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delay timer v ng dng trong iu khin chiu sng cng cng

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Cc c tnh ca delay timer v ng dng trong iu khin chiu sng cng cng cho cc cng trnh nh cao tng.

1. Gii thiu v delay timer (r le thi gian tr):

- M t: cung cp tt c cc loi iu khin t ng nh: nh sng, thng gi, ti nc, my, si m, ca t ng v to tn hiu m thanh hnh nh theo chu k...- Cc tn hiu u vo c thng qua cc thit b chuyn mch khc nhau(nt bm, cht chuyn i, timeclock vv) v thi gian c s dng kim sot ng dng...

-Thngs k thutDi in p:12 & 24 - 48V DC12 & 24 n 230V ACiu chnh c: thi gian tr hon t 0.1s n 10 gi.LED ch bo- Cc loi c tnh ca delay timer:

+ Delay on: sau khi c tn hiu u vo mt thi gian nht nh r le s ng tip im v s m tip im khi ht tn hiu u vo. Delay on c ng dng cho cc trng hp khng ch cc thit b in hot ng theo th t hoc trnh khi ng cc my in c cng sut v dng khi ng ln cng 1 lc (s gy ra qu ti)...

+ Delay off: Khi c tn hiu u vo, tip im ca rle s ng v sau 1 khong thi gian T (t khi kt thc tn hiu u vo) rle mi m. Delay off ng dng cho cc trng hp cn t ng tc thit b sau 1 khong thi gian tr T. Nh vy s trnh c trng hp ta bt thit b in ln nhng qun khng tc gy lng ph in.

+ Adjustable time ON (iu chnh thi gian ng): khi c tn hiu u vo r le s t ng tt sau 1 khong thi gian T ngay c khi vn duy tr tn hiu u vo. Adjustable time ON dng trong cc trng hp khng ch thi gian hot ng ca thit b in no . Trong cc nh my, x nghip cc quy trnh vn hnh ca cc giai on sn xut c thi gian nht nh, vic p dng Adjustable time ON l rt hp l...

+ Timer: khi c tn hiu u vo, rle s t ng tt sau 1 khong thi gian T bt k tn hiu u vo cn duy tr hay ngt. Timer cng tng t nh Adjustable time ON ch khc l r le s tt m khng ph thuc vo thi gian duy tr tn hiu u vo.

+ Symmetrical flasher (lp i lp li theo chu k): Khi c tn hiu u vo th r le s t ng ng - m theo khong thi gian T n khi ta ngt tn hiu u vo. ng dng trong cc trng hp n bo tn hiu, nhp nhy...

2. ng dng Delay off vo iu khin chiu sng khu vc cng cng cho cc cng trnh nh cao tng.

+ i vi cc khu vc cng cng nh hnh lang chung c, cu thang b l nhng v tr m mi ngi u c quyn s dng chung v phi c s dng 24/24h. Chnh v vy bi ton t ra y l lm th no kim sot c cc n chiu sng khu vc ny va tit kim, va tin dng.

+ Hin nay hu ht cc cng trnh Vit nam u cha c gii php hp l cho cc khu vc cng cng ny. Cc n khu vc ny hin nay hoc l bt 24/24, hoc c cng tc ti v tr hnh lng, cu thang mi ngi t iu khin hoc Ban qun l ta nh t bt tc theo thi gian no hoc s dng cm bin chuyn ng.... Nh vy nu bt 24/24 s gy lng ph in rt ln, nu t cng tc ti ch th ngi bt nhng thng s chng c ai tc, nu ban qun l ta nh bt tt th ban m mui i li chc phi dng n Pin, cn nu s dng cm bin chuyn ng th rt tn km v hn na cc n s lin tc bt, tt v khu hnh lang lun c ngi qua li gy ra rt nhanh hng n...

+ Gii php ti u gii quyt tt c cc vn trn l dng Delay off kt hp vi cm bin chuyn ng ti mt vi v tr. Nh vy va tin dng, va tit kim in m chi ph lp t cng khng cao. Chi tit xem bi s cp in snh, thangti y.

