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Ky thuat an toan khi van hanh thiet b tieu thu
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I-Phan loai cac thiet b dung ien:Tt c cc thit b in c phn loi
theo in p nh hn 1000 V hoc ln hn. Cn lu l in p c coi l an ton l nh
hn 36 , cn dng mt chiu l 48 V. Tuy nhin nu khng tun th qui tc an
ton khi tin hnh cng vic c th xy cht ngi ngay c khi p l 36 V v 12 V.
Cc bin php t chc v k thut khi tin hnh cng vic trn thit b in cn ph
thuc vo a im, in p v chc nng ca thit b in. V mt bo v cch in ca thit
b in v an ton cho ngi , a im cha thit b in c phn loi ph thuc vo mi
trng (bng 1) v mc nguy him khi b chm in
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II- An toan cua cac thiet b iena-May bien ap:Qua tai: Bao ve
chong qua tai c thc hien bang cach s dung rle qua tai co tre (hoac
la loai rle nhiet co thanh lng kim hoac thiet b ien t). Bao ve nay
se tac ong cat mach pha au ra cua MBA. Thi gian tre nay nham am bao
khong cat nham MBA trong trng hp qua tai ngan han.Cac hnh thc bao
ve khac:- oi vi loai may bien ap kieu treo, rle nhiet thng c s
dung. Cac rle nay cam nhan nhiet o cuon day MBA vi mc chnh xac u e
am bao an toan cho cach ien. - oi vi may bien ap kho se s dung bo
cam bien nhiet o c cai phan nong nhat cua cach ien cac cuon day e
bao tn hieu va tac ong cat may bien ap.Cac may bien ap lam mat bang
dau co cong suat ln thng co cac thermostat vi hai tr so at, mot e
bao tn hieu va mot e cat may bien ap.
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Cac s co ben trong may bien ap:
Bao ve may bien ap chong cac dang s co ben trong thung dau may
bien ap c thc hien oi vi may bien ap co thung dau phu va thng s
dung rle c loai Buchholz. Cac rle nay co the kiem tra s tch tu cham
hi do dau may bien ap boc do ho quang xuat hien cho cham cac cuon
day v h hong cach ien, hoac do s xam nhap cua khong kh khi dau b
ro. Rle hi mc mot thng cho tn hieu bao ong, mc hai se tac ong cat
may cat pha s cap. Kha nang kiem tra ot bien ve s boc hi cua dau
may bien ap trong rle Buchholz cho phep cat may cat nam pha s cap
may bien ap mot cach tc thi neu xung dau xay ra trong ong noi thung
dau phu va chnh.S ot bien ve xung do dch chuyen dau ch co the xay
ra do s tao bot kh gay bi ho quang dong ngan mach trong dau.
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Cac s co ben trong may bien ap:Tat ca may bien ap eu c lap vai
loai rle bo sung loai qua ap suat nham gii han s tang ap suat dau
ti mc ln co the gay pha huy thung may bien ap.Vi loai may bien ap
cong suat ln 10MVA hien nay, he thong tan nhiet lam mat c thiet ke
kieu oi lu. Do o s dan dau se khong gay nen tang ap suat, nh cac
canh tan nhiet . Trong trng hp nay rle hi kieu Buchholz khong ap
dung c, ngi ta s dung thiet b bao ve DGPT gom cac chc nang: - kiem
tra lng hi boc ra;- kiem tra qua ap suat; - kiem tra qua nhiet o.
Hai ieu kien au se tac ong may cat pha s cap bien ap con ieu kien
th ba se cat may cat pha th cap.
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Bao ve ngan mach Khi cuon ha ap cua may bien ap noi sao co trung
tnh khong noi at, may bien ap cung cap ien cho mang kieu IT thng co
thiet b bao ve chong qua ien ap. Thiet b nay se tac ong e noi trung
tnh cuon ha cua may bien ap trc tiep xuong at. S co cham at pha
cuon day s cap co the gay nguy hiem do ien ap lan truyen sinh ra .
V ly do nay, bao ve chong cham at co o nhay va toc o cao c coi la
tieu chuan oi vi pha s cap cua may bien the phan phoi cong cong va
bien the phan phoi khach hang. S o tren hnh C17 co the ap dung oi
vi may bien ap co cuon s cap noi tam giac hoac sao trung tnh khong
noi at. S o nay c goi la Bao ve chong cham at co gii han
(Restricted Earth Fault).
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Bao ve ngan mach Tnh chon loc gia cac thiet b bao ve pha trc va
sau may bien ap.e am bao tnh chon loc toan bo ng ac tnh cua cau ch
trung the phai nam tren va ben phai cua ng ac tuyen CB ha the.e am
bao cau ch trung the khong b anh hng:- pham vi tien ho quang toi
thieu ng vi ac tnh cua cau ch trung the can nam ben phai ac tnh lam
viec cua CB tng ng bang 1,35 hoac ln hn (v du tai thi iem T, ng ac
tnh cua CB tng ng tr so tac ong 100A th cau ch trung the phai co tr
so dong tac ong la 135A hoac ln hn,.v.v.);- thi gian tac ong cua
cau ch trung the so vi CB ha the phai ln hn gap 2 lan tai mot tr so
dong ien. V du khi dong ien la I, theo ac tuyen cua CB th thi gian
tac ong la 1,5s, tng ng vi dong I nay, theo ac tuyen cua cau ch thi
gian tac ong phai la 3s (giay).Cac he so 1,35 va 2 da tren tieu
chuan ve sai so che tao ln nhat cua cau ch trung the va CB ha
the
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b-Tu ienTu ien c bao ve hoan hao (s dung phan t bao ve chong ap
lc qua cao ket hp vi cau ch HPC), cho phep ngat tu khi xay ra s co
ben trong.S o bao ve tu hoat ong nh sau:- mot s ngan mach qua ien
moi se lam chay cau ch;- dong ien at gia tr ln hn mc bnh thng nhng
cha u lam chay cau ch do xuat hien dong nho trong lp mang ien moi.
