Pehea e hana ai i kahi mea pale pale Surge (SPD)
ʻO ka hiki o kahi SPD ke kaohi i nā overvoltages ma ka pūnaewele hoʻolaha uila ma o ka hoʻohuli ʻana i nā au piʻi he hana ia o nā ʻāpana pale pale, ka hanana mechanical o ka SPD, a me ka pili i ka pūnaewele hoʻolaha uila. Hoʻonohonoho ʻia kahi SPD e kaupalena i nā overvoltages transient a hoʻohuli i kēia au o ka wai, a i ʻole ʻelua paha. Loaʻa iā ia ma hoʻokahi o nā mea laina laina ʻole. I nā ʻōlelo maʻalahi loa, manaʻo ʻia ʻo SPDs e kaupalena i nā overvoltages transient me kahi pahuhopu o ka pale ʻana i nā lako lako a me nā downtime ma muli o ka piʻi ʻana o ka uila i kū i nā hāmeʻa a lākou e pale ai.
ʻO kahi laʻana, e noʻonoʻo i kahi wili wai e pale ʻia e ka kiwahi kōkua kaomi. ʻAʻole hana ka valve relief pressure a hiki i ka loaʻa ʻana o kahi pulse pressure-pressure i ka lako o ka wai. Ke kū kēlā, wehe ka pā a kāwili i ke kaomi keu, i ʻole e hiki i ka huila wai.
Inā ʻaʻole ʻo ka vaʻa hoʻōla, hiki i ke kaomi nui ke hōʻino i ka huila wai, a i ʻole ka loulou no ka pahiolo. ʻOiai ke kūwaho o ke kōkua a hana pono, hiki i kekahi o nā koina kaomi kaomi i ka huila. Akā e hoʻemi ʻia ke kaomi e hōʻino ʻole ai i ka huila wai a i ʻole e hoʻopilikia i kāna hana. Hōʻike kēia i ka hana a SPDs. Hoʻoemi lākou i nā transients i nā pae e hōʻino ʻole a hōʻino paha i ka hana o nā pono uila uila.
Hoʻohana ʻia nā ʻenehana
Hoʻohana ʻia nā ʻenehana pehea i SPDs?
Mai IEEE Std. C62.72: ʻO kekahi mau mea pale pale pale maʻamau i hoʻohana ʻia i ka hana ʻana i nā SPD he varistors (MOVs) metala, nā diode breakdown avalanche (ABD - i ʻike ʻia ma ke ʻano he diode avalanche sagon a i ʻole SADs), a me nā paipu hoʻokuʻu kinoea (GDTs). ʻO Movs ka ʻenehana hoʻohana pinepine ʻia no ka pale ʻana i nā pōʻai uila AC. ʻO ka helu lākiō o ka Mov e pili ana i ka mahele ʻāpana a me kāna ʻano. Ma ka laulā, ʻo ka nui o ka ʻāpana o ke kuea, ʻo ke kiʻekiʻe ka piʻi ʻana o kēia manawa o ka hāmeʻa. ʻO ka Movs ma ke ʻano he geometry āpau a huinahā paha akā hele mai i kahi plethora o nā ana maʻamau mai 7 mm (0.28 ʻīniha) a 80 mm (3.15 ʻīniha). Hoʻololi ka laulā o nā lāki o kēia mau pale pale pale i ka nui a hilinaʻi i ka mea hana. E like me ka mea i kūkākūkā ma mua i kēia paukū, ma ka hoʻopili ʻana i nā Movs i kahi lālani like, hiki ke helu ʻia kahi waiwai i kēia manawa e ka hoʻohui ʻana i nā helu i kēia manawa o kēlā me kēia kanaka Movs e kiʻi i ka helu o ka loli o ka lālani. I ka hana ʻana pēlā, pono e noʻonoʻo i ka hoʻohui ʻana o nā ʻano hana o nā Movs i koho ʻia.
Nui nā kuhiakau i ka mea hea, ka topology, a me ka hoʻohana ʻana o kahi ʻenehana kikoʻī e hoʻopuka ai i ka SPD maikaʻi loa no ka hoʻohuli ʻana i kēia au. Ma kahi o ka hōʻike ʻana i nā koho āpau, ʻoi aku ka maikaʻi o ke kūkā kamaʻilio ʻana no ka helu ʻana o kēia manawa, ka helu ʻana o ka nominal Nānā ʻole ʻia o nā ʻāpana i hoʻohana ʻia i ka hoʻolālā, a i ʻole nā ʻenekini kikoʻī i hoʻoili ʻia, he aha ka mea nui i ka helu SPD i kēia manawa a i ʻole Nominal Discharge Current Rating i kūpono no ka noi.