- See more at: http://htcodien.com/index.php/kien-thuc-tong-hop-me/he-thong-dien/203-delay-timer-va-ung-dung-trong-dieu-khien-chieu-sang-cong-cong#sthash.qYE644ID.dpuf

ng dng relay 24 gi

Nu bn c mt trong cc yu cu sau y th c lrelay 24 gi(timer switch) l ci bn cn:

6 gi ti th cho m h thng chiu sng, 6 gi sng t ng tt.

C mi 2 gi sng th cho my bm t bm nc ln bn (v lc ny chc chn c nc), khi bm y th t tt my bm.

C 9 gi sng th m my bm h thng ti nc cho vn, ti 15 pht th dng 45 pht, qu trnh c lp li n 15h th khng cho php bm na.

Bn c mt h thng 2 my bm lun phin, mi bm hot ng 1 ting th dng, my cn li hot ng thay th.

Bi vit ny s hng dn bn s dngrelay 24 gi thc hin nhng cng vic trn.C nhiu hng sn xut relay 24 gi. th trng Vit nam c cc loi ca JYE / Camsco (i loan), Panasonic. Bi ny s hng dn s dng relay TB35N ca JYE / Camsco, cc relay khc cng s dng tng t.

Relay 24 gi thng c 2 loi :

Loi khng c pin d tr (s chy sai gi khi cp in)

Loi c pin d tr (vn duy tr c hot ng ca ng h khi cp in)

Hnh nh relay TB35N nh sau :

Thi gian hin ti xem kim hoc xem vng s 24 gi. Lu mc gi hin ti trn vng 24 gi chnh l v tr tc ng.

Ch tc ng l 1 trong 3 ch sau :

OFF : tt cng tc ng ra ti.

ON : M cng tc ng ra ti

Auto : Cng tc ng ra ti c iu khin bi cc cht chnh tc ng. V tr cc cht quyt nh trng thi contact.

1. ng dng tt m n: s nh sau :

Chnh cc cht tc ng, cp ngun vo mch ta s c mch iu khin tt m n theo mnh. Nu ti s dng c dng ln ta s dng thm relay hoc contactor... Cc s ny s c b sung sau.

2. ng dng tt m my bm nc ln bn:

Bn s dng phao bm kt hp vi relay 24 gi. Lu l relay 24 gi phi c cp ngun lin tc. Nu s dng my bm c cng sut nh hn 1HP (dng in max 4.5A), ta s dng trc tip tip im carelay 24 githeo s sau:

Nu s dng my bm c cng sut ln hn 1HP, ta s dng relay hoc contactor m rng kh nng ti dng in. S c dng nh sau:

Vui lng xem thm

ng dng relay bo v mt pha, o pha MX100

Ting Anh chuyn ngnh dng ch hin tng mt pha : phase loss, phase failure, phase missing.

Ting anh chuyn ngnh dng ch hin tng o pha : phase sequence, phase reversal.

Chuyn mt pha trong h thng in 3 pha gy ra nhng hu qu ln khng cn l g vi dn k thut in, nht l dn bo tr in trong cc xng c cc ng c 3 pha. Ti khng mun ni v cc h hng m n gy ra cho bn, cho thit b ca bn. Mt khi bn tm n v c bi vit ny c ngha l bn hoc trong tng lai gn s i mt vi n.

Bn c th t lp mch bo v mt pha bng 2,3 relay king m theo bn l rt hiu qu v r tin. Ti ch mun ni vi bn rng : c nhng ngi phi th nhn mch hot ng km hiu qu trong h thng in cng nghip.

Trong phm vi bi vit ny ti s gii thiu cc ng dng ca relay bo v mt pha, o phaMX100AcaMikro(Malaysia) vo cc trng hp c th.

Th nht : Bo v mt pha v o pha trong h thng in.

Bo v mt pha dng ch yu cho cc ti 3 pha m ti nu mt 1 trong 3 pha th s gy ra s hot ng sai v d ng c ba pha khi mt 1 pha th d b chy, chnh lu 3 pha nu mt 1 pha th in p DC ng ra c th b thay i vv.

Bo v o pha s dng trong trng hp ng c 3 pha truyn ng trong cc h thng m chiu quay c n nh v s gy ra h hng nu nhn nt chy thun m ng c li chy ngc. Vic o pha ch c th xy ra khi tin hnh sa cha, thay th my bin p hoc ng dy.

Th 2 : Relay bo v mt pha, o phaMikroMX100A.

