Pad-mounted green transformer box wɔ gyaade buzzing, leaking mineral oil, anaasɛ ɛpae: anammɔn tumi ne 7,200 V primary arc clearance¶

Sɛ wote asɛm bi a ano yɛ den, a ɛnyɛ nea ɛkɔ so daa 120-hertz dade a ɛyɛ dede anaasɛ atuo a ɛte sɛ atuo a efi dade ahinanan a ɛyɛ ahabammono adaka a wɔde di dwuma no mu (pad-mounted distribution transformer) sɛ wobɛtra w’anim gyaade, wobɛte anyinam ahoɔden a wɔahyew a ɛyɛ nwini anaasɛ ngo a ɛwɔ sulfur hua, anaasɛ wubehu sare bruu a ahyew ne ngo tuntum a ɛretu afi kabinet no ase no yɛ ntɛmpɛ a ɛde ahoɔden kɛse a ɛde wo nkwa to asiane mu. Wɔ atrae nketewa a enni nnua a wɔde di dwuma wɔ soro no mu no, anyinam ahoɔden adwumayɛbea ahorow no fa asase ase nhama titiriw a wɔde ma a ɛde ** .7,200 volts to 19,920 volts (7.2 kV to 19.9 kV phase-to-ground, anaasɛ ɛkɔ soro kosi 34,500 volts phase-to-phase)** tẽẽ kɔ saa dade nkuku a ɛyɛ ahabammono no ase kɔ anammɔn voltage ase kɔ 120/240-volt ofie tumi. Ɛwom sɛ dade a ɛyɛ ahabammono akyi no te sɛ dade adaka a ɛnyɛ den de, nanso akyi fã no yɛ dade a wɔde nhyɛso ahyɛ mu ma 150 to 500 liters (40 to 130 gallons).

Sɛ emu winding insulation di nkogu a, nnua ntini anaa asase a ɛtwetwe no paapae asase ase bushing bi mu, anaasɛ concentric neutral ground wire no sɛe, a 7,200-volt arc a ɛwɔ mu no ma mineral oil a atwa ho ahyia no yɛ nwini ma ɛbɛyɛ hydrogen (H2), acetylene a wɔde yɛ nneɛma ( .C2H2), methane ( .CH4), ne ethylene gas wɔ milisekɔn mu. Sɛ bayonet fuse anaa pressure-relief valve a ɛwɔ mu no ntumi nyi nhyɛso no nkɔ ntɛmntɛm sɛnea ɛsɛ a, dade tank no mu paapae anaasɛ ɛbɔ n’apon a wɔde hinge ayɛ no bue wɔ anifurae mu 19,000-degree-Celsius (35,000-degree-Fahrenheit) arc-flash fireball bere a ɛma asase a atwa ho ahyia ne dade kabinet shell ahoɔden wɔ ahoɔden a edi awu mu. Sɛ transformer a wɔde pad asisi so no renom wusiw, ɛreyɛ arc, ɛrehuruhuruw, ngo retu, anaasɛ ɛte a ne pon abue a, frɛ wo mpɔtam hɔ nɔma a wɔde ma ntɛmpɛ (911 wɔ United States ne Canada no, . 112 wɔ Europa Aman Nkabom no nyinaa mu, . 999 wɔ United Kingdom no; hwɛ nɔma ahorow a egye ntɛmpɛ) ne wo anyinam ahoɔden adwumayɛbea no 24/7 ntɛmpɛ dispatch desk ntɛm ara. Sɛ wopɛ anyinam ahoɔden ne nneɛma a wɔde di dwuma ho haw ahorow a ɛfa ho a, hwɛ pad-mounted green transformer box a ɛpae, ngo ogya, ne kabinet a wɔabue mu asiane, . ahoɔden a ɛyera wɔ dade mmɔnten so akanea, akwan ho tokuru a wɔde kata so, ne akraman a wɔnantew ahopopo so, na downed telecommunications fiber anaa coax cable vs. ahoɔden a ɛto so abien tumi a ɛtɔ wɔ kar kwan so nkyerɛkyerɛmu.

