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Cach do dong ro ri dien bang dong ho vang nang
Cach Do
- Can kep dong hoac dong ho co thang mA.
- Kep vao day pha va doc gia tri.
- Toi da: 30mA cho nguoi, 300mA cho may.
Model ZOYI Phu Hop
ZT-303 (600A), ZT-301 (600A+Inrush), ZT-5BQ (600A) – kep dong kiem tra ro ri.
Cau Hoi Thuong Gap (FAQ)
Dong ro ri 30mA co nguy hiem khong?
30mA la han che an toan. Tren 30mA co the gay dien giat.
Bai Viet Lien Quan
Bao hanh 12 thang – Gia tot nhat
Cach Do Dong Ro Ri Dien Chi Tiet
Dong ro ri (leakage current) la dong nho chay qua chat long mach. Dong ro ri lon gay nguy hiem. 2 cach do: Cach 1: Truc tiep (dong ho noi vao mach). Chon mA, cat mach, noi dong ho vao giua. Doc gia tri. Cach 2: Khong tiep xuc (clamp meter). Vay kep quanh day. Doc gia tri. Cach 2 an toan hon.
Muc Do Dong Ro Ri
Nguyen Nhan Gay Dong Ro Ri
Do Dong Ro Ri Dien – Huong Dan An Toan
Dong ro ri (leakage current) la dong dien nho chay ra ngoai mach chinh, thoat qua chat long hoac loai bo. Dong ro ri lon gay: DIEN GIAT (nguy hiem cho nguoi), CHAY (dong ro ri sinh nhiet), HU HONG thiet bi. Kiem tra dinh ky giup phat hien som. Cach 1: Do truc tiep bang van nang (chon mA, cat mach, noi vao). Cach 2: Do gian tiep bang ampe kep.
Muc Nguyen Hiem
< 0.5mA: Binh thuong (tieu chuan IEC). 0.5-1mA: Can theo doi. 1-5mA: Co van de (can sua chua). > 5mA: NGUY HIEM (dien giat). > 10mA: Dien giat nguy hiem (co the gay tu vong). Luon su dung thiet bi RCD/ELCB de bao ve. Kiem tra dong ro ri dinh ky, dac biet o noi am uot (nha bep, phong tam, ngoai troi).
Dung Clamp Meter De Do An Toan
Cac loai dong ro ri dien
Dong ro ri dien (leakage current clamp) dung de do dong dien ro ri qua chat long bao ve hoac qua khoang khong khi giua cac day dan. Day la nguyen nhan chinh gay dien giat va chay no.
1. AC Leakage: Chi do dong ro ri xoay chieu. Pho bien kiem tra an toan dien gia dinh va cong nghiep. Gia 2-10 trieu.
2. True RMS: Do duoc ca AC va DC. Can cho kiem tra UPS, pin, he thong dien mot chieu. Gia 5-20 trieu.
3. Portable: Nhe, pin duoi, de mang theo. Cho ky thuat vien di cong tac. Gia 3-15 trieu.
4. Bench: Chinh xac cao, man hinh lon, ket noi may tinh. Cho phong thi nghiem. Gia tren 15 trieu.
Cach su dung an toan
Buoc 1: Kiem tra dong ro ri – dau do sach, pin du, chon che do AC/DC phu hop.
Buoc 2: Kep dong vao nguon dien vao thiet bi. Day dien xuyen qua giua ham kep, khong cham thanh kim loai.
Buoc 3: Doc gia tri, so sanh dinh muc. Gia tri binh thuong cho thiet bi dan dung duoi 1mA.
Buoc 4: Ghi nhan gia tri, thoi gian, dia diem. Theo doi tinh hong qua thoi gian.