ʻO kahi wehewehe ākea ākea hou aʻe o kēia mau mea. Hoʻololi ʻokoʻa nā mea i hoʻohana ʻia i SPDs. Eia kahi laʻana o kēlā mau ʻāpana:
Metal oxide varistor (Mov)
ʻO ka maʻamau, ʻo MOVs i loko o kahi kino āpau a huinahā paha o ke kino kiniki ʻoka sinter me nā mea hoʻohui kūpono. ʻO nā ʻano ʻē aʻe e hoʻohana pū ana me nā kinikini tubular a me nā hanana multilayer. Loaʻa i nā varistors nā mea uila uila e pili ana i ke aniani kālā a i ʻole nā mea hao ʻē aʻe. Ua noi ʻia paha nā electrodes i ke kino e ka kānana ʻana a me ke kuhi ʻana a i ʻole nā hana ʻē aʻe e pili ana i ka metala i hoʻohana ʻia. Loaʻa pinepine i nā varistors ka uea a i ʻole nā alakaʻi kī a i ʻole kekahi ʻano o ka hoʻopau ʻana i hiki ke hoʻopaʻa ʻia i ka uila.
ʻO ka hana conduction maʻamau o MOVs nā hopena mai nā hoʻopili semiconductor ma ka palena o nā zinc oxide grains i hana ʻia i ke kaʻina hana hewa. E noʻonoʻo ʻia ka varistor i kahi hāmeʻa multi-junction me nā hua he nui e hana ana i ka hui like like ma waena o nā maʻi. Hōʻike ʻia kahi hiʻohiʻona ʻāpana kolamu o kahi varistor maʻamau i ke kiʻi 1.
He waiwai ka Varistors o ka mālama ʻana i kahi loli uila liʻiliʻi ma o kā lākou mau kikowaena ʻoiai ke kahe o ke kahe e kahe ana ma waena o lākou i loli i mau makahiki he nui. Hāʻawi kēia hana nonlinear iā lākou e hoʻohuli i ke au o kahi piʻi ke hoʻopili ʻia i ka shunt ma o ka laina a kaupalena i ka uila ma o ka laina i nā waiwai e pale ai i nā lakohana e pili ana i kēlā laina.
Hōʻailona Breakdown Avalanche (ADB)
ʻIke ʻia kekahi o kēia mau manaʻo ma ke ʻano he diagonal avalanche sagon (SAD) a i ʻole suppressor voltage transitor (TVS). ʻO ka diode breakdown PN junction, ma kona ʻano kumu, kahi huina PN hoʻokahi e pili ana i kahi anode (P) a me kahi cathode (N). E nānā i ke kiʻi 2a. I nā noi kaapuni DC, huli kipi ka mea pale i mea e hoʻohana ʻia ai kahi kūpono kūpono i ka ʻaoʻao cathode (N) o ka hāmeʻa. E nānā i ke kiʻi 2b.
ʻEkolu mau ʻāpana hana o ka diode avalanche, 1) bias bias (low impedance), 2) off state (high impedance), and 3) reverse bias breakdown (impedance haʻahaʻa loa). Hiki ke ʻike ʻia kēia mau ʻāpana i ke kiʻi 3. Ma ke ʻano bias mua me kahi uila maikaʻi ma ka ʻāina ʻo P, loaʻa ka impedance haʻahaʻa loa o ka diode ke piʻi ka voltage ma mua o ka voltage diode bias diode, VFS. ʻOi aku ka emi o ka VFS ma mua o 1 V a wehewehe ʻia ma lalo. Hoʻonui ʻia ka mokuʻāina mai 0 V a i lalo pono o kahi VBR maikaʻi ma ka ʻāina ʻo N. I kēia māhele, ʻo nā kahawai wale nō e kahe ana nā kahe wela kaukaʻi a me nā kahe o Zener tunneling no nā diode uila haʻahaʻa haʻahaʻa. Hoʻomaka ka ʻāpana hōʻoki hope hoʻohuli me kahi VBR maikaʻi ma ka ʻāina ʻo N. Ma VBR electrons keʻa i ka huina e hōʻeleu lawa e ka kiʻekiʻe kahua i loko o ka huina māhele o ka electron collision hopena i ka cascade, a i ʻole avalanche, o nā electrons a me nā lua i hana ʻia. ʻO ka hopena he kulu ʻoi loa i ke kūpaʻa o ka diode. Hiki ke hoʻohana ʻia nā ʻaoʻao i mua a me nā ʻaoʻao hoʻohauna hope bias bias no ka pale ʻana.