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Yɛ eyi mprempren¶

1. Fa ntɛm ara exclusion perimeter a anyɛ yiye koraa no 10 to 15 meters (35 to 50 feet) twa transformer adaka a ɛyɛ ahabammono no ho hyia, na trɛw mu kɔ 30 meters (100 feet) sɛ ɛregye sigaret, ɛreyɛ hwirew, anaasɛ ɛrehuruhuruw a. Mma nnkɔ transformer adaka a ɛrebɔ, sigaret, anaa ngo a ɛretu no nkyɛn da nkɔhwɛ mu, nka dade kabinet no da, na mma mmofra anaa afieboa mmɛn kɔnkrit pad no da. Sɛ wugyina mu dedaw a 10 meters (35 feet) a ɛfa transformer a ɛhyɛ aseɛ yɛ arcing, roaring, anaa flashing, ntu mmirika mfa anammɔn tenten: shuffle anaa hop backward keeping both feet tightly together so a 7,200-volt asase-mfomso voltage gradient (anamɔn tumi) ntumi nkɔ soro nan biako na ɛba fam foforo.
2. Fa akraman to hama ntiantiaa so wɔ akyirikyiri fi kabinet no ho na mma ɔkraman ntow nsu anaasɛ nhu transformer adaka a ɛyɛ ahabammono a ayɛ mmerɛw da. Akraman wɔ anan a enni insulated a ɛne sare a ɛyɛ nwini di nkitaho tẽẽ ne hwene a ɛyɛ nsu a ɛka dade ntwea so. Sɛ ɔkraman tow nsu gu transformer a ne fam ahama anaa ne nsateaa titiriw a ɛwɔ mu no asɛe no ase a ayɛ mmerɛw no so, anaasɛ ɔtow gu asase a ahoɔden wom so a, . 120 to 7,200 volts tu kwan fa nsu a ɛkɔ nsu mu no mu anaasɛ ɛfa ɔkraman no de no so 0.6-meter (2-foot) anim-kɔ-akyi paw span, na ɛma ventricular fibrillation ntɛm ara.
3. Fa binoculars anaa wo smartphone camera zoom fi 15+ meters (50+ feet) akyirikyiri na woakenkan Utility Stencil Number a ɛwɔ ahinasa 6 kosi 10 a ɛwɔ adaka no anim no. Transformer biara a wɔde pad a ɛyɛ ahabammono ahyɛ mu no wɔ stencil nɔma a ɛyɛ kɔkɔɔ, fitaa, anaa tuntum a wɔde kyerɛ sɛ wɔde stencil ayɛ (ne barcode tag ne a kVA sticker te sɛ 25, . 50, . 75, anaa 100) wɔ anim hood anaa afã panel no so. Sɛ wokenkan saa stencil nɔma pɔtee no kɔma utility dispatcher no a, ɛma wɔn outage management system no kwan (OMS) de ahu asase ase primary loop, upstream switching cabinet a ɛbɛn, ne afe a wɔyɛɛ no (PCB vs. Non-PCB mineral oil) ansa na line adwumayɛfo no aba.
4. Mmɔ mmɔden da sɛ wobɛpia ato transformer pon a wɔabue anaasɛ abɔ mu no mu, na fa nsuo anaa ofie ogya dum afiri petepete adaka no so da. Sɛ asase no ho asɛe, nneɛma a wɔsɛe no, anaa nhyɛsoɔ a ɛwɔ mu no ama dadeɛ hood a ɛyɛ ahabammono no ayɛ mmerɛw a, anyɛ yie koraa no, tena akyi 10 to 15 meters (35 to 50 feet) na ɛyɛ. Wɔ kabinet no mu no, rɔba a ɛwɔ ahoɔden a ɛkorɔn titiriw nsateaa (7,200 to 19,920 V) ne kɔbere a ɛda hɔ kwa a ɛto so abien busbars ( .120/240 V at 2,000+ amps of available fault current) tra ase sɛntimita fi ɔpon ano ano. Mfa turo mu hose anaa ofie a wɔde nsa yɛ nni dwuma da ABC extinguisher (a wɔahyɛ no agyirae ama mfiri a ɛwɔ dan mu nkutoo wɔ ase 1,000 volts).
5. Hwɛ wo fie sɛ "Open Neutral" voltage swings na dum wo Main Breaker sɛ kanea reyɛ flickerly anaasɛ ɛdannan anifurae hyerɛn. Sɛ asase ase transformer yɛ hyew dodo anaasɛ ne neutral connection hyew loose wɔ green cabinet no mu a, wo fie abien 120-volt nan bɛyɛ nea ɛnkari pɛ (sending 180 to 210 volts wɔ wo outlets fã mu bere a woreto fã a aka no akɔ 40 volts). Sɛ wo dan mu breaker panel no yɛ nwini, ɛyɛ nwunu, na ɛyɛ komm a, gyina nkyɛn na dannan Main Service Breaker no kɔ OFF sɛnea ɛbɛyɛ a surge strips ne appliance boards renhyew. (Sɛ wo dan mu panel no ankasa rebɔ denneennen, ɛrenom sigaret, anaasɛ ɛyɛ hyew a, nka panel no: fi fie hɔ ntɛm ara.)
6. Fa abusua no mufo ne afieboa bra dan mu, to mfɛnsere nyinaa mu, na to HVAC mframa a ɛkɔ mfinimfini no mu sɛ transformer no retu wusiw anaasɛ ngo a ɛretu a. Dielectric mineral oil a ɛhyew anaasɛ ɛyɛ hyew no ma dense polycyclic aromatic hydrocarbons (PAHs), aldehyde a ɛyɛ nwini, carbon monoxide, ne nsu a ɛyɛ fĩ; wɔ agyapade units a cross-contaminated ansa na 1979 EPA bara, hyew polychlorinated biphenyls ( .PCBs) ma awuduru dibenzofurans a wɔde chlorine ayɛ ( .PCDFs) ne dioxins.

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Gyinaesi dua: pad-mounted green transformer ntɛmpɛ triage¶