Bao tri va kiem tra dinh ky dong ro ri dien
Ung dung cu the cua dong ro ri dien trong cong nghiep
Quy Trinh Kiem Tra Dong Ro Ri Toan Quoc
Theo QCVN 13:2012/BXD, he thong dien nha o can dam bao dong ro ri < 30mA. Cach kiem tra: 1) Dung RCD (residual current device). 2) Kiem tra RCD hoat dong dung khi co ro ri. 3) Do dong ro ri bang clamp meter. 4) Neu > 30mA, RCD phai cat nguon. ZOYI clamp ZT-QB9 (600A) phu hop cho kiem tra. Goi 0904 579 990.
Trong thuc te, viec do dac khong phai luc nao cung don gian nhu tren sach vo. Cac ky thuat vien dien co nhieu nam kinh nghiem thuong ap dung nhung meo sau de co ket qua chinh xac nhat: Thu nhat, luon kiem tra que do va day dan truoc khi bat dau cong viec. Day dan bi dut ben trong lop vo nhua la mot trong nhung nguyen nhan gay sai so va ton thoi gian nhat. Chi can mot cai nhin so qua va mot lan noi tat que do de kiem tra dong ho ve 0 la co the tranh duoc phien toan nay. Thu hai, khi do cac thong so dien o nhiet do khac nhau, can luu y rang nhiet do anh huong den ket qua do, dac biet la dien tro. Nhiet do cang cao, dien tro cang lon (doi voi da so vat lieu). Vi the, nen ghi lai nhiet do moi truong cung voi ket qua do de co co so so sanh chinh xac.
Thu ba, voi cac phep do tinh vi nhu do dien dung hoac dien cam (LCR), can cho dong ho on dinh it nhat 3-5 giay truoc khi doc gia tri boi cac linh kien nay co dac tinh nap/xa dien. Thu tu, thuong xuyen hieu chuan (calibrate) dong ho van nang bang cach do mot nguon chuan da biet truoc (vi du pin AA moi 1.5V) de kiem tra do chinh xac. Thu nam, khong bao gio de dong ho o thang do tro (Ω) khi cat giu – de o thang nay, neu vo tinh cam que do vao nguon dien se gay hong ngay lap tuc. Luon xoay nut ve thang ACV cao nhat hoac OFF sau khi dung xong. Cuoi cung, khi lam viec voi dien ap cao (>50V), luon su dung quy tac mot tay: mot tay cam que do, tay kia bo vao tui hoac de sau lung de tranh tao duong dan dien qua tim.
Thuong hieu ZOYI cung cap nhieu dong san pham phu hop cho cac muc dich su dung khac nhau, tu nguoi moi bat dau den ky thuat vien chuyen nghiep. Cac dong ho ZOYI deu duoc thiet ke voi giao dien truc quan, de su dung, phu hop voi nguoi dung Viet Nam. Mot so meo chung khi su dung dong ho ZOYI: Luon bat dau o thang do cao nhat roi giam dan de bao ve mach do va tranh gay soc. Su dung chuc nang HOLD de “dong bang” gia tri tren man hinh khi do o vi tri kho tiep can hoac thieu sang. Kiem tra dinh ky pin dong ho: pin yeu gay sai so dang ke va hien thi khong on dinh. Thuong xuyen ve sinh cac cong cam que do bang coi min hoac ban chai de loai bo oxy hoa, dam bao tiep xuc dien tot nhat. Dong ho ZOYI co tuoi tho pin tu 40-80 gio su dung tuy model, voi che do tu dong tat (auto power off) giup tiet kiem pin khi quen tat.
Khi mua dong ho ZOYI, nguoi dung duoc bao hanh chinh hang 12 thang va ho tro ky thuat mien phi. Tat ca san pham ZOYI deu co nhan CAT rating ro rang tren vo may va trong tai lieu di kem. Neu mua phai san pham khong co nhan CAT rating, do co the la hang gia hoac hang kem chat luong, khong dam bao an toan. ZOYI cung cap dich vu tu van chon model phu hop qua hotline 0904 579 990, giup khach hang chon dung thiet bi cho nhu cau su dung ma khong phai mua qua dat hoac thieu chuc nang. Voi chinh sach bao hanh ro rang va he thong phan phoi rong khap ca nuoc, ZOYI la thuong hieu dang tin cay cho nguoi dung do dien Viet Nam.