ʻO nā ʻano uila o kahi diode avalanche intrinsically asymmetric. Hana ʻia nā huahana palekana symmetric avalanche diode protection ʻo ia hoʻi o nā hope i hope.
Gas Tube hoʻokuʻu (GDT)
ʻO nā paipu hoʻokuʻu kinoea i loko o ʻelua a ʻoi mau electrode metala i hoʻokaʻawale ʻia e kahi wahi liʻiliʻi a paʻa ʻia e ka paukū keramika a me ke aniani. Hoʻopiha ʻia ka paukū i kahi hui kinoea hanohano, i hū ʻia i loko o kahi hoʻokuʻu glow a i kahi hopena arc ke hoʻopili ʻia ka uila i nā uila.
Ke piʻi lohi ka piʻi ʻana o ke anakahi ma ke āpau i kahi waiwai i hoʻoholo nui ʻia e ka electrode spacing, ke kaomi ʻino a me ka hui kinoea, hoʻomaka ke kaʻina hoʻohuli huli i ka uila uila (breakdown). I ka manawa e kū ai ka spark-over, hiki i nā mokuʻāina hana like ʻole, ke kaukaʻi ʻia i ka puni waho. Hōʻike ʻia kēia mau mokuʻāina i ke Kiʻi 4. Ma nā kahawai i emi iho ma mua o ke aniani o ke alohilohi-i-arc, aia kahi ʻāpana glow. I nā kahawai haʻahaʻa i ka ʻāpana glow, aneane mau ka uila; i nā kahe o ke aniani kiʻekiʻe, hiki i kekahi ʻano o nā paipu kōkō ke komo i kahi ʻāpana kukui ʻino kahi e hoʻonui ai ka uila. Ma waho aʻe o kēia māhele ʻālohilohi ʻole e hōʻemi ana ka impedance tube tube i ka māhele hoʻololi i loko o ke kūlana arc haʻahaʻa haʻahaʻa. ʻOi aku ka haʻahaʻa o ke au o ke arc-to-glow ma mua o ka hoʻololi o ka glow-to-arc. ʻO ke ʻano uila GDT, i hui pū ʻia me ka circuitry kūwaho, hoʻoholo i ka hiki o ka GDT e kinai ma hope o ka hele ʻana o kahi piʻi, a hoʻoholo pū kekahi i ka ikehu i hoʻopau ʻia i ka arrester i ka wā o ka piʻi.
Inā piʻi wikiwiki ka uila i noi ʻia (e laʻa me ka manawa kuʻi), hiki i ka manawa i lawe ʻia no ke kaʻina hana ionization / arc ke ʻae i ka volter transient e ʻoi aku i ka waiwai i koi ʻia no ka haki ʻana i ka paukū i hala. Hoʻomaopopo ʻia kēia uila e like me ke anakahi uila breakdown
ʻO kahi lumi hoʻokahi ʻekolu-uila electrode GDT he ʻelua mau lua i hoʻokaʻawale ʻia e kahi uila uila waena. ʻO ka lua ma ka uila uila waena e ʻae i ka plasma gas mai kahi lua e alakaʻi ai e hoʻomaka i ka conduction i ka lua ʻē aʻe, ʻoiai aia ma lalo o ka uila uila.
Ma muli o kā lākou hana hoʻololi a me nā hana paʻa, hiki i nā GDT ke ʻoi aku i nā ʻāpana SPD ʻē aʻe i ka hiki ke hāpai i kēia manawa. Hiki i nā leka uila he nui GDT ke hali maʻalahi i nā kai eʻe i kiʻekiʻe ma 10 kA (8/20 µs nalu). Eia hou, ke kaukaʻi nei i ka hoʻolālā a me ka nui o ka GDT, hiki ke hoʻokō ʻia nā kahe piʻi o> 100 kA.
ʻO ke kūkulu ʻia ʻana o nā paipu hoʻokuʻu kinoea he mea haʻahaʻa loa ia - ma lalo o 2 pF. ʻAe kēia i kā lākou hoʻohana i nā noi kaapuni pinepine pinepine.