flowchart TD
    A["Abnormality wɔ mpɔtam hɔ green pad-mounted transformer adaka"] --> B{"Nsɛnkyerɛnne bɛn na wuhu fi akyirikyiri?"}
    B -->|"1. 120-Hz dede a ano yɛ den, arcing, wusiw, ogya, anaasɛ bulging/popped lid"| C["Tu fi baabi a ɛwɔ mita 15 kosi 30 (anammɔn 50 kosi 100) ntɛm ara"]
    B -->|"2. Nsu a srade wom a ɛsen kɔ kɔnkrit pad, sare a ahyew, anaa hua a aporɔw/ahyew so"| D["Tra akyi mita 10 kosi 15 (anammɔn 35 kosi 50); fa afieboa ne mmofra to mu"]
    B -->|"3. Kabinet pon no abue, padlock nni hɔ, anaasɛ penta-bolt a ɛwɔ nsɛntitiriw 5 no ayɛ mmerɛw"| E["MMFA wo nsa nka ɔpon anaa nto mu; awɛmfo perimeter fi 10+ mita akyirikyiri"]
    C --> F{"So wowɔ beae a asase so mfomso wɔ a ne tenten yɛ mita 10 (anammɔn 35) no mu dedaw?"}
    F -->|"Yiw"| G["Fa wo nan abien no nyinaa bom frafra anaa huruw kɔ akyi na woakwati Step Potential"]
    F -->|"Dabi"| H["Frɛ 911 Ogya a Wɔde Kɔma NE Electric Utility Emergency Line"]
    G --> H
    D --> H
    E --> H
    H --> I["Fa binoculars anaa telefon so zoom fi mita 15+ kenkan Stencil Number a ɛwɔ ahinasa 6 kosi 10"]
    I --> J{"So ofie akanea rehyerɛn denneennen, ɛhyerɛn kɛse, anaasɛ ɛyɛ huam te sɛ plastic a wɔahyew?"}
    J -->|"Yiw: Bue Neutral anaasɛ mfomso titiriw-kɔ-secondary"| K["Sɛ dan mu breaker box yɛ komm/onwini a, dan Main Breaker OFF; sɛ panel buzz a, tu fi fie"]
    J -->|"Dabi"| L["To mfɛnsere mu, dum HVAC intake, na twɛn Utility Hot-Stick Lineman"]
    K --> L
    L --> M["Demand Utility HazMat contractor no siesie ngo a ahwie agu nyinaa na ɔsɔ asase hwɛ sɛ PCBs wɔ hɔ anaa"]

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Anatomy of a green pad-mounted transformer: nea ɛwɔ kabinet no mu¶

Sɛ yɛte nea ɛte dade a wɔde ayɛ krataa a ɛwɔ transformer a ɛwɔ atrae a ɛwɔ phase biako a wɔde ahyɛ mu no akyi a, ɛkyerɛkyerɛ nea enti a utility linemen hyɛ 40 cal/cm2 arc-flash suits na fa ** di dwuma .2.4-meter (8-foot) fiberglass "shotgun" hot-stick** sɛnea ɛbɛyɛ a wobebue ɔpon no ara kwa:

+-----------------------------------------------------------------------------+
|        SINGLE-PHASE RESIDENTIAL PAD-MOUNTED TRANSFORMER (TOP/FRONT VIEW)    |
+-----------------------------------------------------------------------------+
|                                                                             |
|   +---------------------------------------------------------------------+   |
|   |                   REAR SEALED STEEL OIL TANK                        |   |
|   |  - Contains 150 to 500 L (40 to 130 gal) Dielectric Mineral Oil     |   |
|   |  - Houses High-Voltage Core & Copper/Aluminum Windings              |   |
|   |  - Internal Oil Temp under Peak Load: 65 C to 105 C (150 to 220 F)  |   |
|   |  - Dissolved Combustible Gases during Fault: H2, C2H2 (Acetylene)   |   |
|   +---------------------------------------------------------------------+   |
|   |              STEEL TANK WALL / BUSHING PARTITION PLATE              |   |
|   +----------------------------------+----------------------------------+   |
|   |  LEFT SIDE: HIGH-VOLTAGE (HV)    |  RIGHT SIDE: LOW-VOLTAGE (LV)    |   |
|   |  PRIMARY COMPARTMENT             |  SECONDARY COMPARTMENT           |   |
|   |  * Voltage: 7,200 V to 19,920 V  |  * Voltage: 120 / 240 Volts      |   |
|   |  * H1A & H1B Load-Break Elbows   |  * X1, X2, X3 Threaded Studs     |   |
|   |    (Loop-Feed In & Out to next   |    feeding 4 to 12 houses        |   |
|   |    transformers down the street) |  * Uninsulated bare metal spades |   |
|   |  * Bayonet Oil-Expulsion Fuse    |    with 2,000+ Amps fault current|   |
|   |  * Pressure Relief Valve (PRV)   |  * Concentric Neutral Ground Bar |   |
|   +----------------------------------+----------------------------------+   |
|              ^                       |                       ^              |
|     [Hinged Steel Hood]    [5-Point Penta-Head Bolt    [Utility Padlock]    |
|                             + Recessed Security Latch]                      |
+-----------------------------------------------------------------------------+

Nea enti a wɔde nhama ahyɛ transformers a wɔde ahyɛ pad so wɔ "Open-Loop Primary" (H1A ne H1B) .¶

Nea ɛnte sɛ overhead pole transformer a ɛbɔ waya biako wɔ soro no, ɛkame ayɛ sɛ transformer biara a ɛwɔ green pad-mounted a ɛwɔ atrae no yɛ underground loop-feed circuit fã: - A. A. 7,200-volt (anaasɛ 13,800 V / . 19,920 V) asase ase primary cable hyɛn adaka no ase benkum so fi ofipamfo a ɔwɔ soro no transformer (Bushing H1A), ɛma wo transformer no ahoɔden, na ɛfa elbow a ɛto so abien a ahoɔden kɛse wom so fi adi (Bushing H1B) de ma transformer 5 kosi 20 a edi hɔ no aduan wɔ abɔnten so. - Nea eyi kyerɛ wɔ ntɛmpɛ mu: Sɛ mpo wo transformer no mu Bayonet Expulsion Fuse bɔ na ɛbɔ anyinam ahoɔden kɔ wo fie ne w’afipamfo a wɔbɛn wo pɛɛ no mu mpo a, the 7,200-to-19,920-volt mfitiase loop nhama ( .H1A ne H1B) a ɛwɔ wo adaka a ɛyɛ ahabammono no ase mu no kɔ so tra hɔ ɔha biara mu nkyem 100 LIVE na ahoɔden kosi sɛ utility ɔhawfo bi behu upstream switching cabinet anaa riser pole no wɔ mmɔnten pii so na watwe fuses titiriw no. Mfa no da sɛ transformer adaka a ɛyɛ ahabammono "awu" esiane sɛ afie a ɛwɔ wo cul-de-sac no nyinaa ahwere anyinam ahoɔden nti.