Cac s co o thng b bt kn lai do tac dung nhiet bi dong ro. Luc o, ta
noi tu t phuc hoi. Neu dong ien ro duy tr tiep tuc, s co tren co
the phat trien dan en hien tng ngan mach va lam chay cau ch.chat kh
xuat hien do hien tng boc hi kim loai tai iem co s co se dan dan
lam tang ap lc ben trong vo va ket qua la mot linh kien nhay vi ap
suat se tac ong tao nen ngan mach lam cho cau ch b t. Tu ien che
tao t vat lieu cha hai lp cach ien, v the tu khong can noi at.
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Mat cat mot phan t cua tu
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c- Cac ong c khong ong boCac chc nang bao ve va ieu khien can
thiet.Cac chc nang thng la:+ bao ve c ban, bao gom:- cach ly mot
cach de dang;;- ieu khien bang tay gan va /hoac t xa;- bao ve chong
ngan mach;- bao ve chong qua tai.+ thiet b ieu khien ien t bao
gom:- khi ong mem ong c, hoac- ieu khien toc o.+ thiet b bao ve
phong nga hay gii han bao gom:- cam ng nhiet;- rle a nang;- kiem
soat ien tr cach ien thng xuyen hay RCD (thiet b so lech dong
ro).
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c- Cac ong c khong ong boCac s o bao ve c ban: CB / cong tac t /
rle nhietu iemTo hp cac thiet b nay tao ieu kien de dang cho viec
lap at, cung nh hoat ong va bao tr, nh vao:+ giam chi ph bao tr: CB
giup tranh phai thay cau ch b no va lu kho (cac loai);+ hoat ong
lien tuc tot hn: mach ong c co the cap ien lai tc thi sau khi s co
c loai tr;+ cac thiet b phu tr sau nay co the de dang them vao;
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c- Cac ong c khong ong bo+ bao am ngat c ca 3 pha, do o tranh c
kha nang con mot pha hoat ong;+ kha nang cat dong ay tai (bang CB)
trong trng hp s co cong tac t, v du nh dnh tiep diem;+ khoa lien
ong;+ cac tn hieu canh bao va ch th khac nhau;+ bao ve khi ong tot
hn trong trng hp dong ngan mach khoang 30In
Trong phan ln cac trng hp s co ngan mach xay ra tai ong c, do o
dong b gii han bi cap va day quan trong bo khi ong (v du nh cuon
ngat hoat ong trc tiep cua CB).+ kha nang them vao RCD:- mot RCD co
o nhay 500mA thc te loai tr nguy hiem chay do dong ro;- bao ve
chong lai pha huy ong c bang cach phat hien sm dong ro at (300mA ti
30A);
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c- Cac ong c khong ong boBao ve phong nga hoac gii hanThiet b
bao ve phong nga hoac gii han phat hien cac dau hieu s co sap xay
ra e tien hanh thao tac (t ong hoac do ngi) nham tranh hoac han che
cac hau qua xau.Cac thiet b bao ve thuoc loai nay cho ong c la:-
cam bien nhiet trong ong c (cuon day, vong bi, ong dan kh lam mat,
v.v);- bao ve a chc nang;- thiet b phat hien h hong cach ien trong
ong c ang chay hoac ng yen.Cam bien nhietCam bien nhiet c dung e
phat hien s tang nhiet bat thng trong ong c bang cach o trc
tiep.Cam bien nhiet thng c gan chm trong cuon stator (cho ong c ha
the), tn hieu c x ly nh mot thiet b ieu khien dan en tac ong
CB.
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c- Cac ong c khong ong boR-le bao ve ong c a chc nangR-le a chc
nang cung vi mot so cac mo un cam bien va ch th cho phep bao ve ong
c khi:- qua tai nhiet;- rotor ket, hoac thi gian khi ong qua lau;-
qua nong;- mat can bang pha, mat mot pha, quay ngc;- s co cham at
(nh RCD);- chay khong tai, ong c ket khi khi ong;u iem cua r-le nay
chu yeu la:- bao ve rong, thc hien chc nang kiem soat tin cay, chat
lng cao va thng xuyen;- giam sat hieu qua tat ca cac tien trnh thao
tac ong c;- ch th bao ong va ieu khien: - kha nang giao tiep qua ng
truyen thong tin.
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Bao ve phong nga cho ong c trang thai dngLoai bao ve nay lien
quan en viec kiem soat mc ien tr cach ien cua ong c trang thai dng,
nh o tranh c hau qua xau cua s co trong hoat ong, nh la:- oi vi ong
c s dung trong cac tnh huong khan cap v du nh: tranh c s co khi khi
ong hoac tao c s hoat ong thoa ang; - trong san xuat: tranh h hong
san pham.Loai bao ve nay can cho cac ong c hoat ong trong tnh trang
s co hoac khan cap, ac biet trong ieu kien am t va /hoac bui
bam.Bao ve loai nay tranh c s pha huy ong c do ngan mach cham at
khi khi ong (mot s co pho bien) bang cach canh bao trc rang can
tien hanh bao tr e phuc hoi ong c tr lai mc hoat ong va y.
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Bao ve gii hanCac thiet b bao ve so lech dong ro (RCD) co the
rat nhay va phat hien c cac gia tr nho cua dong ro xay ra khi cach
ien vi at cua mot he thong b thoai hoa (do h hong, an mon, o am,
cao, v.v). Mot so RCD thiet ke ac biet cho cac ng dung o con cho
phep:- tranh h hai ong c (do thung hoac ngan mach thep la cua
stator) gay ra do s co phong ho quang xuong at. Bao ve loai nay co
the phat hien cac ieu kien s co bang cach tac ong vi mc dong ro
trong khoang 300mA ti 30A, tuy theo kch c cua ong c (o nhay khoang
5% In). Cat tc thi do RCD se gii han mc o ton that tai iem xay ra s
co. giam nguy hiem chay do dong ro cham at (o nhay 500mA). RCD tieu
bieu cho cac chc nang loai nay la r-le RH328A (Merlin Gerin) vi:.
32 o nhay (0.03 ti 250A);. co the ngat chon loc hoac tnh en cac yeu
cau thao tac ac biet, da tren 8 khoang tre co the (tc thi cho en
1s);. hoat ong t ong neu mach t bien dong ti rle b ngat;. chong
hoat ong nham;. cach ien cac thanh phan mach d.c: loai A.
