1756-L75 AB

時間：2018-03-14作者：廈門仲鑫達(dá)科技有限公司瀏覽：34

接地是提高電子設(shè)備電磁兼容性（EMC）的有效手段之一。正確的接地，既能抑制電磁干擾的影響，又能抑制設(shè)備向外發(fā)出干擾；而錯誤的接地，反而會引入嚴(yán)重的干擾信號，使PLC系統(tǒng)將無法正常工作。

PLC控制系統(tǒng)的地線包括系統(tǒng)地、屏蔽地、交流地和保護(hù)地等。接地系統(tǒng)混亂對PLC系統(tǒng)的干擾主要是各個接地點電位分布不均，不同接地點間存在地電位差，引起地環(huán)路電流，影響系統(tǒng)正常工作。例如電纜屏蔽層必須一點接地，如果電纜屏蔽層兩端A、B都接地，就存在地電位差，有電流流過屏蔽層，當(dāng)發(fā)生異常狀態(tài)如雷擊時，地線電流將較大。

此外，屏蔽層、接地線和大地有可能構(gòu)成閉合環(huán)路，在變化磁場的作用下，屏蔽層內(nèi)有會出現(xiàn)感應(yīng)電流，通過屏蔽層與芯線之間的耦合，干擾信號回路。若系統(tǒng)地與其它接地處理混亂，所產(chǎn)生的地環(huán)流就可能在地線上產(chǎn)生不等電位分布，影響PLC內(nèi)邏輯電路和模擬電路的正常工作。PLC工作的邏輯電壓干擾容限較低，邏輯地電位的分布干擾容易影響PLC的邏輯運(yùn)算和數(shù)據(jù)存貯，造成數(shù)據(jù)混亂、程序跑飛或死機(jī)。模擬地電位的分布將導(dǎo)致測量精度下降，引起對信號測控的嚴(yán)重失真和誤動作。



