Bro statix, ah gets, masisira eventually... my problem is nalalakasan pa rin ako sa 220v kahit 1st setting... 1 2 3 lang eh sana may 0.5 or 0.25 power... May electric fan ba na ganun kahina na parang 220v fan na kinabit sa 110v? Or is there a safer way para magawang less than 1 yung lakas nya?
Also, di ko po mahanap yung reply button? kaya hindi kita ma-quote sa reply hehe...
Forum Topic
Ask Sir Tony - an Electronics/Electrical Q & A thread
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Walang reply button. Copy+paste lang ng text tapos gamitin yung Quote na tag.
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my problem is nalalakasan pa rin ako sa 220v kahit 1st setting... 1 2 3 lang eh sana may 0.5 or 0.25 power... May electric fan ba na ganun kahina na parang 220v fan na kinabit sa 110v? Or is there a safer way para magawang less than 1 yung lakas nya?
your bet would be a DC fan. marami nyan sa online shops. -
Bro statix, ah gets, masisira eventually... my problem is nalalakasan pa rin ako sa 220v kahit 1st setting... 1 2 3 lang eh sana may 0.5 or 0.25 power... May electric fan ba na ganun kahina na parang 220v fan na kinabit sa 110v? Or is there a safer way para magawang less than 1 yung lakas nya?
Yung electric fan ko sa room Asahi na industrial fan. Masyado malakas kahit sa slowest setting, especially kapag Jan-Feb kung saan malamig ang weather. Ang ginawa ko dinikit ko sa variable autotransformer or "Variac", which is a special transformer na pwede mo i-vary ang voltage from slightly above 0 volts up to 267 volts. Usually pinapatakbo ko between 140-180 volts ang fan at "2" na speed setting. Ang kagandahan ng variac pwede mo patakbuhin ang speed ng fan sa exact na gusto mo, unlike yung stepped na fan control at 1, 2, 3, etc. Ang problem mahal kasi ang variac, halos 1.5K ata yung 500W variac ko. Electrical hobbyist kasi ako kaya binili ko, pwede ko rin kasi gamitin sa ibang projects.
Regarding 110 volts sa electric fan, actually pwede. Simple device lang naman kasi ang fan (induction motor), hindi high-tech na pwedeng masira sa low voltage. In fact ang parents ko nagpapatakbo ng ancient electric fan (20 years old na siguro) sa room nila using 110 volts kasi nalalakasan sila pag 220 volts. Siguro at least 10 years na nilang ginagawa yan, which is simple proof na kaya ng electric fan ang lower voltage. Eh kung talagang masisira ang fan sa 110 volts siguro nangyari na yan sa loob ng sampung taon diba? Basta ang important umikot ang fan ng reasonable speed sa 110 volts. Kung hindi, yan ang time na pwede siya masira. ;-)
-- edited by HwiNoree on Aug 07 2023, 09:41 AM -
Dati may napanood ako sa youtube, fixing electric fan tutorial - pinapalitan ang capacitor para lumakas ... pwede kaya palitan to lower naman para humina?
Ganyan din kc ang hanabishi desk fan - lowest pero ang lakas pa din. -
Tingin ko pwede yan pero AFAIK ang pinaguusapan diyan pag-alter ng capacitor values ng capacitor-based fan control (article here: <click here for link>, makikita rin sa video na to: <click here for link>) at hindi yung run capacitor na nakadikit sa starting winding ng fan (article here: <click here for link>). Medyo complicated yan, ang simplest way para maging precise ang speed control variac talaga kaso mahal lang. Ang maganda kasi sa variac yung sinusoidal waveform ng AC ay preserved, unlike sa triac.
Nasubukan ko na gumamit ng triac (commonly used as dimmer) for speed control pero grabe ang hum sa most fans (medyo complicated ang explanation, kung interested just look kung paano gumagana ang triac at yung resulting waveform ng kuryente). Meron akong nakitang interesting circuit diagram for speed control using combination ng triac at diac para ma-minimize ang fan hum na main problem ng pure triac. Link at video here: <click here for link>. Try ko assemble yung circuit one time kasi mura lang naman ang parts, meron rin kasi akong isa pang AC fan na gusto i-control ang speed.