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e-UPSKhi chon s o bao ve can tnh en cac ac tnh cua he UPS: dong
ngan mach t he UPS luon b gii han, oi khi nho hn hai lan dong nh
mc. Cac nha san xuat tien hanh th nghiem e am bao s phoi hp gia cac
tnh nang cua he UPS va s bao ve bang cac CB.Chon nh mc cat cua
CBDong nh mc cat In cua CB D1, D2, D3 va Ddc phai c chon sao cho:In
I1 cho D1 (I1 bao gom dong nap lai cua ac qui)In Iu cho D2In Ide
cho DdcDong nh mc In cho moi CB D3 tuy thuoc vao dong nh mc cua tng
mach cu the.
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f-Tu ien tai tram Lien ong va cac ieu khien co ieu kienNhng lien
ong trong tram c lap at thiet b ong cat co vo boc bang kim
loaiTrong tram bien aptrung /ha gom co:+ mot panel lo vao trung ap
hoac 2 panel lo vao (t 2 ng day song song) hoac 2 panel ieu khien
vao /ra kieu mach vong;+ mot panel ong cat cua may bien the va mach
bao ve. Panel nay co the gom dao cat tai /hoac dao cach ly vi cau
ch trung the va dao tiep at hoac may cat va dao cach ly pha ng day
cung vi dao tiep at;+ ngan khoa lien ong cua may bien ap cho phep
cac thao tac va tiep can cac panel khac theo ieu kien sau:- van
hanh dao cat tai hoac dao cach ly khi ca panel ong va dao noi at
lien quan m;- van hanh dao cach ly ng day cua panel ong cat va bao
ve may bien ap neu ca panel c ong va ch khi may cat a m va cac dao
tiep at m;- ong dao tiep at ch thc hien c khi dao cach ly co lien
quan ang m *- tien can ben trong cua tng panel ch thc hien c khi
dao cach ly cua panel m va dao tiep at ben trong panel ong;- ong ca
panel hoac ngan ch thc hien c khi dao tiep at trong panel ang ong;-
tiep can vi cau ch trung the cua tram c cap nguon t 2 ng day song
song ch thc hien c khi hai dao cach ly m va 2 dao tiep at trong
panel ong;- tiep can vi ngan co bien ien ap ch thc hien c khi dao
cach ly trung the m va khi thiet b cach ly pha ha ap a m;- van hanh
dao cach ly trong panel bien ien ap ch khi ca panel a c ong.
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Mot s o lien ong bat ky
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f-Tu ien tai tram(*) Neu dao tiep at at lo vao, cac dao cach ly
tng ng ca hai au cua lo can co s lien ong thch hp.V du thc
hanhTrong mot tram bien ap khach hang vi phan o lng ha the, s o
lien ong c s dung rong rai nhat la trung ap / ha ap / may bien
apMuc ch cua lien ong la:- ngan nga tiep can tu may bien ap neu dao
tiep at cha c ong;- ngan nga viec ong dao tiep at cua panel bao ve
va ong cat may bien ap khi thiet b ong cat pha ha the cua may bien
ap cha c khoa v tr m hoac keo ra khoi ngan (withdrawn)Tiep can au
trung hoac ha ap cua mot may bien ap c bao ve pha s cap bang panel
ong cat bao ve co cha dao cat tai hoac dao cach ly, cau ch trung
the va dao tiep at phai tuan theo quy trnh nghiem ngat sau ay va c
minh hoa tren hnh C24.Ghi chu: May bien ap trong v du nay c cung
cap bo noi kieu au cam pha s cap va ch co the thao ra c bang cach m
khoa mot thiet b gi chung cho ca bo noi 3 pha (*).
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f-Tu ien tai tramTiep can au trung hoac ha ap cua mot may bien
ap c bao ve pha s cap bang panel ong cat bao ve co cha dao cat tai
hoac dao cach ly, cau ch trung the va dao tiep at phai tuan theo
quy trnh nghiem ngat sau ay va c minh hoa tren hnh.Ghi chu: May
bien ap trong v du nay c cung cap bo noi kieu au cam pha s cap va
ch co the thao ra c bang cach m khoa mot thiet b gi chung cho ca bo
noi 3 pha (*).Dao cach ly hay dao cat tai pha trung the la lien ong
c kh vi dao tiep at pha trung the va ch c lien ong vi mot dao, ngha
la khi ong mot dao, t ong se khoa viec ong dao kia.(*) hoac co the
c trang b mot nap bao ve chung tren 3 au cc.
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f-Tu ien tai tramQua trnh cach ly, tiep at may bien ap lc va
thao cac au noi kieu au cam (hoac nap bao ve).Cac ieu kien ban au:-
cac dao cat tai hoac dao cach ly pha trung the va CB pha ha the ang
ong;- dao tiep at trung the khoa v tr m bang cha O;- cha O c gi
trong CB ha ap trong khi CB nay ang ong.
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f-Tu ien tai tramBc 1:- m CB ha the va gi no m vi cha O;- cha O
c rut.Bc 2:- m dao cat trung the; - kiem tra xem bo ch th bang en
ton tai ien ap a tat cha khi dao cat trung the c m.Bc 3:- m khoa
dao tiep at pha trung the vi cha O va ong dao tiep at;- cha O c gi
lai.Bc 4:- tiep can panel cau ch trung the co the thc hien ( ngha
la co the thao cau ch trung the sau khi a ong dao tiep at pha trung
the). Cha S thng c at panel nay va c gi lai khi cac dao cach ly pha
trung ap ong- van cha S e khoa cac dao cat trung the ve pha v tr
m;- cha S c rut.Bc 5:- cha S cho phep thao bo thiet b khoa chung
cac au noi kieu cam pha trung the cua may bien ap hoac phan nap
chung bao ve cua cac au cc. Trong ca hai trng hp nay, s m ra cua
mot hoac nhieu au noi se gi cha S trang thai lien ong.
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f-Tu ien tai tramKet qua cua qua trnh mo ta tren la:Cac dao cach
ly trung the c khoa v tr m bang cha S. Cha S c gi cac au cc cua may
bien ap cho ti khi cac au nay con trang thai m. Cac dao tiep at pha
trung ap v tr ong nhng khong b khoa co ngha la co the m hoac ong.
Khi tien hanh cong tac bao tr, mot can khoa moc thng c dung e khoa
dao tiep at ve v tr ong, cha khoa c ky s giam sat cong tac gi.CB
pha ha ap c khoa v tr m bang cha O, cha nay c gi nh ong dao tiep at
trung ap.Nh o, may bien ap c cach ly mot cach an toan va c tiep
at.