Relay Mikro MX100 c thit k s dng cho cm 11 chn. Hnh nh relay v s chn nh sau :

trng thi khng cp in th tip im 1-3 h, tip im 1-4 ng.

Nu c cp ngun 3 pha 3 dy hoc 3 pha 4 dy ng th t pha th tip im 1-3 ng li, tip im 1-4 m ra. n bo cun dy sng v n bo tip im sng th hin trng thi li in pha v ng th t pha. y l trng thi thng trc khi ta s dng relay ny.

Nu mt t nht 1pha th s c nhng hin tng sau xy ra : n bo tip im tt hoc n bo cun dy v n bo tip im u tt; tip im 1-3 h, tip im 1-4 ng li.

Nu c hin tng o pha xy ra th n bo tip im s tt ng thi tip im 1-3 s m ra, 1-4 s ng li.

Th 3 : ng dngMikroMX100 trong mch s dng contactor.

Ly v d mch khi ng ng c. Mch khng s dng relay bo v mt pha, o pha c s nh sau :

S c s dng relay bo v mt pha, o pha MikroMX100Anh sau :

So snh 2 s ta s thy ngay c nhng vic cn lm khi mun gn thm relay bo v mt pha o pha cho mch cha c bo v mt pha o pha.

Th 4 : ng dng Mikro MX100 trong mch s dng MCCB.

i vi mch in c cp ngun bng MCCB, ta mun khi c hin tng mt pha, MCCB s t ng nhy (tc ng). Ta cng bit r MCCB c ch to ch tc ng khi c hin tng ngn mch hoc qu ti. Tuy vy ta vn c th buc MCCB tc ng bng cch s dng ph kin "Shunt Trip". Shunttrip l ph kin c lp vo MCCB gip ta buc MCCB nhy bng cch a in vo cun dy ca Shunt trip.

cp in vo Shunttrip khi c hin tng mt pha, o pha, cn gn dng tip im thng ng 1-4. Tuy nhin ta cn lu l khi cha c cp ngun th tip im ny vn ang ng. Do vy, nu s dng ngun di MCCB cp vo MikroMX100A, rt c th khi ta va ng MCCB th shunttrip c cp ngun lm MCCB tc ng. trnh tnh trng ny ta c th s dng dng ngun trn MCCB cp cho MX 100 theo s sau :

S trn c nhc im l gi s tip im ca MCCB h hng, lc ny ngun cp ra ti mt pha nhng MikroMX100Akhng pht hin c.

Ngun cp cho Mikro MX100 vn c th ly di MCCB khc phc s c trn. Tuy nhin cn khc phc tnh trng MCCB s tc ng ngay khi ng MCCB. Ta c th dng thm 1 relay thi gian khng ch khng cho Shunttrip tc ng khi ta thao tc ng ngun (dng tip im thng m ng chm).

Th 5 : ng dngMikroMX100 trong mch s dng ACB.

ACB (Air Circuit Breaker : my ct khng kh) thng c s dng trong cc xng ln. ACB linh ng hn MCCB nh cc ph kin gip ta c th thao tc ng v ct ACB bng tn hiu in. Ngi ta thng s dng kt hp 2 hoc nhiu hn 2 ACB to thnh ccb chuyn ngun t ng (ATS : Automatich Transfer Switch).

Vic ng dng Mikro MX100 trong mch s dng ACB c bn cng tng t nh vi MCCB. im cn lu l khi MX100 pht hin mt pha, o pha. Ngoi vic cp ngun cho SHT tc ng ACB ta cn phi ngn khng cho b iu khin ng li ACB trnh tnh trng ng ct lp li nhiu ln nh hng n tui th ACB.

Lu chung cho c 2 trng hp s dng MikroMX100Acho mch s dng MCCB v ACB chnh l trng hp mt ng pha ly in p cp cho shunttrip. Chng ta c th phng trng hp ny bng cch trang b ngun d phng hoc lp mch dng ngun cp cho shunt trip c 3 pha theo th t u tin (Nu c pha R th dng R, nu mt pha R th dng pha S, nu mt pha R v S th dng pha T).