-- edited by HwiNoree on Aug 07 2023, 07:35 PM -
Yung electric fan ko sa room Asahi na industrial fan. Masyado malakas kahit sa slowest setting, especially kapag Jan-Feb kung saan malamig ang weather. Ang ginawa ko dinikit ko sa variable autotransformer or "Variac", which is a special transformer na pwede mo i-vary ang voltage from slightly above 0 volts up to 267 volts. Usually pinapatakbo ko between 140-180 volts ang fan at "2" na speed setting. Ang kagandahan ng variac pwede mo patakbuhin ang speed ng fan sa exact na gusto mo, unlike yung stepped na fan control at 1, 2, 3, etc. Ang problem mahal kasi ang variac, halos 1.5K ata yung 500W variac ko. Electrical hobbyist kasi ako kaya binili ko, pwede ko rin kasi gamitin sa ibang projects.
Regarding 110 volts sa electric fan, actually pwede. Simple device lang naman kasi ang fan (induction motor), hindi high-tech na pwedeng masira sa low voltage. In fact ang parents ko nagpapatakbo ng ancient electric fan (20 years old na siguro) sa room nila using 110 volts kasi nalalakasan sila pag 220 volts. Siguro at least 10 years na nilang ginagawa yan, which is simple proof na kaya ng electric fan ang lower voltage. Eh kung talagang masisira ang fan sa 110 volts siguro nangyari na yan sa loob ng sampung taon diba? Basta ang important umikot ang fan ng reasonable speed sa 110 volts. Kung hindi, yan ang time na pwede siya masira. ;-)
i see,,, that's good to know then ;) -
statix
tama si sir statix. stepless variable speed ang control ng dc fan na gumagamit ng pwm speed controller. mula sa sobrang hina hanggang full speed. madali lang naman mag-diy. pwede motor lang (755) at speed controller ang bilhin mo. o kaya kung may budget, yung brushless motor na. kumpleto na, isalpak mo lang sa lumang AC fan. yung mga nabibiling dc fan, diode lang ang gamit sa speed control (1,2,3), pwede mo palitan ng pwm speed controller para pwede mo imaual adjust ang speed ng fan. ang advantage pa ng dc fan, matipid sa kuryente, sa speed na ginagamit ko, 5 watts lang ang kunsomo. sa pinakamalakas, aabot lang ng 18 watts.
your bet would be dc fan -
^Sa ayaw mag DIY pwede bumili ng commercially sold na DC motor electric fans. AC parin ang power source pero may inverter para gawin DC, so that yung motor itself ay DC motor. Example niyan would be:
Panasonic F-409SS DC Inverter Stand Electric Fan
<click here for link>
Quoting sa specs: "ROTARY DIAL KNOB: Smooth, continuous control dial to generate speed"
A bit on the expensive side at PhP 3,899 (from Shopee Mall, official store ng Panasonic) pero on the long term makakatipid dahil sa lower power consumption. Wala lang akong idea sa specific kind ng motor sa loob ng fan pero sana brushless DC (BLDC), tulad ng nakikita sa hard drives para walang wear-and-tear sa commutator na ginagamit sa brushed DC motor.
Pag existing AC fan wala talang magandang method para gumawa ng continuous speed control maliban sa autotransformer (variac). Pwede rin tinatawag na VFD pero expensive and complicated and usually ginagamit yan sa 3-phase induction motors sa industrial setting.
-- edited by HwiNoree on Aug 17 2023, 08:20 AM -
Nasira yung touchpad ng microwave namin. May marerefer ba kayo kung saan pwede maka order ng replacement part?
Tried to search for the model number: je12560spss microwave touchpad pero wala ako makita sa search results eh. -
^ Tawag ka sa CYA Industries Inc. Sila may nagsu-suporta ng GE appliances dito.
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Thanks to everyone bro statix & HwiNoree for the suggestions, I looked sa shopee for dc fans and dc controllers meron palang ganun klase na fan, also dc motors meron pala for sale, eto na gagawin ko from now on. :)
HwiNoree me too sobrang tagal na since high school ako (late 90's) ko pa gamit yung 110v transformer, so far ok pa naman yung fan hehe, pero baka kasi National yung brand kaya matibay hehe ;-)
Yung variac makakasira eventually rin ba yun ng fan? Is a variac just a transformer with stepless control? Or a variac will not break an electric fan vs. a transformer?