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f-Tu ien tai tramCo the can ghi nhan rang au vao cua cac dao cat
( LBS ) co the van con ien trong suot qua trnh mo ta tren. Co 3 ly
do ve s ton tai ien au vao cac LBS nay nh sau:- cac au nay c at
trong cac ngan rieng khong the tiep can c trong cac thiet b ong cat
ac biet; - cac au tiep iem m cua cau dao co mot man chan c tiep at
nam gia chung;- phan vo boc cha cac dao c uc t vat lieu cach ien, c
lam ay bang kh SF6 va boc kn trong qua trnh van hanhTrong trng hp
chung, cac au vao cua cac dao (hoac may cat) se e h trong ngan
rieng va can phai co dao tiep at, dao nay c lien ong c kh vi dao
cach ly ng day. Hoac mot lan na, co the can (phu thuoc loai thiet b
ong cat) phai cach ly va khoa cap nguon trc khi ong dao tiep at tai
cho.
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III-BAO DNG
1-Nhan vien: Nhng ngi la nhan vien van hanh tien hanh bao dng
thiet b ien mot mnh va nhng ngi co chc danh cao nhat trong ca, nhom
ma thiet b ien o c giao cho ho phai co nhom an toan ien khong di IV
(cac thiet b ien co ien ap tren 1000V) va nhom III (cac thiet b ien
co ien ap en 1000V).Ch nhng ngi co nhom an toan ien khong di IV khi
can thiet mi c tien hanh kiem tra cac buong cua thiet b phan phoi
kn bang cach i vao pha trong rao chan vi ieu kien cac loi qua lai
khoang cach t san nha: en au nho ra thap nhat cua s cach ien khong
nho hn 2m; en cac phan dan ien khong c che chan khong nho hn 2,5m
khi ien ap en 10KV, - khong nho hn 2,75m khi ien ap en 35KV, -
khong nho hn 3,5m khi ien ap en 110KV va khong nho hn 4,2m khi ien
ap 150-220KV. Danh muc nhng buong nh vay c quy nh bang ch th cua
ngi chu trach nhiem ve ien.
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1-Nhan vien:
Khi khoang cach nho hn gia tr quy nh tren th ch cho phep i vao
ben trong rao chan khi co mat mot nhan vien th hai co nhom an toan
ien khong di III va phai tuan thu cac yeu cau Nhng ngi khong van
hanh thiet b ien c phep tien hanh kiem tra thiet b ien nay sau khi
co s cho phep cua ngi chu trach nhiem ve ien cua x nghiep, xng,
phan xng.
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1-Nhan vien: Ca cac phong at thiet b ien phai thng xuyen ong.oi
vi moi mot phong at thiet b ien phai co t nhat 2 bo cha khoa, trong
o mot bo la d phong. Bo cha khoa cua thiet b phan phoi khong c e
gan cac ca ra vao cua cac khoang, tu ien. Nhan vien van hanh phai
ghi vao so cac cha khoa. nhng may ien khong co nhan vien van hanh
thng xuyen th cha khoa phai e bang ieu khien ni trng ca. Phai ky
nhan khi giao cha khoa cho:a) nhng ngi c phep mot mnh kiem tra va
nhng ngi la nhan vien van hanh sa cha, trong o ca trng hp khong trc
ca, khi thc hien cac cong viec trong phong at thiet b ien.b) Ngi ch
huy cong viec, ngi phu trach cong viec hoac ngi theo doi trong thi
gian thc hien cac cong viec theo giay phep hoac ch th.Cha khoa c
giao khi lam thu tuc giay phep va hang ngay sau khi ket thuc cong
viec phai a tr lai v tr cu cung vi giay phep.Khi tien hanh cong
viec cac thiet b ien khong co nhan vien van hanh thng xuyen th cha
khoa phai a tr lai v tr cu khong cham hn mot ngay sau khi ket thuc
cong viec. Ch nhng ngi la nhan vien van hanh nhan va ban giao ca
qua ien thoai mi c phep dung cha khoa nhan vien e vao phong at
thiet b ien.
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2-Cac bien phap to chc:a) Lam thu tuc giay phep, ch th hoac danh
muc cong viec thc hien theo trnh t cong viec hang ngay; Giay phep
la nhiem vu tien hanh cong viec c lam thu tuc tren mau ac biet theo
quy nh va xac nh noi dung, v tr cong viec, thi gian bat au va ket
thuc, ieu kien tien hanh an toan cong viec, thanh phan oi va nhng
ngi chu trach nhiem ve an toan tien hanh cong viec v.vCh th la
nhiem vu thc hien cong viec, xac nh noi dung cong viec, ni tien
hanh, thi gian, cac bien phap an toan (khi can) va nhng ngi nhan
nhiem vu thc hien. Ch th co the c truyen trc tiep hoac nh cac phng
tien lien lac sau o ghi vao so van hanh. Cong viec hang ngay la s
tien hanh cac cong viec c giao theo danh muc soan thao theo phan
Thc hien cac cong viec theo ch th theo trnh t cong viec hang ngay
cua chng nay do nhan vien van hanh (van hanh sa cha) t mnh thc hien
trong mot ca.