ASHCROFT 20W1005 H 01B VAC 30-0IN-HG 2 IN 1/8 IN NPT PRESSURE GAUGE D554853


ASHCROFT 35-1009-AW-02L-?600 DURALIFE 0-600PSI 1/4 IN NPT GAUGE D554845


FOXBORO SUPPLY PRESSURE GAUGE DO NOT EXCEED 200KPA/30PSI 1/4IN NPT D541248


FOXBORO 0-30PSI 1/8 IN NPT SUPPLY PRESSURE GAUGE D541250


USG 656615AN3CD3A00 AMETEK PRESSURE GAUGE 0-600PSI 1/4IN NPT D585422


ASHCROFT 20W1005 H 02L 0-100PSI 2 IN 1/4 IN NPT PRESSURE GAUGE D559422


MARSH J1846 BELLOFRAM 0-60PSI 2 IN 1/8 IN NPT PRESSURE GAUGE D559423


ASHCROFT 20W1005 H 01B 0-100PSI 2 IN 1/8 IN NPT PRESSURE GAUGE D559419


WEKSLER BM2-39 -40-0-160F -40-0-70C THERMOMETER 1/2 IN NPT 6IN STEM D545328


TREND CR5009-X-A BI-METAL THERMOMETER 150-750F D568820


WINTERS 0-3000PSI 4 IN 3/4 IN NPT PRESSURE GAUGE D568748


ASHCROFT 30-EI-60-R-060-?0/250F THERMOMETER 0-250F 3 IN 1/2 IN NPT D555300


USG 56-81-5 0-200PSI 4 IN 1/2 IN NPT PRESSURE GAUGE D569507


SPRIANO 10/2000 5-1/2IN STEM THERMOMETER 0-60C 1/2 IN NPT D537230


DIXON GL340 PRESSURE GAUGE 0-200PSI 2-1/2 IN 1/4 IN NPT D581693


ASHCROFT 25W1005 H 02L PRESSURE GAUGE 0-30IN-HG 2-1/2 IN 1/4 IN NPT D581700


WIKA 9678000 NPT 2-1/2IN 1/4IN PRESSURE GAUGE D581689


AMETEK USG 505A PRESSURE GAUGE 2-1/2IN 1/4IN NPT D581695


WORKSMART WS-PE-GAGE-44 PRESSURE GAUGE 2-1/2IN 1/4IN NPT D581573


ASHCROFT 15W1001TH 01B XUC160 0-160PSI 1-1/2IN 1/8IN NPT PRESSURE GAUGE D588744


ASHCROFT 20W1005-H-02L-1?00 1/4"NPT 0-100PSI 2IN PRESSURE GAUGE D588322


AMETEK 163930 P500K 0-30PSI 2IN 1/8"NPT PRESSURE GAUGE D588326


AMETEK 005495A USG C505A -30-0IN-HG 0-30PSI 1/4IN NPT PRESSURE GAUGE D546398


ASHCROFT 30-0IN-HG 0-30PSI 1/4 IN NPT PRESSURE GAUGE D537717


ASHCROFT 30-0IN-HG 0-15PSI 1/2IN NPT PRESSURE GAUGE D537719


GORMAN RUPP 21-1348-02 LIQUID FILLED PRESSURE GAUGE 0-160PSI 1/4IN NPT D582067


FISHER 0-160PSI 1/4 IN NPT PRESSURE GAUGE D542042


TRERICE 800B1501BA100 0-60PSI 1-1/2 IN 1/8 IN NPT PRESSURE GAUGE D542034


TRERICE 800B D39112 0-60PSI 1-1/2 IN 1/8 IN NPT PRESSURE GAUGE D542037


ASHCROFT 35-1009-AW-02L-?600-XLJLL DURALIFE 0-600PSI 3-1/2 IN GAUGE D542127


ASHCROFT DURALIFE PRESSURE GAUGE 0-60PSI 1/4 IN NPT D578579


ASHCROFT 25W1005 H 02B DRESSER 0-60PSI 2-1/2 IN 1/4 IN PRESSURE GAUGE D545528


WINTERS PFQ904 PRESSURE GAUGE 0-100PSI 2-1/2IN 1/4IN NPT D592998


MOORE 3-1/2IN 1/4IN NPT 0-14PSI PRESSURE GAUGE D593009


ASHCROFT 20W1005-H-02L-2?00 PRESSURE GAUGE 0-200PSI 2IN 1/4IN NPT D585686


MARSH J4676 0-2000PSI 2-1/2 IN 1/4 IN NPT PRESSURE GAUGE D537534


NISSHIN R407C PRESSURE GAUGE 0-4MPA JIC-4 D578721


NISSHIN R407C COMPOUND PRESSURE GAUGE -0.1-0-1.6MPA JIC-4 D578722


ASHCROFT 35-1009-AW-02B-?3-15 GAUGE 3-15PSI 0-** 3-1/2IN 1/4IN NPT D585675


ASHCROFT TYPE 1008 0-1000PSI 4 IN 1/4 IN NPT PRESSURE GAUGE D537579


WEKSLER BY12YPS4CW PRESSURE GAUGE 0-2000PSI 2-1/2IN 1/4IN NPT D585682


ASHCROFT 20W1005-H-02B-1?00 PRESSURE GAUGE 0-100PSI 2IN 1/4IN NPT D585691


ASHCROFT 20W1005-H-02L-1?60 PRESSURE GAUGE 0-160PSI 2IN 1/4IN NPT D585766


ASHCROFT 20W1005-H-02L-3?0 PRESSURE GAUGE 0-30PSI 2IN 1/4IN NPT D585769


AMETEK USG 163272 P500K PRESSURE GAUGE 0-60PSI 2IN 1/4IN NPT D585772


AMETEK P844U 0-100PSI PRESSURE GAUGE 2-1/2 IN 1/8 IN NPT D578710


ASHCROFT TYPE 1008 0-160PSI 100MM 1/4 IN NPT PRESSURE GAUGE D578688


MEYLAN 20-200FPM 5/8 IN NPT GAUGE D546438


WIKA 8945217 432.12.100 SEALGAUGE 0-250PSI 3/4 IN NPT PRESSURE GAUGE D559450