To clarify, lessening the voltage whether using transformer or variac also lessens power consumption? For less meralco bill hehe
BlackMoon bro yung 755 is the model of the motor, right? Nakita ko sa shopee RS-755 I guess that's it? Thanks sa suggestion, ok 'to sa mga lumang cheap fan brand na ayaw na umikot after a while (even if they were never plugged sa 110v). Ipakabit ko dito sa electronics shop na malapit :) Pansin ko Asahi Hanabishi 3D yung mga ganun lang talaga tumatagal... and of course National tumagal rin. Pero yung other cheap brands sa mga pinapa-rental units namin after 5yrs kailangan na WD-40 once in a while...
-- edited by jakobspiral on Aug 19 2023, 11:58 PM
-- edited by jakobspiral on Aug 20 2023, 12:03 AM
By the way I don't know why pero 12 hours late yung "time posted" pag edit, kasi I edited this comment twice on lunchtime of Aug 20 pero ang lumabas is Aug 19 11:58 PM (when yung totoo is dapat Aug 20 11:58 AM) hehehe
-- edited by jakobspiral on Aug 20 2023, 12:16 AM -
hi masters, mmm mejo ot, pero last log in ni sir Tony is year 2020?
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Yung variac makakasira eventually rin ba yun ng fan? Is a variac just a transformer with stepless control? Or a variac will not break an electric fan vs. a transformer?
Hindi, not unless pinatakbo mo sa napakbabang voltage at tumigil ang fan ng hindi mo namamalayan, kunwari habang tulog ka. Meron akong electric fan na nasira that way, kasi medyo may problem na sa bushing at nagstu-stuck paminsan ang shaft. Pinatakbo ko ng medyo mabagal at along the way habang ginagamit na stuck yung shaft at hindi na nagrotate ang fan. By the time na napansin ko maiinit na yung motor at ayaw na tumakbo, baka may nasira na sa windings mismo. So patakbuhin mo lang ng reasonable speed (at make sure walang problem sa bushing and/or shaft ang fan mo) at dapat walang problem using lower voltages.
Going into more detail, remember na ang usual ceiling fan control na may fixed fans speeds (1,2,3,4 etc.) ay gumagamit ng capacitors to change the voltage, i.e. voltage divider so that pag nasa low na setting mababa ang voltage na pumupunta sa fan at pag mas mabilis mas mataas ang voltage. In that regard, ang variac functions identically in that kaya niya magbigay ng mataas or mababang voltage. Ang difference lang is that pwede i-vary ng variac and voltage over a range. Sa desk fans hindi common ang capacitor na voltage/speed control, ang capacitor doon ay para sa starter winding. Eto ay tinatawag na permanent split capacitor (PSC) design, at ang speed control diyan ay achieved simply by multiple taps sa windings. Pag gusto mabilis ang fan mas malaking portion ng windings ang active = greater magnetic field = more rotation speed.
For greater clarity, panoorin mo yung video na to:
Speed Control for Shaded Pole and PSC motors; How they work!
Note na may portion ng video diyan kung saan ginagamit niya yung variac to change yung fan speed.
Is a variac just a transformer with stepless control?
Essentially, yes. Ang "variac", better referred to as an autotransformer (since "Variac" ay brand name) ay special na transformer na single lang ang winding. Toroidal transfomers ang usual design, pretty much identical sa transformers na nasa loob ng servo-based AVRs. Meron siyang rotating tap (carbon brush) for the secondary side, so that pag inikot mo yun tap pwede mo baguhin yung output over a wide range. In contrast, ang usual transformers ay may two windings at fixed lang ang outputs, e.g. 110 volts lang. The other important difference is that walang electrical isolation sa autotransformer, unlike sa usual transformers na coupled lang ang primary and secondary windings through magnetic flux.
To clarify, lessening the voltage whether using transformer or variac also lessens power consumption? For less meralco bill hehe
I think so, pero best kung meron kang wattmeter para masukat mismo yung konsumo ng appliance:
-- edited by HwiNoree on Aug 21 2023, 02:04 AM -
@Jakobspiral
maliban sa dc motor at PWM speed controller, kailangan mo din ng dc fenale jac na 5.5x 2.1mm para sa saksakan ng adapter at 12 volts dc adapter na at least 3 amps. -
mga sir ano kaya value nito wala kasi ako makita online exact type ng resistor
ang na search ko 50.8ohms, pwede kaya mga 51ohms na resistor?
thanks
-- edited by sitcoms on Sep 02 2023, 11:50 PM
-- edited by sitcoms on Sep 02 2023, 11:57 PM -
I don't think 50.8 ohm resistor yan. Based sa pictures mo, from left to right eto ang colors:
Green (1) - Black (2) - Silver (3) - Gold (4) - Black (5)
By "common sense" five bands means 5-band resistor right? Kaso kung sinubukan mo gumamit ng resistor calculator, walang option para piliin ang silver sa 3rd band. That's because hindi pwede gold or silver sa 3rd significant digit ng 5-band resistor (pwede lang ay black, brown, red, orange, yellow, green, blue, violet, gray at white, corresponding to 0-9 respectively). Ang answer diyan ay hindi kasi 5-band resistor yan pero 4-band na may temperature coefficient (ppm/K).