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b) Cho phep tien hanh cong viec -Tien hanh kiem tra viec thc
hien cac bien phap ky thuat e chuan b v tr lam viec va ngi ch huy
cong viec phai ky vao giay phep dong quy nh trong trang sau (ch khi
cho phep lan au). Khong c thay oi cac bien phap chuan b v tr lam
viec a ghi trong giay phep. Kiem tra s phu hp cua thanh phan oi lam
viec va trnh o chuyen mon nhng ngi ghi trong giay phep. Phai nam ro
s o nguyen ly ve cap ien cua thiet b( ien ap c cat t au, tiep a c
at cho nao, nhng phan nao cua thiet b va cua cac au noi day con ien
ap va nhng ieu kien lam viec ac biet can tuan thu) va ranh gii v tr
lam viec -Phai hoan toan tin rang ien ap a c ngat: thiet b co ien
ap tren 35KV ch vao bo phan tiep a; nhng thiet b ien ap 35KV va
thap hn th nhng ni t v tr lam viec khong nhn thay c thiet b tiep a
dung tay cham vao cac phan dan ien sau khi a kiem tra s bo s ngat
ien ap bang ch th ien ap hoac sao.Khi thiet b tiep a c noi trc tiep
tai v tr lam viec th khong can cham tay vao cac phan dan ien;
-
c) Ban giao v tr lam viec cho ngi phu trach cong viec qua giay
phep co ch ky cua ngi cho phep va ngi phu trach cong viec . Mt bn
giy php phi c lu gi ch ngi ph trch cng vic, cn bn th hai c lu gi ch
nhn vin vn hnh trong tp ti liu cc giy php cn hiu lc.d) Giam sat
trong qua trnh lam viecNu do vic kt thc cng vic ca mt nhm khc hoc
do thay i mch thit b in m cc b phn ca chng nm bn ngoi v tr lm vic
theo giy php th c th c in p v do nghim cm li gn chng. Nghim cm mt
mnh ngi ph trch cng vic hoc cc thnh vin ca i khng c mt ngi ph trch
cng vic trong cc thit b phn phi h hoc kn ngoi tr mot so trng hp
-
+Ngh giai lao trong qua trnh lam viec, chuyen sang cho lam viec
khac, ket thuc cong viec: Khi cn ngh gii lao trong ngy lm vic (i n
tra, theo iu kin thc hin cng vic) i lm vic phi c a ra khi thit b
phn phi. Giy php phi c lu gi ti ch ngi thc hin cng vic (ngi theo
di). Cc bin bo, ro chn, thit b tip a phi c gi nguyn ti ch c. Khng
ai trong s thnh vin i lm vic c quyn vo lm vic trong thit b phn phi
sau khi ngh gii lao khi khng c mt ngi ph trch cng vic (ngi theo
di).
-
e)Kt thc cng vic, bn giao-tip nhn v tr lm vic. Kt thc giy php v
a trang thit b vo lm vic. Sau khi kt thc hon ton cng vic v tr lm
vic phi c thu dn, sp xp gn gng v c nghim thu bi ngi ch huy trch
nhim sau khi ngi ph trch cng vic a ton i ra khi khu vc lm vic, k vo
giy php v vic kt thc cng vic v bn giao giy php cho nhn vin vn hnh
hoc khi khng c nhn vin vn hnh th vo cp ti liu ng cc giy php cn hiu
lc.Cng tc kim tra cch in ca cc trang thit b sau khi sa cha ngay trc
khi m my phi c tin hnh, nu nh cn thit, trc khi tho b cc ro che chn
v cc bin bo phng nga tm thi ng thi ngay sau khi tho cc tip a tm
thi.Trang thit b c th c khi ng lm vic sau khi kt thc giy php.Nu nh
trn mi ni ngt cc cng vic c tin hnh theo mt s giy php th mi ni ch c
th c a vo lm vic sau khi kt thc tt c cc giy php.
-
3-CC BIN PHP K THUT M BO AN TON CHO CC CNG VIC THC HIN KHI CT IN
P+Chun b v tr lm vic khi tin hnh cc cng vic ct in p phi thc hin cc
bin php k thut :tin hnh ngt in nhng im cn thit v p dng cc bin php
ngn nga vic cp in p tr li v tr lm vic; trn cc c cu truyn ng iu khin
bng tay v trn cc kha iu khin t xa ca thit b chuyn mch phi treo cc
bin cm; kim tra s khng cn in p cc phn mang in v chng phi c tip a; t
tip a ;treo cc bin bo ngn nga v gii thch, che chn cc v tr lm vic v
cc phn mang in cn in p khi cn
-
+Thc hin cng tc ngt in+Sau khi ngt in phi to khong h thy c+Ngn
nga s ng in li nh:- cc dao cch ly, thit b ngn cch, thit b ct ti cc
c cu dn ng bng tay ti v tr ngt phi c kha li bng kha;Cc my bin p v
my bin dng lin quan n phn ca thit b in c tch ring ra thc hin cng
vic phi c ngt cng t hai pha in p n 1000V ngn nga s bin p ngc.-cc
thit b in c in p 6-10kV vi dao cch l mt trc ngn nga vic ng nhm chng
cho php treo dao cc m chp cao su chuyn dng.-. cc thit b in c in p
ti 1000V in p t mi pha trn cc phn mang in m ti tin hnh cng vic phi
c ngt bng cch ngt thit b chuyn mch c c cu dn 6ng bng tay cn khi
trong s c cc cu ch th tin hnh tho cc cu ch ny.
-
+Treo cc bin bo, che chn v tr lm vic.+ Treo cc bin bo: Khng ng.
C ngi lm vic, trn cc van ngn khng cho khng kh vo c cu truyn ng bng
kh nn phi treo bin Khng m. C ngi lm vic.+Che chn: Cc phn mang in
cha ngt in d b v tnh chm vo khi lm vic phi c che chn vi khong cch
ph hp v co ch: .Dng li. C in p.
-
Kim tra s khng c in p Cng tc kim tra s khng c in p phn ca thit b
in ngt in thc hin cc cng vic phi do ngi cho php lm vic tin hnh sau
khi treo cc bin cm.+B ch th in p: Phi s dng ch th in p do nh my ch
to m tin cy ca n trc khi s dng phi c kim tra bi cc dng c chuyn dng
cho mc ch ny hoc bng cch tin li gn cc phn mang in gn v c in p mt
cch r rng. cc thit b in in p trn 1000V phi s dng gng tay cch in lm
vic vi cc ch th in p. Cng tc kim tra s khng c in p cc trang thit b
phi c tin hnh tt c cc pha cn cc thit b ct in ln dao cch ly - phi
kim tra tt c su u vo v kp.Nu nh v tr lm vic mch in b t th s khng c
in p phi c kim tra cc phn mang in t hai pha ca ch b t. cc thit b in
in p 35kV v trn 35kV kim tra s khng c in p c th s dng so cch in v
chm mt vi ln so cch in ny vo cc phn mang in. Khi khng c tia la v
ting ku tch tch th l du hiu ca s khng c in p.Trong thit b phn phi h
in p ti 220kV ch cho php kim tra s khng c in p bng ch th in p hoc
so o trong iu kin thi tit kh ro. Khi thi tit m t vic kim tra s khng
c in p c thc hin bng cch theo di cn thn mch in trong t nhin. Trong
trng hp ny s khng c in p trn ng ra c khng nh li bi nhn vin vn hnh
hoc nhn vin iu .