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Diagnostic table: nea nnyigyei, hua, anaa sɛnkyerɛnne biara a wɔde aniwa hu kyerɛ¶

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Step Potential ne Touch Potential: nea enti a sare a atwa adaka a ɛyɛ ahabammono a ɛredi mfomso ho ahyia no betumi akum wo¶

Bere a primary conductor a ɛwɔ ahoɔden kɛse ( .7,200 V to 19,920 V) mfomso ahorow a ɛba dade transformer case no mu anaasɛ ɛkɔ fam, na asase ase kɔbere concentric neutral return wire no asɛe anaasɛ abubu, asase a atwa kɔnkrit pad no ho ahyia no yɛ adwuma sɛ anyinam ahoɔden a ɛko tia kɛse. Voltage fa asase no mu kɔ abɔnten wɔ concentric rings mu, na ɛkɔ fam fi volts mpempem pii wɔ concrete pad no so kodu zero volts wɔ 10 to 15 meters (35 to 50 feet): .

                    [ FAULTING GREEN TRANSFORMER BOX ]
                         (Cabinet & Pad at 7,200 V)
                                     |
          +--------------------------+--------------------------+
          |      Ring 1 (0.5 m / 2 ft):  ~5,500 Volts           |
          |   +---------------------------------------------+   |
          |   |    Ring 2 (1.5 m / 5 ft):  ~3,200 Volts     |   |
          |   |  +---------------------------------------+  |   |
          |   |  |   Ring 3 (3.0 m / 10 ft): ~1,400 Volts|  |   |
          |   |  |  +---------------------------------+  |  |   |
          |   |  |  |  Ring 4 (10 m / 35 ft): ~0 Volts|  |  |   |

1. Nea Enti a Nantew a Wɔyɛ no Daa Yɛ Owu (Step Potential):
2. Sɛ wo nante kɔ anaasɛ wotwe wo ho fi arcing anaa ground-faulted transformer fa normal 0.8-meter (2.5-foot) stride, ebia w’akyi nan no gyina dɔte so wɔ 1,400 volts bere a w’anim nan no tu anammɔn kɔ dɔte so wɔ 3,200 volts. Ɛno ** .1,800-volt nsonsonoe (Step Potential)** de anyinam ahoɔden a edi awu kɔ nan biako so tẽẽ, fa wo honam ani, na ɛkɔ fam wɔ nan foforo no so.
3. Nea Enti a Akraman a Wɔn Nan Anan Wu Ntɛm ara wɔ Voltage a ɛba fam kɛse mu: Ɔkraman bi a ɔnam sare a ɛyɛ nwini so wɔ baabi a ɛbɛn transformer a asɛe no spans 0.5 to 0.9 meters (1.5 to 3 feet) wɔ n’anim nan ne n’akyi nan ntam, ɛwɔ asen a ɛyɛ nsu a ɛko tia kakraa bi, na ɛwɔ ne koma no tẽẽ wɔ mprempren kwan a ɛkɔ soro a ɛda anim nan ne akyi nan ntam.
4. Sɛnea Wobɛguan Afiri Zone no Mu Dwoodwoo (The Shuffle / Two-Foot Hop):
5. Sɛ wote nka sɛ wo nan anaa wo nan ho reyɛ ayɛ wo yaw wɔ baabi a ɛbɛn utility box a ɛyɛ ahabammono, anaasɛ sɛ transformer no fi ase yɛ arcing, rebobom, anaa sigaret bere a wobɛn hɔ a, freeze, mia wo nan abien no nyinaa mu denneennen wɔ nkyɛnkyɛn, na shuffle kɔ akyi sɛnea ɛbɛyɛ a nan biako nantin rentwam wɔ ɔfoforo no nansoaa so da (ma wo nan abien no nyinaa nka bere nyinaa), anaasɛ hop backward with two feet landing bere koro mu kosi sɛ anyɛ yiye koraa no wobɛyɛ saa 15 meters (50 feet) akɔ akyirikyiri. Mfa wo nsa nka transformer cabinet anaa dade ban a ɛbɛn hɔ da bere a worebɔ wo ho akɔneaba (Touch Potential).

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Sɛnea wobɛbɔ Stencil Number ne Cabinet Type pɔtee ho amanneɛ akyerɛ Utility Dispatcher¶

Sɛ wofrɛ wo anyinam ahoɔden adwumayɛbea no 24/7 ntɛmpɛ nhama a, kenkan agyiraehyɛde ahorow a ɛwɔ kabinet no akyi no fi 15+ meters (50+ feet) kɔ akyirikyiri denam binoculars anaa wo fon no zoom lens a wode bedi dwuma so:

1. The 6-to-10-Digit Stencil / Pad Number: Hwehwɛ nɔma/nkyerɛwde a wɔde stencil ayɛ kɔkɔɔ, tuntum, anaa fitaa wɔ anim hood a ɛwɔ soro no so (te sɛ T-482910, . PAD 8492-A, anaa G-19402-3), a ɛyɛ map tẽẽ kɔ utility no GIS grid coordinates so.
2. Nea kVA Capacity Sticker: Mpɛn pii no, ɛyɛ nɔma a ɛyɛ ahinanan a ɛyɛ kɔkɔɔ ne tuntum anaa fitaa ne tuntum (25, . 37.5, . 50, . 75, . 100, anaa 167) a ɛkyerɛ kilovolt-ampere dodow a ɛwɔ mu.
3. "NON-PCB" Blue/Green Sticker (anaasɛ Nea Enni Mu):
4. Transformers a wɔyɛe wɔ akyi 1980 mpɛn pii no, wɔde ahinanan ketewaa bi blue, green, anaa fitaa kyerɛ "NON-PCB" decal wɔ anim anaa nkyɛn.
5. Sɛ transformer a akyɛ, a ɛyɛ ahabammono tuntum anaasɛ ɛyɛ rusted wɔ dabi NON-PCB decal (anaasɛ ɔte subdivision bi a ɛwɔ hɔ ansa na 1980 reba mu), ka kyerɛ Ogya Dwumadibea ne Utility Dispatcher sɛ: "Kabinet no nni Non-PCB sticker biara a wotumi hu na ngo retu; yɛsrɛ sɛ fa nea ɛbɛhwie agu no sɛ nsu a ebetumi ayɛ agyapade a PCB ayɛ mu fĩ."
6. Sɛnea Two-Stage Utility Security Lock no Yɛ Adwuma (Penta-Bolt + Padlock):
7. Ase ** .IEEE C57.12.28 / . NEMA enclosure standards**, wɔrentumi mfa kɔbere padlock nkutoo nkyekye transformer pon a wɔde pad a ɛyɛ ahabammono ahyɛ mu. Wɔ padlock hasp no ase no, recessed 5-sided (pentagonal) bolt a ahobammɔ kɛse wom ( .Penta-Bolt) a ɛhwehwɛ sɛ utility penta-socket wrench dannan ansa na padlock shackle no atumi akɔ mu. Sɛ padlock no sɛn hasp a wɔabue so anaasɛ ɔkwan bi da adi wɔ hood no ase ano a, na penta-bolt a ɛwɔ mu no ntra hɔ a, bɔ Unsecured Dead-Front Cabinet amanneɛ ntɛm ara.

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Dielectric Mineral Oil vs. Legacy PCB Spills: Ofiewuranom Ho Ahotew Mmara (40 CFR Part 761) .¶

Sɛ transformer a wɔde pad asisi so no tu anaasɛ ɛpaapae a, . 50 to 400 liters (13 to 105 gallons) a ngo a emu da hɔ, a ɛyɛ amber, anaa tuntum a ɛbɔ ho ban no betumi akɔhyɛ w’anim sare mu, akata wo kar kwan ne kar ahorow so, anaasɛ ahohoro akɔ baabi a ahum bɛbɔ.

• Mma w’ankasa wo nsa nka, popa, anaa hose down transformer ngo da: Sɛ wode turo mu hose anaa pressure washer petepete transformer ngo a ɛhwie gu so a, ɛma ngo no yɛ emulsify na ɛma petroleum hydrocarbons (ne agyapade biara Polychlorinated Biphenyls / PCBs, . CAS 1336-36-3) kɔ akyirikyiri wɔ sare so dɔte, ahum nsu a ɛkɔ nsu mu, ne asase ase nsu mu.
• Elektrik Dwumadibea no Soa Mmara ne Sikasɛm mu Asɛyɛde 100% wɔ Ahotew ho: Wɔ ɔman no nneɛma a atwa yɛn ho ahyia ho mmara ase (US EPA 40 CFR Part 761 Subpart G PCB Spill Cleanup Policy, Nsuo a Ɛho Tew Ho Mmara 40 CFR Part 112 SPCC Oil Spill Rules, ne ɔman/mantam/UK mmara), anyinam adwumayɛkuo no na ɛwɔ transformer a wɔde ahyɛ pad so no na ɛhwɛ nneɛma a ɛyɛ hu nyinaa nhwɛsoɔ, asase a wɔtutu, kɔnkrit pad a wɔbɛsesa, kar kwan/kar a wɔbɛpopa, ne sod a wɔbɛsan asiesie wɔ $0 ɛka a wɔbɔ ma ofie wura no.
• Nea ɛsɛ sɛ wɔhwehwɛ fi utility no nneɛma a atwa yɛn ho ahyia ho ɔhwɛfo hɔ ansa na wɔn adwumayɛfo no akɔ:
• Hwehwɛ sɛ utility no nneɛma a atwa yɛn ho ahyia ho hazmat contractor no tutu asase ne sod a ngo ayɛ so ma nyinaa nkɔ fam nkɔ asase a ɛho tew so (15 to 30 centimeters / . 6 to 12 inches akyi nkekae a wotumi hu no) na twe no kɔ wɔ DOT hazmat sanku a wɔatoto mu mu;
• Hwehwɛ laboratory Certificate of Analysis a wɔakyerɛw (anaasɛ adwumayɛbea din krataa a wɔagye atom) a ɛkyerɛ sɛ ebia nsu a ahwie agu no wɔ mu anaa < 1 ppm PCBs (Ngo a ɛnyɛ PCB mineral oil anaa abɔde mu ester nsu), . 50 to 499 ppm PCBs (PCB-Contaminated), anaasɛ >= 500 ppm PCBs (a ɛhwehwɛ sɛ EPA asase popa/core verification sampling wɔ ase 40 CFR § 761.125); na
• Sɛ ngo nsuo petepete wo kar anaa fie siding so a, fa Utility Property Damage & Environmental Decontamination Claim kɔ ntɛm ara ansa na woahohoro kar no.