Quoting from https://www.allaboutcircuits.com/tools/resistor-color-code-calculator/:
5 Band Resistor With the 4th Band of Gold or Silver
All 5 band resistors with the 4th band of silver or gold form an exception and are utilized on specific or older resistors. The first two bands represent the significant digits, the 3rd band is a multiplication factor, the 4th band is for tolerance, and the 5th band is for the temperature coefficient (ppm/K).
Ang 4th band ng resistor mo ay gold, as mentioned sa quote above.
So band 1 ay green = 5, band 2 ay black = 0, band 3 ay silver = divided by 100, fourth band ay gold = 5% tolerance
50 / 100 = 0.50 ohm 5% resistor
5th band na black is temperature coefficient na 250 ppm/K:
More about temperature coefficient ng resistors here:
Temperature Coefficient of Resistance
<click here for link>
P.S.: Mukang pumutok ang electrolytic cap na 8.2 microfarad sa first picture, may missing piece na aluminum sa top at nag-buckle outward rin ang taas with brown traces na mukang dried electrolyte
-- edited by HwiNoree on Sep 03 2023, 07:11 AM -
Thank you sir will look for 0.5 ohms resistor
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HwiNoree, thanks so much for the info bro! What variac brand do you use? I'll buy a variac based on your recommendation, kasi gusto ko gamitin sa wall exhaust fan sa bahay namin, wala syang control at all so it would be nice na magkaron ng control for exhaust fan for once :)
BlackMoon, ini-screenshot ko yung instructions and hingi ako ng tulong sa electrician dito kasi bro di ako marunong mag DIY ng electronics hehe, maraming salamat boss sa tulong! may mga sira kaming fans dito sa bahay, gawin ko yung DC fan suggestions mo :) -
Sa totoo lang masyado mahal ang variac just to control ang fan. Ang Hossoni na variac na gamit ko (500 watts) 1.8K sa Shopee, although out of stock currently sa mga sellers ang 500 watts. Sa case ko, since pwede ko siya gamitin for other purposes (as someone na mahilig mag-tinker ng electrical stuff), worth it naman. Sa case mo na single purpose lang, I don't know kung worth it. Ang problem lang walang ibang decent at cheap way para magkaroon ng precise control sa speed ng AC fans na gumagamit ng induction motors. Nasubukan ko na gumamit ng triac-based na motor controller, very cheap pero useless dahil sobrang "dirty" ng output (choppy ang waveform ng voltage) kaya grabe mag-hum ang fan, parang masisira. Useful lang siya sa stuff na hindi sensitive sa choppy na output tulad ng incandescent light bulb (pwede gamiting dimmer).
-- edited by HwiNoree on Sep 28 2023, 07:28 AM -
HwiNoree thanks for the reply bro! :) Naisip ko pwede ko dalhin yung variac to whichever room I'm currently in the house (lalo na if magaan lang naman sya), kasi paiba-iba talaga temperature eh hehe, like right now naulan pero kanina maaraw :-D If lifetime naman gamitin (or at least a decade) then ok na rin :) It's harder to setup each fan to be DC with a controller, when maraming fan na AC dito sa bahay...
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I see, medyo mabigat yung 500-watt variac pero hindi naman sobrang bigat. Pwede mo i-secure sa wooden base at lagyan ng handles para mas madaling bitbitin. BTW, kailangan siya i-setup ng konti, dahil yung mga nabibiling variac walang input na plug at output na socket. Minimum is cord na may plug sa dulo papuntang input terminals, then cord na terminated into a socket na naka-screw sa output terminals.
Kung hindi ka naman nagmamadali hintayin mo mag-restock ang sellers ng 500 watts na variac. Yung 1000-watt and higher variacs ang currently available sa Shopee at overkill para sa fans, especially considering na parang 3K ang presyo ng 1 KW variac.
-- edited by HwiNoree on Sep 28 2023, 07:31 AM - Post deleted #12457061