-
Vic kim tra s khng c in p bng cch theo di mch in ti ch cho php
tin hnh trong iu kin thi tit m t cc phn trm bin p b v thit b phn
phi b bn ngoi tt c cc in p khi khng c thit b ch th in p chuyn dng c
cp s dng trong bt k iu kin thi tit no.Khi theo di mch in trong t
nhin s khng c in p cc u vo ca cp in v ng dy in trn khng c khng nh
bi nhn vin vn hnh.Trn cc ng dy in trn khng vic theo di mch in trong
t nhin bao gm kim tra hng v cc du hiu bn ngoi cng nh cc k hiu trn
ct in ph hp vi tn gi ca ng dy.+ Trn cc ct in bng g v b tng ca ng in
trn khng in p 6-20kV cng nh khi lm vic t cc thp lng xp khi kim tra
s khng c in p bng ch th in p trn c s nguyn l dng in dung phi m bo
nhy cm cn thit ca n. Khi phn lm vic ca ch th in p phi c tip a bng
dy dn c tit din khng nh hn 4mm2.+ cc thit b in in p ti 1000V phi
tin hnh kim tra s khng c in p gia cc pha cng nh gia tng pha vi thn
trang thit b c tip a hoc dy tip a (dy khng). Cho php s dng cc vn k
c kim tra s b. Nghim cm s dng cc n kim tra.
-
Tip a cho cc phn mang in. Cc yu cu chung. Vic tip a cho cc phn
mang in c thc hin nhm bo v ngi lao ng khi b tn thng do dng in gy ra
trong trng hp cp nhm in p ti v tr lm vic.. Vic t tip a cho cc phn
mang in phi tin hnh ngay sau khi kim tra s khng c in p. Cc tip a di
ng trc ht phi c ni vi t sau ni vi cc phn mang in sau khi kim tra s
khng c in p v c tho b theo trnh t ngc li: trc ht tho chng khi cc
phn mang in sau tho chng khi t.. Thao tc t v tho cc tip a di ng c
tin hnh khi phi s dng gng tay cch in v cc thit b in in p trn 1000V
s dng so cch in. Cc kp cc tip a di ng sau khi t phi c xit cht bng
so cch in ny hoc trc tip bng tay c s dng gng tay cch in.Nghim cm s
dng cc dy dn khng dng cho mc ch ny lm thit b tip a cng nh ni tip a
bng cch xon.
-
Tip a cc phn mang in cc thit b in ca cc phn trm v cc thit b phn
phi
Phi tip a cho cc phn mang in ca tt c cc pha, cc cc ca khu vc ngt
in thc hin cng vic ca thit b in ny t mi pha m t c th in p c truyn
ti ngoi tr cc thanh ci c ngt thc hin cng vic v trn cc thanh ci ny
ch t mt tip a l .Ti v tr lm vic phi t trc tip cc tip a b sung cho
cc phn mang in trong cc trng hp khi m cc phn mang in ny c th chu in
p cm ng (in th) c nguy c lm tn thng cho ngi lao ng hoc cc phn ny c
th b in p trn 42V (dng xoay chiu) hoc 110V (dng mt chiu) truyn ti t
mt ngun c nh (my hn, mng chiu sng v.v..). cc thit b in m do cu trc
ca chng vic t tip a gy nguy him hoc khng th thc hin c (v d: mt s t
phn phi, thit b phn phi b cc dng ring bit v.v..) khi chun b v tr lm
vic phi ap dng cc bin php an ton b sung nhm ngn nga vic cp in p nhm
ti v tr lm vic: cc c cu truyn ng v cc my mc ngt in phi kha li
v.v.
-
Tip a cho dy dn ti in trn khng
+ Cc ng dy ti in trn khng in p trn 1000V phi c tip a tt c cc
thit b phn phi v cc my ct phn an m ti ng dy c ngt in. Khi sa cha
tng pha ca ng dy ti in trn khng thit b phn phi nghim cm tip a cho
dy dn ca pha ngt in.. Khi thc hin cc cng vic trn cc dy dn ca ng dy
ti in trn khng khang ct ngang vi ng dy ti in trn khng khc c in p
phi t tip a ti ct in m ti tin hnh cng vic. Khi lm vic trn dy chng
st cch ly vi ct in hoc trn cc kt cu ca ct v nu cn thit phi li gn dy
ny khong cch di 1,0 mt th dy chng st ny phi c tip a.Tip a c t t ct
in v pha khong vt m ti dy chng st c cch in hoc ti chnh khong vt
.Trc khi lm t mch in ti v tr lm vic (tch cc dy dn, dy chng st, ngt
cc dao cch ly phn on) phi t tip t v hai pha ca ch t mch.
-
+ Ct:i vi cc ct in kim loi phi ni cc tip a di ng vi cc chi tit
ca chng, cn i vi cc ct b tng ct st v ct g c mng tip a th ni cc tip
a di ng vi cc mng ny sau khi kim tra nguyn vn ca chng.Trn cc ct b
tng ct st cho php ni cc tip a di ng vi ct hoc cc chi tit kim loi m
chng c ni bng kim loi vi ct ny. Trn cc ng dy ti in trn khng in p ti
1000V khi tin hnh cng vic t cc ct in hoc t cc thp lng xp khng c b
phn cch in phi tip a cho dy dn ca ng dy ang sa cha cng nh cho tt c
cc dy dn treo trn ct in ny trong c dy dn truyn thanh v iu khin t
xa. Trn ng dy ti in trn khng khi treo cc dy dn cc cao khc nhau phi
tin hnh t tip a t di ln trn bt u t dy dn di cng cn khi treo dy theo
mt phng ngang th t tip a bt u t dy dn gn nht.
-
BAO DNG ONG C IEN+ Dng ong c ien va tai c cau khi ong hoac khoa
ieu khien cua no phai treo bien canh bao va thiet b tiep a c rai
tren cap ien (noi hoac khong noi no vi ong c ien) hoac tren au noi
cua no thiet b phan phoi.Khi lam viec cac c cau ma khong lien quan
en viec cham vao cac phan quay hoac khi au noi a c thao ra th khong
can thiet phai tiep a cho cap nguon nuoi.Cac thao tac ong, m ong c
ien co ien ap tren 1000V bang thiet b khi ong truyen ong bang tay c
thc hien t san cach ien va phai s dung gang tay cach ien.