Ke holo ʻo GDT, hana paha lākou i ka radiation radiation pinepine, i hiki ke hoʻohuli i ka uila uila. No laila he naʻauao e waiho i nā kaapuni GDT ma kahi mamao mai ka uila uila. Aia ka mamao i ka noʻonoʻo o ka uila a pehea ka pale o nā uila uila. ʻO kahi hana ʻē aʻe e pale i ka hopena e waiho i ka GDT i loko o ka pā pale.
Nā wehewehe ʻana no GDT
ʻO kahi āpau, a i ʻole kekahi mau hakahaka me nā electrode metala ʻelua a ʻekolu paha i hoʻopaʻa ʻia i mea e hoʻomalu ʻia ai ka hui kinoea a me ke kaomi, i hoʻomākaukau ʻia e pale i nā hāmeʻa a i ʻole nā limahana, a i ʻole nā mea ʻelua, mai nā uila kuewa kiʻekiʻe.
Or
ʻO kahi āpau a i ʻole nā hakahaka i loko o kahi pāpaho hoʻokuʻu i hoʻopaʻa ʻia, ʻē aʻe ma mua o ka ea ma ka lewa uila, i hoʻolālā ʻia e pale i nā hāmeʻa a i ʻole nā limahana, a i ʻole nā mea ʻelua, mai nā volta transient kiʻekiʻe.
- Nā kānana LCR
Kūlike kēia mau mea i kā lākou:
- hiki i ka ikehu
- loaʻa
- pono
- kāki
- maikaʻi
Mai IEEE Std C62.72: ʻO ka hiki o kahi SPD e kaupalena i nā overvoltages ma ka pūnaewele hoʻoili uila ma o ka hoʻohuli ʻana i nā au piʻi he hana ia o nā ʻāpana pale pale, ka hanana mīkini o ka SPD, a me ka pili i ka pūnaewele hoʻolaha uila. ʻO kekahi mau mea pale pale pale i hoʻohana pinepine ʻia i ka hana ʻana i nā SPDs he Movs, SASDs, a me nā paipu hoʻokuʻu kinoea, me nā Movs me ka hoʻohana nui. ʻO ka helu lākiō o ka Mov e pili ana i ka mahele ʻāpana a me kāna ʻano. Ma ka laulā, ʻo ka nui o ka ʻāpana ʻāpana, ʻo ke kiʻekiʻe ka helu o ka hāmeʻa o kēia hāmeʻa o ka hāmeʻa. ʻO ka Movs maʻamau o ka geometry āpau a huinahā paha akā hele mai i kahi plethora o nā ana maʻamau mai 7 mm (0.28 i) a 80 mm (3.15 i). Hoʻololi ka laulā o nā lāki o kēia mau pale pale pale i ka nui a hilinaʻi i ka mea hana. Ma ka hoʻohui ʻana i nā Movs i kahi lālani like, hiki ke helu ʻia kahi helu lākiō theoretical i kēia manawa me ka hoʻohui ʻana i nā helu i kēia manawa o kēlā me kēia Movs pū kekahi e loaʻa ai ka helu helu o kēia lā o ka lālani.
Nui nā kuhiakau i ka mea hea, ka topology, a me ka hoʻohana ʻana o kahi ʻenehana kikoʻī e hoʻopuka ai i ka SPD maikaʻi loa no ka hoʻohuli ʻana i kēia au. Ma kahi o ka hōʻike ʻana i kēia mau paio āpau a waiho i ka mea heluhelu e wehewehe i kēia mau kumuhana, ʻoi aku ka maikaʻi o ke kūkā kamaʻilio ʻana no ka pane ʻana i kēia manawa, ka helu ʻana i kēia manawa, a i ʻole nā hiki i kēia manawa e hoʻopuni i ka ʻikepili hōʻike hana. Nānā ʻole i nā ʻāpana i hoʻohana ʻia i ka hoʻolālā, a i ʻole nā ʻenekini kikoʻī i hoʻoili ʻia, he aha ka mea nui i ka helu SPD i kēia manawa a i ʻole Nominal Discharge Nānā Hou e kūpono no ka palapala noi a, ʻo ka mea nui paha, ʻo ka SPD ka palena o ka mea kuewa. nā overvoltages i nā pae e pale ai i ka hōʻino ʻana i nā lakohana i pale ʻia i hāʻawi ʻia i kahi kaʻe e manaʻo ʻia.
Nā Kūlana Hana Maʻamau
ʻO ka hapa nui o nā SPD he ʻekolu mau ʻano hana maʻamau:
- Ke kali nei
- E hoʻohuli ʻana
I kēlā me kēia ʻano, kahe i kēia manawa ma o ka SPD. Eia naʻe ka mea e maopopo ʻole ai, hiki i kahi ʻano ʻokoʻa o ke au ke kū i kēlā me kēia ʻano.
