you want to, be who you are
Magpakatotoo ka, at sa gusto mong maging
Everyones a hero, everyones a star
Lahat tayo’y bayani, lahat tayo’y bituin
When you wanna give up, and your hearts about to break
At kapag gusto mo nang sumuko at nasaktan ang iyong puso
Remember that you're perfect, God makes no mistakes
Ang Dyos na gumawa ay laging tama.. tayo’y perpekto.
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