-
LAM VIEC CAC THIET B CHUYEN MACH (THIET B NGAT, MAY CAT PHU TAI,
THIET B CACH LY, CAU DAO NGAN MACH, CAU DAO CACH LY) VI C CAU DAN T
ONG VA IEU KHIEN T XA*.. Trc khi cho phep lam viec cac thiet b
chuyen mach ieu khien t xa phai:- ngat mach ien ong lc cua c cau
dan, mach dong van hanh va mach say;- ong va khoa cac van chan tren
ng ong dan kh vao thung cua thiet b ngat hoac vao c cau dan ong kh
nen va xa khong kh con lai trong o vao kh quyen, khi o cac nut
(van) xa phai v tr m;- cac vat nang e ong hoac cac lo xo ong phai a
ve v tr khong lam viec;- treo cac bien bao Khong ong. Co ngi lam
viec va Khong m. Co ngi lam viec tren cac van a c ong lai.
-
. BAO DNG THIET B PHAN PHOI HP BO Khi lam viec ben trong cac
khoang tu cua thiet b phan phoi phai khoa tam nap che cua khoang ma
cac phan ben trong con mang ien va treo bien Dng lai. Co ien ap.
Con trong khoang treo bien Lam viec tai ay.
LP RP V VN HNH CC DNG C O, THIT B BO V RLE, MCH TH CP, CC C CU T
NG HO, H THNG IU KHIN T XA V LIN LC. Lm vic vi ng h in.
m bo an ton cho cc cng vic tin hnh cc mch dng c o v c cu bo v
rle tt c cc cun dy th cp ca cc my bin dng o lng my bin p phi thng
xuyn c tip a. Khi cn thit phi lm t mch dng cc dng c o lng v rle th
mch ca vng th cp ca my bin dng phi c s b lm ngn mch cc kp chuyn s
dng cho mc ch ny.
-
NG DY TI IN TRN KHNGCc cng vic tin hnh m khng ct in p cc phn
mang in v gn chng Cc cng vic lin quan n vic tip xc trc tip vi dy dn
c in p ch c php tin hnh vi iu kin ngi lm vic phi cch ly vi t bng cc
thit b cch in: thp lng xp vi mt xch cch in, sn cch in, thang cch in
v.v Khi trc khi ngi lm vic tip xc vi dy dn th sn lm vic ca thit b
cch in phi c truyn in th ca dy bng cch dy dn c ni s b vi sn lm vic
phi c t chng ln trn dy dn nh so cch in. Cc cng vic trn chui s lm li
chui s, thay cc s cch in, thit b do th in ng trn cc c cu cch in hoc
thanh ngang thc hin ch c tin hnh vi iu kin s lng cc s cch in han ho
trong chui hoc gia dng c tho v dy dn khng nh hn gi tr trong bng
sau:
in p dy ti in trn khng, kV
S lng s cch in, chic
in p dy ti in trn khng, kV
S lng s cch in, chic
15
2
150
6
310
4
220
10
-
. Khi lm vic t sn ca c cu cch in c in th ca dy dn khong c chm vo
cc s v ph tng ca chui s c dy dn c in p cng nh chuyn hoc nhn dng c,
thit b cho nhng ngi khng trn sn lm vic ny. Khng c li gn dy thu li c
cch ly khi ct in khong cch nh hn 1 mt. Khi s dng dy trong mch nng
chy lm tan tuyt khong cch cho php li gn dy ni trn ty thuc vo in p
dng nng chy.Khng c lm vic trn cc ng dy in trn khng c in p khi sng
m, bo gi, ma, tuyt ri, vo ban m cng nh khi c gi mnh gy kh khn cho
cng vic trn ct in.+ Khi sa cha tng pha th trn dy dn ca pha ngt ti v
tr lm vic ch t mt tip a. Cho php lm vic trn dy dn ny khong cch khng
cch xa tip a qu 20 mt.
-
+Khi tin hnh o in tr tip a ca ct in phi s dng gng tay cch in ni
v tho ct tip a khi dy thu li hoc sau khi tip in s b cho dy thu li
ny.+ i vi ng dy ti in trn khng c in p trn 1000V nghim cm li gn dy
dn nm trn t trong phm vi 8 mt. Xung quanh ch dy dn nm trn t nh vy
phi t chc bo v ngn nga khng cho ngi v ng vt li gn+ Khng li gn qu 8
mt cc ct in b tng c in p ca ng dy in trn khng 6-35kV khi c cc du
hiu dng ngn mch chy t cc ct in ny xung t do hng cc s cch in, do dy
dn chm vo thn ct v.v(bay hi m t t, xut hin h quang in trn ct v ch
chn ct xung t v.v..). Gii phng ng dy in trn khng khng khi cy Trong
trng hp cy ln dy in khng c n gn cy trong phm vi 8 mt cho n khi ct
in p ca ng dy.
-
5-Cc thit b in ni d chy n
a-Vng d chy n:Cc v tr cch 5m theo chiu dc v ngang t cc thit b
lun c cht chy ,song qui trnh cng ngh c p dng ngn la m ,hay cc phn
ng kn khng c coi l c nguy c chy n.-Cc v tr c cha thit b c cht chy l
nguyn liu t khng c coi l c nguy c chy n
-
b-La chn thit b in:+La chn my in :trong vng chy n c th s dng cc
my in vi in p ti 10KV vi iu kin l v ca n c mc bo v thch ng vi 60ST
14254-80 (bng 1)-Khng kh thng gi my in khng c cha hi hay bi chy
.Vic thi khng kh sau khi lm vic trong chu trnh thng gi khp kn vo
vng chy n l khng c php.-Trong thit b in cho cc kh c in di ng trong
vng chy n cn thch ng vi v bo v mc Ip33(bo v khi vt rn ca kh c bng
lp dy>2,5mm v bo v khi ma) trong iu kin thc hin cc yu cu cng ngh
c bit cho sa cha thit b trong vng chy n. Cc my in c b phn thng c
tia la(nh vng contact) cn c b tr trn khong cch hn 1m t ch c cht chy
hoc cch ly bng mn hnh khng chy. + Cho php s dng ng c in vi v bo v c
mc thp hn vi Bng 1 trong cc iu kin sau:ng c cn t ngoi vng chy nc cu
truyn ng cn c thc thi nh trc t qua tng vi thit b trong n
-
+Thit b v kh c:trong cc vng chy n c th dung dng c ,t in v u ni
vi v bo v khng c thp hn bng 2 Trong vng chy n c th dng kh c in c lm
mt bi khng kh sch c p sut d v bng du (ngoi tr oxy v c cu nng) v my
ct ca mng chiu sng nn c b tr ngoi vng chy n. Nu trong vng chy n cn
c thit b t nng bng in th phn t nng cn c bo v khi s va chm vi cht
chy ,cn bn thn thit b c t trn b mt t vt liu khng chy.Trong bt k kho
c cht chy ,cc to nh lu tr v th vin khng c b tr cc thit b t nng.