Ke ʻano kali kakali
Ma lalo o nā kūlana mana maʻamau ke hāʻawi ʻia ka "mana maʻemaʻe" i loko o kahi ʻōnaehana hoʻoili uila, hana ka SPD i ka hana liʻiliʻi. I ke ʻano kali, ke kali nei ka SPD no ka hopena o kahi overvoltage a ke hoʻopau nei i ka mana ac a liʻiliʻi paha; ʻo ka mea i hoʻohana ʻia e nā kaapuni nānā.
Ke ʻano hoʻololi
Ke ʻike nei i kahi hanana overvoltage transient, hoʻololi ka SPD i ka Diverting Mode. ʻO ke kumu o ka SPD e hoʻohuli i ka manaʻo hoʻohaunaele i kēia manawa mai nā kaumaha koʻikoʻi, ʻoiai e hoʻoliʻiliʻi ana i ka nui o ka nui o ka uila i kahi pae haʻahaʻa, maikaʻi ʻole.
E like me ia i ho'ākāka ʻia e ANSI / IEEE C62.41.1-2002, kahi mahele maʻamau o kēia manawa wale nō kahi hapa o kahi pōʻaiapuni (microseconds), kahi ʻāpana o ka manawa ke hoʻohālikelike ʻia me ke kahe mau o kahi 60Hz, hōʻailona sinusoidal.
ʻO ka nui o ke au e kaukaʻi ʻia ana i kāna kumu. Kū ka uila, no ka laʻana, hiki i nā hanana laha ʻole ke loaʻa nā nui o kēia manawa i ʻoi aku ma mua o nā haneli tausani amp. Ma loko o kahi keʻena, eia naʻe, e hana nā hanana kuʻuna i hana ʻia i lalo i nā nui o kēia manawa (ma lalo o kahi mau kaukani a i ʻole haneli amps).
No ka mea ʻo ka hapa nui o nā SPD i hoʻolālā ʻia e lawelawe i nā au kahe nui, hoʻokahi pae hana i hoʻāʻo ʻia ka huahana nominal Discharge Rating Rating (In). Huikau pinepine me ka hewa o kēia manawa, akā pili ʻole, kēia nui nui o kēia manawa kahi hōʻailona o ka huahana i hōʻoia hou ʻia me ka hiki ke kū.
Mai IEEE Std. C62.72: Hoʻomaʻamaʻa ka Nominal Discharge Current Rating i ka hiki i ka SPD ke hoʻoiho ʻia i nā piʻi o kēia manawa (15 ka nui o nā piʻi) o kahi waiwai i wae ʻia me ka ʻole o ka pohō, hoʻohaʻahaʻa a hoʻololi paha i ka ana ʻana i ka hana uila o ka SPD. ʻO ka hoʻāʻo Nominal Discharge o kēia manawa e pili ana i ka SPD holoʻokoʻa me nā ʻāpana pale pale āpau a me nā disconnector SPD kūloko a i waho paha. I ka wā o ka hoʻāʻo ʻana, ʻaʻohe ʻae a disconnector paha e ʻae e holo, wehe i ke kaapuni, e hōʻino a hōʻino paha. I mea e hoʻokō ai i kahi helu kikoʻī, pono e mālama ʻia ke ana ana i ka pae hana uila o ka SPD ma waena o ka hoʻokolohua mua a me ka hoʻohālikelike post-test. ʻO ke kumu o kēia mau hoʻāʻo e hōʻike i ka hiki a me ka hana o kahi SPD i ka pane ʻana i nā ʻūlū i kekahi mau hihia koʻikoʻi akā e manaʻo ʻia paha ma nā lakohana lawelawe, ma loko o kahi wahi a i ʻole kahi hoʻonohonoho.
ʻO kahi laʻana, he SPD me kahi mana hoʻokuʻu kū i kēia manawa o 10,000 a i ʻole 20,000 amps no ka mode ʻo ia hoʻi ka huahana e hiki ke pale aku me ka palekana o ka nui o 10,000 20,000 a i ʻole 15 amps ma ka liʻiliʻi o XNUMX mau manawa, i kēlā me kēia ʻano o ka pale.