Nu cn tng s tip im ca MikroMX100A phc v cho cc mch iu khin, ta c th dng thm Relay trung gian.

ng dng relay bo v mt pha, thiu p, qu p MX200A

Gii thiu v hin tng thiu p, qu p :

Ting Anh chuyn ngnh dng ch hin tng mt pha : phase loss, phase failure, phase missing.

Ting anh chuyn ngnh dng ch hin tng thiu p (st p, thp p) : under voltage.

Ting anh chuyn ngnh dng ch hin tng qu p : over voltage.

Sau s c mt pha, th bo tr ng c thng nhc n s c thiu p, c bit l th qun ng c nhng vng c in p thng b thiu. Mt s th cha kinh nghim thng x l sai s c thiu p i vi ng c khng ng b. H l lun th ny : Theo nh lut Ohm, dng in t l thun vi in p do vy khi c hin tng st p th dng in qua ng c s gim nn hin tng pht nhit v chy ng c kh c th xy ra. Do vy khi gp ng c chy, h x l bng cch qun tng thm 1 s vng dy. iu ny lm s c thm nghim trng, ng c mi qun chy nhanh hn ng c c.

hiu r hn hin tng ny ta phn tch hin tng da vo ng c tnh c, ng c tnh dng in ca ng c khng ng b. Chng ta quan st ng c tnh c, c tnh dng in ca ng c khng ng b in p nh mc trong hnh sau:

T hnh v ta rt ra nhng kt lun sau :

Dng in m my (khi ng) rt ln nhng moment m my nh.

Trong qu trnh m my, moment tng dn cn dng in gim dn

Trong qu trnh lm vic, moment tng th dng in tng v ngc li moment gim th dng in gim.

n gin ha, ta ch phn tch on lm vic ca c tnh, khng phn tch qu trnh khi ng. Ti dng phn tch l mt ti khng i. ng vi ti nh mc, ta xc nh c h s trt nh mc (sdm). T h s trt nh mc ta xc nh c dng in nh mc ca ng c nh trn hnh c tnh.

Ta xt thm trng hp in p stator ca ng c gim xung 1 t, lc ny ng c tnh c v c tnh dng in thay i sang ng s 2 nh trong hnh v:

T hnh v, ta thy khi in p gim, ng c s lm vic ng c tnh M2, I2. lc ny trt s tng, dng in tng nhiu. y chnh l nguyn nhn lm ch ng c chy.

Vy cn khi in p tng? Cc thit b in ni chung s gim tui th hoc h hng v qu in p nh mc.

c bit t in s gim tui th rt nhanh nu qu in p. Ci ny c l khng cn phi gii thch thm nhiu.

By gi ni v phn chnh : ng dng ca relay bo v mt pha, thiu p, qu pMX200AcaMikro(Malaysia).

Th nht : Relay bo v mt pha, thiu p, qu pMX200A.

RelayMX200Aca Mikro (Malaysia) c thit k s dng cho cm 11 chn ging nhMikroMX100. Relay ny s dng c cho h thng 3 pha 380V hoc 1 pha 220V. Hnh nh relay v s u ca relay ny nh sau :

trng thi khng cp in th tip im 1-3 h, tip im 1-4 ng.

Nu c cp ngun 3 pha 4 dy hoc hoc 1 pha ng nh s , h thng khng mt pha, khng qu p, khng thiu p th tip im 1-3 ng li, tip im 1-4 m ra. n bo cun dy sng v n bo tip im sng th hin trng thi li in pha v ng in p. y l trng thi thng trc khi ta s dng relay ny.

Nu c hin tng mt pha, thiu p, qu p ti cc pha th tip im 1-3 h, tip im 1-4 ng li.

Bo v thiu p chnh c t 76% n 98%. Bo v qu p chnh c t 100% n 112%

Th hai : ng dng relay bo v mt pha, thiu p, qu pMX200Aca Mikro.

ng dng relay bo v mt pha, thiu p, qu p MX200A (Mikro, Malaysia) trong h thng in tng t nhrelay mt pha o phaMX100.

Trong cc h thng i hi bo v mt pha, o pha, thiu p, qu p th ta kt hp c 2 relay ny. Nu dng vi mch s dng contactor th 2 tip im (1-3) ca MX100 v MX200A c mc ni tip. Nu dng mch s dng MCCB hoc ACB. th 2 tip im (1-4) ca MX100 v MX200A mc song song.