-
+Cc c cu nng bng inDy dn ca c cu ny (cn trc.v.v..) trong vng chy
n loi -1 v -2 cn phi l cp dy mm vi li ng ,cch in cao su nm trong v
c bn vi mi trng xung quanh trong -2a v -3 cho php dng thang gp nhng
thang ny khng c php phn b trn cc v tr c cht chy n.+Thit b phn phi v
trm in:khng nn t thit b phn phi vo cc vng chy n .Trong tng hp ti cn
,mc bo v t in cn thch ng vi bng 2. Cho php t bin p trn b ngoi tri
vi bin p kh ,cng nh thit b t vi t c cht khng chy.Khi mc bo v v t
khng c nh hn Ip41(s 1 biu th l cn bo v khi nc ri thng vo v ). Ngoi
tr kho chy n v nh lu tr ,c th t bin th du trong dng trm kn vi cc iu
kin sau:Ca v l thng gi ca khung bin th v t c du khng c m ra vng d
chy nL trong tng v nn nh ch t cp cn c lp kn bi vt liu khng chy.Li
ra ca khung bin th vo vng d chy n c th c dn xut t ni t t in vi in p
nh hn 1000V.Khng cho php t li ra ca trm vo vng d chy n v khng cho
php vn chuyn bin th qua vng ny.Thit b in c du (bin th,t,my ct)c th
b tr trn khong cch nh hn 0,8m t tng ngoi to nh c vng chy n vi iu
kin l khong cch theo b ngang v ng t l ca trong tng ti thit b in
khng c nh hn 4m.
-
+n chiu sng:Trong vng chy n cn b tr thit b chiu sang vi mc bo v
theo Gost 17677-82 .Mc bo v khi s thm nhp nc c chn la ph thuc vo iu
kin mi trng .Cc n phi c bo v chng bi.Cc b n dy tc.cn c knh bo v
silicat dy v khng c cha t vt liu chy .Trong vng kho d chy n ,b n vi
n hunh quang.khng c c cha lm t vt liu chy. Dy in bn trong n vi n dy
tc v n phng in ti v tr kt ni vi dy bn ngoi cn phi c kh nng chu nhit
.Cc b n di ng trong vng d chy n phi c mc bo v khng nh hn Ip54 phn
knh ca b n cn c bo v bng li kim loi.
-
Dy dn:+Trong vng chy n cho php t cc loi dy dn ,Cp v dy cn c bc v
c v t cc vt liu khng lan truyn chy. S dng cp vi cch in Polyetylen l
khng c php. Qua vng d chy n ,cng nh trn khong cch nh hn 1m theo
chiu ngang v ng vng d chy n ,nghim cm t ng dy dn in v cp cc loi in
p (loi tr ng dy c lin quan ti dy chuyn cng ngh) .Khong cch t cp v
dy cch in t h trc tip theo kt cu nh,trn s,congxon.v.v.. ti v tr cha
cht chy n khng c nh hn 1m. Cc dy cch in song khng c bo v c li nhm
trong vng chy n phi c t trong ng v hp .Vic t dy khng cch in l b cm.
Vi ng ng c cht lng v kh chy trong vng -1,cho php t :dy cch in trong
ng tho ,dy khng cch in trong ng thp v hp,cp bc st t h. Khi ng dy
bng thp cn t trn khong cch khng t hn 0,5m khi ng c cht lng v kh chy
Vi cc ng dn in di ng cn dng cp mm vi li ng ,vi cch in cao su t
trong v c bn vi mi trng xung quanh. Cc hp ni cn c v c mc bo v khng
nh hn Ip4x (khng cho php cc vt rn thm nhp (nh hn 1mm) v bo v chng
nc thm nhp ). Phn hp lm bng kim loi cn c lp t cch in bn trong v c
sn chc chn. Trong vng chy n -1, -2, -2a cho php t thanh dn bng ng
hoc nhm vi v mc bo v khng thp hn Ip20 v t vng-1 v -2 ,cc thanh gp
cn cch in. Cc mi tip xc cn c hn cn nu vt th cn c g (ph tng).ngn chn
s t lng vt
-
Bng 1:Mc bo v ti thiu ca cc v my in
Dng thit b v iu kin lm vic
Mc bo v ca v
-1
-2
-2a
-3
Thit b tnh,vi phn c chu tia la in
Ip44
Ip54
Ip44
Ip44
Thit b tnh khng c phn chu tia la in
Ip44
Ip44
Ip44
Ip44
Thit b t trn c cu chuyn ng v trn cc thit b (cn tc,my nng)
Ip44
Ip54
Ip44
Ip44
_1192707518.unknown
-
Bng 2:
Dng v iu kin lm vic
Mc bo v ca v trong vng lm vic chy n
-1
-2
-2a
-3
Tnh hay trn c cu chuyn ng v trn cc thit b(cn trc,my nng.v.v)c
tia la in khi lm vic
Ip44
Ip54
Ip44
Ip44
Thit b tnh hay t trn c cu chuyn ng hoc trn cc thit b (cn trc,my
nng.v.v) khng c tia la in khi lm vic
Ip44
Ip44
Ip44
Ip44
T t thit b v dng c
Ip41
Ip54
Ip44
Ip44
Ip44
Hp u ni mch ng lc v nh th
Ip44
Ip44
Ip44
Ip44
_1192707518.unknown