ASHCROFT 20W1005 H 01B VAC 30-0IN-HG 2 IN 1/8 IN NPT PRESSURE GAUGE D554853


ASHCROFT 35-1009-AW-02L-?600 DURALIFE 0-600PSI 1/4 IN NPT GAUGE D554845


FOXBORO SUPPLY PRESSURE GAUGE DO NOT EXCEED 200KPA/30PSI 1/4IN NPT D541248


FOXBORO 0-30PSI 1/8 IN NPT SUPPLY PRESSURE GAUGE D541250


USG 656615AN3CD3A00 AMETEK PRESSURE GAUGE 0-600PSI 1/4IN NPT D585422


ASHCROFT 20W1005 H 02L 0-100PSI 2 IN 1/4 IN NPT PRESSURE GAUGE D559422


MARSH J1846 BELLOFRAM 0-60PSI 2 IN 1/8 IN NPT PRESSURE GAUGE D559423


ASHCROFT 20W1005 H 01B 0-100PSI 2 IN 1/8 IN NPT PRESSURE GAUGE D559419


WEKSLER BM2-39 -40-0-160F -40-0-70C THERMOMETER 1/2 IN NPT 6IN STEM D545328


TREND CR5009-X-A BI-METAL THERMOMETER 150-750F D568820


WINTERS 0-3000PSI 4 IN 3/4 IN NPT PRESSURE GAUGE D568748


ASHCROFT 30-EI-60-R-060-?0/250F THERMOMETER 0-250F 3 IN 1/2 IN NPT D555300


USG 56-81-5 0-200PSI 4 IN 1/2 IN NPT PRESSURE GAUGE D569507


SPRIANO 10/2000 5-1/2IN STEM THERMOMETER 0-60C 1/2 IN NPT D537230


DIXON GL340 PRESSURE GAUGE 0-200PSI 2-1/2 IN 1/4 IN NPT D581693


ASHCROFT 25W1005 H 02L PRESSURE GAUGE 0-30IN-HG 2-1/2 IN 1/4 IN NPT D581700


WIKA 9678000 NPT 2-1/2IN 1/4IN PRESSURE GAUGE D581689


AMETEK USG 505A PRESSURE GAUGE 2-1/2IN 1/4IN NPT D581695


WORKSMART WS-PE-GAGE-44 PRESSURE GAUGE 2-1/2IN 1/4IN NPT D581573


ASHCROFT 15W1001TH 01B XUC160 0-160PSI 1-1/2IN 1/8IN NPT PRESSURE GAUGE D588744


ASHCROFT 20W1005-H-02L-1?00 1/4"NPT 0-100PSI 2IN PRESSURE GAUGE D588322


AMETEK 163930 P500K 0-30PSI 2IN 1/8"NPT PRESSURE GAUGE D588326


AMETEK 005495A USG C505A -30-0IN-HG 0-30PSI 1/4IN NPT PRESSURE GAUGE D546398


ASHCROFT 30-0IN-HG 0-30PSI 1/4 IN NPT PRESSURE GAUGE D537717


ASHCROFT 30-0IN-HG 0-15PSI 1/2IN NPT PRESSURE GAUGE D537719


GORMAN RUPP 21-1348-02 LIQUID FILLED PRESSURE GAUGE 0-160PSI 1/4IN NPT D582067


FISHER 0-160PSI 1/4 IN NPT PRESSURE GAUGE D542042


TRERICE 800B1501BA100 0-60PSI 1-1/2 IN 1/8 IN NPT PRESSURE GAUGE D542034


TRERICE 800B D39112 0-60PSI 1-1/2 IN 1/8 IN NPT PRESSURE GAUGE D542037


ASHCROFT 35-1009-AW-02L-?600-XLJLL DURALIFE 0-600PSI 3-1/2 IN GAUGE D542127


ASHCROFT DURALIFE PRESSURE GAUGE 0-60PSI 1/4 IN NPT D578579


ASHCROFT 25W1005 H 02B DRESSER 0-60PSI 2-1/2 IN 1/4 IN PRESSURE GAUGE D545528


WINTERS PFQ904 PRESSURE GAUGE 0-100PSI 2-1/2IN 1/4IN NPT D592998


MOORE 3-1/2IN 1/4IN NPT 0-14PSI PRESSURE GAUGE D593009


ASHCROFT 20W1005-H-02L-2?00 PRESSURE GAUGE 0-200PSI 2IN 1/4IN NPT D585686


MARSH J4676 0-2000PSI 2-1/2 IN 1/4 IN NPT PRESSURE GAUGE D537534


NISSHIN R407C PRESSURE GAUGE 0-4MPA JIC-4 D578721


NISSHIN R407C COMPOUND PRESSURE GAUGE -0.1-0-1.6MPA JIC-4 D578722


ASHCROFT 35-1009-AW-02B-?3-15 GAUGE 3-15PSI 0-** 3-1/2IN 1/4IN NPT D585675


ASHCROFT TYPE 1008 0-1000PSI 4 IN 1/4 IN NPT PRESSURE GAUGE D537579


WEKSLER BY12YPS4CW PRESSURE GAUGE 0-2000PSI 2-1/2IN 1/4IN NPT D585682


ASHCROFT 20W1005-H-02B-1?00 PRESSURE GAUGE 0-100PSI 2IN 1/4IN NPT D585691


ASHCROFT 20W1005-H-02L-1?60 PRESSURE GAUGE 0-160PSI 2IN 1/4IN NPT D585766


ASHCROFT 20W1005-H-02L-3?0 PRESSURE GAUGE 0-30PSI 2IN 1/4IN NPT D585769


AMETEK USG 163272 P500K PRESSURE GAUGE 0-60PSI 2IN 1/4IN NPT D585772


AMETEK P844U 0-100PSI PRESSURE GAUGE 2-1/2 IN 1/8 IN NPT D578710


ASHCROFT TYPE 1008 0-160PSI 100MM 1/4 IN NPT PRESSURE GAUGE D578688


MEYLAN 20-200FPM 5/8 IN NPT GAUGE D546438


WIKA 8945217 432.12.100 SEALGAUGE 0-250PSI 3/4 IN NPT PRESSURE GAUGE D559450




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