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Mpɔtam hɔ ntɛmpɛ nɔma ne utility hazard protocols¶

• Amerika ne Canada:
• Ntɛmpɛ a Wɔde Kɔma: Dial 911 ntɛm ara ma sigaret, hyew, arcing, anaasɛ ɛpae green transformer box biara, anaasɛ sɛ cabinet pon bi abue a ɛda emu afã horow adi a.
• Electric Utility 24/7 Outage & Hazard Line: Frɛ ntɛmpɛ nɔma a ɛwɔ wo anyinam ahoɔden ka so no akyi pɛɛ 911 na fa Stencil Number a ɛyɛ 6-to-10-digit no ma nea ɔde kɔma no.
• Asase ase Hwehwɛ & Ngo a Ɛhwie Gu: Dial 811 ɔman no mu nyinaa wɔ U.S. nyinaa (call811.com) anaa ** .ClickBeforeYouDig.com** wɔ Canada ansa na wɔatutu fam. Bɔ transformer ngo a ɛho ntew ho amanneɛ kyerɛ Ɔman Mmuae Asoɛe (NRC) wɔ 1-800-424-8802 ne wo Ɔman DEP/ .EPA na ɛyɛ.
• Ahemman Nkabom:
• Emergency Dispatch & Ɔman Tumi a Wɔatwa / Asiane Nnɔmba: Dial 999 sɛ anyinam ahoɔden afiri a ɛyɛ ahabammono a ɛwɔ kwan ho (link box, feeder pillar, anaa package substation) rehyew anaasɛ ɛrepae a, na frɛ ** .105** (UK ɔman a wontua hwee Anyinam ahoɔden DNO Nnɔmba a Ɛho Hia Ntɛmntɛm wɔ England, Scotland, ne Wales nyinaa, anaa ** .03457 643 643** ma NIE Networks wɔ Northern Ireland) de bɔ amanneɛ sɛ kabinet a ɛreyɛ gyegyeegye, ɛretu, anaasɛ abue wɔ ** .HSE ESQCR 2002**.
• Europa Aman Nkabom Kuo:
• Ntɛmpɛ a Wɔde Kɔma: Dial 112 wɔ EU aman nyinaa mu sɛ wɔmfa transformer kiosk a ɛrehyew, ɛreyɛ dede, anaasɛ ɛbue wɔ kwan ho (poste de transformation HTA/BT wɔ France, Kompakttrafostation wɔ Germany, centro de transformación wɔ Spain) ho amanneɛ na wɔbɔ mpɔtam hɔfo amanneɛ DSO (Enedis / . e-distribuzione) na ɛyɛ. Anyɛ yiye koraa no, tra hɔ ** .15 meters (50 feet)** akyi.
• Australia ne New Zealand:
• Ntɛmpɛ a Wɔde Kɔma: Dial 000 wɔ Australia anaa ** .111** wɔ New Zealand sɛ ogya anaa ɔtopae a ɛretu wɔ Padmount Substation / Pillar Box a ɛyɛ ahabammono, na frɛ wo anyinam ahoɔden kyekyɛfo (Ausgrid 13 13 88, . Endeavour Energy 131 003, . Energex 13 19 62, . Western Power 13 13 51, anaa Vector wɔ NZ mu).
• Asia (Singapore, Japan, Hong Kong, ne India):
• Singapore: Frɛ 995 (SCDF) ne SP Kuw no Nnɔnhwerew 24 Electricity Service Center wɔ 1800-778-8888 wɔ mfomso ahorow a ɛwɔ nnaka a wɔde kyekyɛ nneɛma a ɛwɔ asase so no ho (OGBs).
• Japan, Hong Kong, & India: Wɔ Japan mu no, frɛ 119 ne nkitahodi TEPCO/ .KEPCO. Wɔ Hong Kong mu no, frɛ ** .999** ne nkitahodi ** .CLP Power (2728 8333)** anaa ** .HK Electric (2555 4999)** na ɛyɛ. Wɔ India mu no, frɛ ** .112** ne wo mpɔtam hɔfo DISCOM mmoa telefon (1912).

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Nsɛm a wɔtaa bisa¶

Dɛn nti na transformer adaka a ɛyɛ ahabammono a ɛwɔ me gyaade no reyɛ gyegyeegye kɛse mpofirim wɔ awɔw bere mu ɔhyew mu anaasɛ 6:00 PM?¶

Transformer a wɔde pad ahyɛ mu a ɛyɛ daa no ma ɛyɛ komm na ɛyɛ pintinn 120-hertz na ɛyɛ den hum a ɛnam magnetostriction a ɛwɔ ne dade mu no so ba. Nanso, ntam 4:00 PM ne 9:00 PM bere a awɔw bere mu ɔhyew a ano yɛ den, anaasɛ bere a afipamfo pii de plug no hyɛ mu bere koro mu no Ɔfa 2 (40-kɔsi 80 amp) . Kar a Ɛwɔ anyinam ahoɔden (EV) chargers na run central air conditioners, biako 50 kVA na ɛyɛ adwuma mpɔtam hɔ transformer betumi apia akɔ ɔha biara mu nkyem 140 kosi 180 a ɛfa ne tumi a wɔahyɛ ho akontaa no ho. Sɛ wɔde nneɛma gu mu dodo a, mineral oil a ɛwɔ mu no hyew kɔ soro twam Ɛwɔ digrii Celsius 100 (212 na ɛyɛ digrii Fahrenheit), core laminations wosow denneennen, na emu nkitahodi ahorow no fi ase yɛ arc anaasɛ sizzle. Sɛ hum no dan dede a ano yɛ den, frying-bacon sizzle, anaa dade chatter a, tra hɔ 15 mita (50 anammɔn) san kɔ na frɛ wo anyinam ahoɔden adwumayɛbea no ntɛm ara sɛnea ɛbɛyɛ a wobetumi ahwɛ afiri no mu ansa na apaapae.