An toan dien la van de sinh ton, khong the xem nhe trong bat ky tinh huong nao. Theo thong ke cuc Boc hoi Lao dong, tai nan dien chiem ty le dang ke trong cac vu tai nan lao dong tai Viet Nam, va phan lon trong so do co the tranh duoc neu tuan thu cac quy tac an toan co ban. Khi su dung bat ky thiet bi do dien nao, tu mot chiec dong ho van nang don gian den thiet bi chuyen dung phuc tap, nguoi dung phai hieu ro gioi han cua thiet bi va moi truong lam viec.
Cac quy tac vang khong the quen: Khong bao gio do dien tro khi mach dang co dien. Khong bao gio do dong dien khi que do cam o cong do dien ap. Luon kiem tra CAT rating cua dong ho va que do xem co phu hop voi cap dien ap can do khong. Khong su dung dong ho bi vo vo hoac queens do bi troc vo cach dien. That chat cac moi noi truoc khi do de tranh tiep xuc dien kem gay hien tuong phong dien (arcing). Mang trang bi bao ho lao dong phu hop: gang tay cach dien, giay each dien, kinh bao ve. Dat thiet bi do tren be mat kho, ko dan dien. Neu co the, nen co nguoi thu hai ben canh de ho tro khi gap su co. Cuoi cung, ngat nguon va kiem tra bang thang ACV truoc khi cham tay vao mach dien, ngay ca khi ban nghi rang mach da duoc ngat dien.
Viec nam vung ky nang do dac khong chi giup ban hoan thanh cong viec nhanh hon ma con giup phat hien som cac van de tien an cua he thong dien. Mot ky thuat vien gioi thuong xuyen kiem tra dinh ky cac thong so dien cua he thong, ghi chep lai so lieu va so sanh theo thoi gian de nhan biet xu huong suy giam. Vi du, dien tro noi dat tang dan theo thang nam cho thay he thong tiep dat dang bi an mon. Tuong tu, dong dien ro tang dan cho thay lop cach dien dang bi gia hoa. Phat hien som nhung van de nay giup tranh duoc cac su co dien nghiem trong, gay mat dien hoac thiet hai tai san.
Tai lieu ky thuat ZOYI bang tieng Viet cung cap huong dan chi tiet cho tung buoc do dac, kem theo hinh anh minh hoa va cac luu y an toan can thiet. Nguoi dung co the tai ve mien phi tu website zoyi.vn hoac xem video huong dan tren kenh YouTube chinh thuc. Dieu nay giup rut ngan thoi gian hoc tap va tang do chinh xac khi thao cac phep do thuc te.
Viec su dung dong ho van nang dung cach khong chi giup ban co ket qua do chinh xac ma con keo dai tuoi tho cho thiet bi. Mot trong nhung loi thuong gap nhat la de dong ho o thang do tro (Ω) khi cat giu. Khi o thang nay, neu vo tinh cam que do vao nguon dien, dong ho se bi hong ghep do dong dien tu nguon se chay qua mach do va gay chay cac linh kien ben trong. Vi the, sau khi su dung, luon xoay nut chuc nang ve vi tri OFF hoac thang ACV (dien ap xoay chieu) cao nhat de bao ve dong ho. Viec don gian nay co the keo dai tuoi tho cua dong ho len gap 2-3 lan so voi nguoi dung khong de y.
Khi bao quan dong ho van nang, can de noi kho thong, tranh anh nang truc tiep va nhiet do cao. Neu khong su dung trong thoi gian dai (tren 1 thang), nen lay pin ra khoi may de tranh pin chay an mon cac tiep diem ben trong. Cac cong cam que do thuong bi oxy hoa theo thoi gian, can duoc ve sinh dinh ky bang dung dich chuyen dung hoac coi min de dam bao tiep xuc dien tot. Mot chiec dong ho duoc bao quan tot co the su dung trong nhieu nam ma van dam bao do chinh xac.