Nā Scenarios Pau o ke Ola
Mai ka IEEE Std C62.72: ʻAʻole paha he piʻikoʻi ka hoʻoweliweli nui loa i ka hilinaʻi lōʻihi o nā SPD, akā ʻo nā manawa hou a i ʻole nā manawa pōkole (TOVs a i ʻole "swells") e hiki ke hana ma ka PDS. ʻO nā SPD me kahi MCOV - pili kokoke loa i ka volta ʻōnaehana nominal hiki ke maʻalahi ʻia i nā ʻano overvoltages i hiki ke alakaʻi i ka ʻelemakule SPD a i ʻole ka hopena hopena mua. ʻO kahi lula o ka manamana lima e hoʻohana pinepine ʻia e hoʻoholo inā ʻo ka MCOV o ka SPD ma ka liʻiliʻi 115% o ka volter ʻōnaehana nominal no kēlā me kēia ʻano palekana. E ʻae kēia i ka SPD e hoʻopili ʻole ʻia e nā loli uila maʻamau o ka PDS.
Eia nō naʻe, koe aʻe o nā hanana overvoltage hoʻomau ʻia, hiki i nā SPD ke ʻelemakule, a hoʻohaʻahaʻa paha, a hōʻea i ko lākou hopena o ka lawelawe ma o ka manawa ma muli o nā piʻi i ʻoi aku i nā helu SPD no kēia manawa piʻi, ka helu o ka hanana o nā hanana piʻi, ka lōʻihi o ka piʻi ʻana , a i 'ole ka hui' ana o kēia mau hanana. Hiki i nā hanana piʻi pinepine o ka amplitude nui ma kahi o ka manawa ke wela i nā ʻāpana SPD a hana i nā ʻāpana pale pale i ka makahiki. Eia hou, hiki i nā piʻi pinepine ke hana i nā disconnector SPD i hoʻoulu ʻia thermally e hana prematurely ma muli o ka hoʻomehana ʻana o nā mea pale pale. Hiki ke hoʻololi i nā ʻano o ka SPD ke hiki i kona hopena o ka lawelawe - no ka laʻana, hiki ke hoʻonui a hōʻemi paha nā ana palena palena i ana ʻia.
I ka hoʻāʻo ʻana e hōʻole i ka hoʻohaʻahaʻa ma muli o nā nalu, hana nui nā mea hana SPD i nā SPD me nā hiki i kēia manawa kiʻekiʻe e hana ʻia i nā mea i ʻoi aku ka nui a i ʻole ma ka hoʻopili ʻana i nā mea he nui i ka like. Hana ʻia kēia i mea e hōʻalo ai i ka likelika o nā helu helu o ka SPD ma ke ʻano he hui i ʻoi aku ma kahi o nā hanana kakaikahi a me nā mea ʻē aʻe. Kākoʻo ʻia ka kūleʻa o kēia hana e ke ola lawelawe lōʻihi a me ka mōʻaukala o nā SPD e kū nei i hoʻonohonoho ʻia i kēia ʻano.
E pili ana i ka hoʻohui ʻana o SPD a, e like me ka ʻōlelo e pili ana i ka piʻi ʻana o ka helu i kēia manawa, kūpono i ka loaʻa ʻana o kahi SPD me nā helu kiʻekiʻe o kēia manawa e kū nei ma nā pono lawelawe kahi e hōʻike nui ʻia ai ka PDS i nā piʻi e kōkua ai i ka pale ʻana i ka ʻelemakule ʻōpio. ʻoiai, ʻo SPD hou aʻe ka laina laina mai nā lakohana lawelawe i hōʻike ʻole ʻia i nā kumuwaiwai kūwaho o nā piʻi i loaʻa nā helu liʻiliʻi liʻiliʻi. Me ka hoʻolālā ʻōnaehana pale pale maikaʻi maikaʻi e hiki ke hōʻalo ʻia.
ʻO nā kumu ʻē aʻe o ka hoʻokō ʻole o SPD:
- Nā hemahema hoʻonoho
- Hoʻohana hewa ʻole i kahi huahana no ka helu uila
- Nā hanana i hoʻonui ʻia me ka uila
Ke holo pono ʻole kahi mea kaomi, hana pinepine ia ma ke ʻano he pōkole, e hoʻomaka ana i ke kahe e holo i loko o ka mea i kū ʻole. Loaʻa ka nui o ke kū i kēia manawa e kahe ma o kēia mea i kō ʻole ʻia kahi hana o ke au hewa i loaʻa a hoʻokele ʻia e ka ʻōnaehana mana. No ka ʻike hou aku e pili ana i nā Fault Fault e hele i ka ʻike pili pili pili iā SPD.