Me kraman ho dwiriw no anaasɛ ɔteɛɛm na ohuruw san n’akyi bere a na ɔnam sare a ɛbɛn adaka bi a ɛyɛ ahabammono a wɔde nneɛma di dwuma so no. Deɛn na ɛsiiɛ?¶

Wo kraman no nyaa osuahu contact voltage (stray voltage) anaa asase-mfomso anammɔn tumi. Sɛ asase ase cable insulation nick anaasɛ concentric neutral wire a asɛe no de current kɔ asase a ɛyɛ nwini mu a, voltage gradient ba fam twa kɔnkrit pad no ho hyia. Efisɛ ɔkraman nantew anan a ɛyɛ nsu a ɛda hɔ kwa a ɛtrɛw so 0.5 kosi 0.9 mita (1.5 kosi 3 anammɔn) na ɔwɔ fibrillation threshold a ɛba fam, mpo 15 kosi 50 volts sare no atifi de ahodwiriw a ɛyɛ yaw anaasɛ edi awu ba n’anim ne n’akyi nan ntam. Twe wo kraman san kɔ asphalt a ayow so ntɛm ara, anyɛ yiye koraa no, tra hɔ 10 kosi 15 mita (35 kosi 50 anammɔn) no fi adaka no ho, na frɛ 911. Ɔde ne nsa kyerɛɛ ne so ne wo anyinam ahoɔden adwumayɛbea no de bɔ amanneɛ sɛ asiane a ɛyɛ nnam a ahoɔden wom a ɛma aboa bi ho dwiriw no ara kwa.

So metumi ayɛ transformer adaka a ɛyɛ fɛ a ɛyɛ ahabammono a ɛwɔ m’anim gyaade no ho adwini ma ɛne me fie ahyia anaasɛ mede abotan a ɛyɛ tokuru a ɛnyɛ nokware akata so?¶

Dabi, da transformer a wɔde pad asisi so ho adwini anaasɛ fa fiberglass faux-rock kataso nhyɛ so da. Nea edi kan no, wɔayɛ adwumayɛbea Munsell-green enamel no sɛnea ɛbɛyɛ a ɛbɛma ɔhyew a ɛwɔ mu no afi... 100-degree-Celsius a ɛyɛ digrii Celsius ngo a wɔde gu mu; painting cabinet ne latex ofie paint insulates tank no, kata critical no so Stencil Number a ɛwɔ digit 6 kosi 10 ne kɔkɔbɔ decals a ɛwɔ ahoɔden kɛse, na ɔde gluu gu mframa a wɔde fa mu ano ne penta-bolt latch no mu. Nea ɛto so abien no, sɛ wɔde ɔbotan a ɛyɛ tokuru a wɔde siesie asase no si transformer a ngo ahyɛ mu ma a ɛyɛ adwuma so a, ɛkyere ɔhyew kosi sɛ emu windings no bɛhu amane wɔ ɔhyew aguan na apae. Sɛ paint a ɛwɔ wo mpɔtam hɔ adaka no so no repaapae anaasɛ ɛreyɛ nkannare a, frɛ anyinam ahoɔden adwumayɛbea no: adwumakuw a ɛhwɛ anyinam ahoɔden so no soma adwumayɛfo a wosiesie no ma wɔnkɔhwɛ sɛ ngo a ɛretu anaa na wɔsan de aduru a wɔde kata so a adwumakuw no apene so hyehyɛ kabinet no mu kwa.

Kanea a ɛwɔ me fie no reyɛ ayɛ kusuu na ɛrehuruw kɛse bere a adaka a ɛyɛ ahabammono a ɛwɔ abɔnten no reyɛ gyegyeegye no. Dɛn nti na me fie fã wɔ akanea a ɛhyerɛn yiye?¶

Worenya osuahu bi a "Open Service Neutral". wɔ pad-mounted transformer no secondary compartment mu (anaasɛ wo asase ase service drop no ho). Tumi a ɛwɔ Amerika Atifi fam no hyɛn wo fie sɛ abien 120-volt na ɛyɛ adwuma nan a ɛyɛ hyew ( .240 volts na ɛwɔ hɔ total) a wɔkyɛ grounded center neutral waya. Sɛ saa neutral lug no hyew wɔ transformer adaka a ɛyɛ ahabammono no mu a, abien no 120-volt na ɛyɛ adwuma wo fie fã kyekyɛ voltage mu pɛpɛɛpɛ a egyina mfiri a ɛretu mmirika so, na ɛde kɔ soro kodu 180 kosi 210 volts akɔ wo aguadidan ahorow no fã biako mu (wɔdan bɔlɔb ahorow ma ɛhyerɛn anifuraefo na wɔayam fononoo ntaaboo, frigye, ne surge strips) bere a wode fã a aka no to fam kɔ 30 kosi 60 volts. Sɛ wo dan mu breaker panel no yɛ komm na ɛyɛ nwini a, dannan wo Main Breaker OFF ntɛm ara na frɛ utility no ma wɔbɔ amanneɛ sɛ ntɛmpɛ bue neutral neutral.

Dɛn na cartoon triangle sticker ("Mr. Ouch") a ɛwɔ transformer adaka a ɛyɛ ahabammono no anim no kyerɛ?¶

Kɔkɔbɔ decal a ɛyɛ kɔkɔɔ ne kɔkɔɔ a ɛyɛ ahinanan a ɛkyerɛ anyinam-abɔfo bi a ɛma abofra nsa ho dwiriw no no ne... Ɔman Afiri a Wɔyɛ anyinam ahoɔden Fekuw (NEMA) "Owura Ouch" High-Voltage Asiane Nkyerɛwde, a wɔde sii hɔ wɔ 1980 mfe no mu bere a mmofra ahobammɔ ho nhwehwɛmu kyerɛe sɛ mmofra nkumaa a wontumi nkenkan ade akyi "ASIANE - VOLTAGE A ƐKƆ SO - KEPE OUT". fi awosu mu hu na kwati cartoon anim a ɛhaw adwene no. Bere biara a wubehu "Mr. Ouch" decal wɔ dade adaka a ɛyɛ ahabammono so wɔ gyaade anaa abɔnten so no, ɛsi so dua sɛ enclosure no wɔ mu mfiri a wɔde kyekyɛ nneɛma a ɛma ahoɔden kɛse a edi awu ( .7,200 kosi 34,500 volt) . mmom sen sɛ wɔde telefon a ahoɔden sua anaa cable-TV nhama bɛhyɛ mu.

Obi a ɔyɛ asase ho adwuma de lɔre a wɔde fa nneɛma anaa nea ɔte so a wɔde twa nneɛma akyi kɔɔ transformer adaka a ɛyɛ ahabammono no mu na ɔbɔɔ no fii ne kɔnkrit pad no so kakra, nanso anyinam ahoɔden no da so ara wɔ hɔ. So asiane biara nni ho?¶

Dabi, fa transformer a ɛwɔ pad a wɔasesa anaasɛ ayɛ den no sɛ ntɛmpɛ a ɛde nkwa to asiane mu ntɛm ara sɛ mpɔtam hɔ anyinam ahoɔden da so ara wɔ hɔ mpo a. Bere a kar bi sesa green transformer cabinet mpo 5 kosi 10 sɛntimita (ne kɛse yɛ nsateakwaa 2 kosi 4) wɔ ne kɔnkrit pad, asase ase a ɛyɛ den no so 7,200-volt na ɛyɛ adwuma wɔtwe nhama titiriw a ɛfa kɔnkrit mfɛnsere no mu ba soro no denneennen wɔ dade kabinet anaa kɔnkrit a wobue no ano a ɛyɛ nnam no so, na ɛpaapae rɔba nsateaa a wɔde siw ano no mu anaasɛ ɛpaapae kɔbere fam ahama a ɛda hɔ kwa a wɔde abɔ asɛm no ho no. Wɔ simma anaa nnɔnhwerew kakraa bi mu no,... `7,200-volt` nhama betumi akɔ dade kabinet no mu tẽẽ, na ama adaka no nyinaa ne asase a atwa ho ahyia no anya ahoɔden. Tu fi hɔ `15 meters` (`50 feet`) kɔ akyirikyiri na frɛ `911` ne anyinam ahoɔden adwumayɛbea no ntɛm ara.

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Akwankyerɛ ahorow a ɛfa ho¶

• Pad-mounted green transformer box a ɛpae, ngo ogya, ne kabinet a wɔabue mu asiane
• Stray voltage a ɛwɔ dade mmɔnten so akanea, kwan ho manhole a wɔde kata so, ne akraman a wɔnantew shocks so
• Downed telecommunications fiber anaa coax cable vs. ahoɔden a ɛto so abien tumi a ɛtɔ wɔ kar kwan so nkyerɛkyerɛmu
• Rolling brownouts, voltage sag, ne mfiri compressor ɔhyew ahobammɔ
• Nnɔmba a egye ntɛmpɛ sɛnea ɔman biara te

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Fibea ne aban akwankyerɛ¶

• Asoɛe a Ɛhwɛ Ɛlektrik ne Ɛlektrɔnik Mfiridwuma So (IEEE) & Ɔman Ɛlektrik Ahobammɔ Mmara (NESC): IEEE Std C57.12.28 (Pad-Mounted Adwinnade - Enclosure Integrity), IEEE Std C57.12.25 / C57.12.34 (Gyinapɛn ma Pad-Ahyɛ, Compartmental-Type, Ankasa-Cooled Nkyekyɛmu Nsakrae, 2,500 kVA ne Nketewa; High-Voltage a Ɛyɛ Fɛ 34,500 GrdY/19,920 Volts ne Ase hɔ), ne NESC (IEEE C2) Mmara 380 / Mmara 215 (Pad-Mounted Clearances ne Grounding).
• Adwumayɛ mu Ahobammɔ ne Akwahosan Ho Dwumadibea (OSHA, Amerika): 29 CFR § 1910.269 (Electric Power Generation, Transmission, ne Distribution): *High-Voltage Minimum Bɛn Akwansin, Enclosed Space / Pad-Mounted Hot-Stick Dwumadi, ne Anamɔn / Touch Tumi Equipotential Ahobammɔ *.
• U.S. Asoɛe a Ɛhwɛ Nneɛma a Atwa Yɛn Ho Ahyia So (EPA): ** .40 CFR Part 761 Subpart G (Polychlorinated Biphenyls / PCB Ahotew Ho Nhyehyɛe, §§ 761.120-761.135)** ne ** .40 CFR Part 112 (Oil Pollution Prevention / SPCC Ahwehwɛdeɛ a ɛfa Mineral Oil Electrical Equipment ho)**.
• Ɔman Afiri a Wɔyɛ anyinam ahoɔden Fekuw (NEMA): NEMA Gyinapɛn 260 (Ahobanbɔ Nkyerɛwde a Wɔde Si Pad-Mounted Switchgear ne Transformers, "Mr. Ouch" Ɔmanfo Asiane Kɔkɔbɔ Nhyehyɛe) ne Penta-Ti Ahobammɔ Bolt Tamper-Resistance Nkyerɛkyerɛmu.
• Akwahosan ne Ahobammɔ Ho Dwumadibea (HSE, United Kingdom): Anyinam Ahobammɔ, Nneɛma Pa ne Nea Ɛkɔ So Ho Mmara (ESQCR) 2002 ne * .HSG47 (Asiane a Wɔkwati a Ɛfiri Asase ase Nnwuma ne Nkyekyɛmu Substations)*.