ICS TRIPLEX T3480DCS工控模塊備件
應為Rload=5 V/0.020 A=250?. GE Multilin 469電機管理繼電器2-15 2安裝2.2電氣2 2.2.8 RTD傳感器連接a）描述469最多可監測定子、軸承、環境或其他溫度監測的12個RTD輸入。每個RTD的類型可現場編程為100? 鉑（DIN 43760），100? 鎳，120? 鎳或10? 銅RTD必須為三線式。每兩個RTD共享一個共同的回報。如果三根導線的長度相同，RTD電路會補償導線電阻。引線電阻不應超過25? 對于鉑/鎳RTD或3? 銅RTD的每根引線。應使用屏蔽電纜，以防止工業環境中的噪聲拾取。RTD電纜應靠近接地金屬外殼，遠離高電磁或無線電干擾區域。RTD引線不應與大電流載電線相鄰或在同一導管中。圖2-18：RTD接線重要事項：RTD電路與模擬輸入電路和模擬輸出電路作為一組隔離。三個電路只能使用一個接地參考。相對于469安全接地，Transorbs將此隔離限制在±36 V。b） 減少RTD引線數量應用469要求從每個RTD帶回三根引線：熱引線、回流引線和補償引線。這可能相當昂貴。然而，對于第一個RTD，可以將所需的引線數量減少到3根，對于每個連續的RTD，可以減少到1根。有關此應用的接線配置，請參閱下圖。圖2–19：減少布線電阻每個電阻式溫度檢測器的火線必須照常運行。然而，補償和返回導線只需用于第一個RTD。在電機RTD接線盒上，RTD回路導線必須與盡可能短的跳線一起跨接。補償導線必須在469處跨接在一起。電機起動器3線屏蔽電纜電機起動器RTD端子電機最大總導線電阻25歐姆（鉑和鎳RTD）3歐姆（銅RTD）電機起動器RTD終端電機定子或軸承806819A5.CDR B1 A1 A2 A3熱補償回路屏蔽底盤接地RTD傳感RTD#1 469繼電器注釋808722A1.CDR熱補償RTD回路補償高溫補償RTD回路A1 A2 A3 A4 A5 A6 A7 A8 L1 L2 L3 L4 L5 L6 L7無連接469 J1 J2電機控制接線盒電機RTD1+–RTD2+–RTD3+–J3 J4 2-16 469電機管理繼電器GE Multilin 2.2電氣2安裝2注意，每個RTD上產生的錯誤等于RTD回路跨接器上的電壓降。該誤差隨著每個連續RTD的增加而增加。VRTD1=VRTD1 VRTD2=VRTD2+VJ3 VRTD3=VRTD3+VJ3+VJ4等。此誤差直接取決于跳線所用導線的長度和規格，以及不良連接導致的任何誤差。對于10以外的RTD類型? 銅，跳線引入的誤差可以忽略不計。盡管這種RTD布線技術降低了布線成本，但以下數據
would be Rload = 5 V / 0.020 A = 250 ?. GE Multilin 469 Motor Management Relay 2-15 2 INSTALLATION 2.2 ELECTRICAL 2 2.2.8 RTD SENSOR CONNECTIONS a) DESCRIPTION The 469 monitors up to 12 RTD inputs for Stator, Bearing, Ambient, or Other temperature monitoring. The type of each RTD is field programmable as 100 ? Platinum (DIN 43760), 100 ? Nickel, 120 ? Nickel, or 10 ? Copper. RTDs must be three wire type. Every two RTDs shares a common return. The RTD circuitry compensates for lead resistance, provided that each of the three leads is the same length. Lead resistance should not exceed 25 ? per lead for platinum/nickel RTDs or 3 ? per lead for copper RTDs. Shielded cable should be used to prevent noise pickup in the industrial environment. RTD cables should be kept close to grounded metal casings and away from areas of high electromagnetic or radio interference. RTD leads should not be run adjacent to or in the same conduit as high current carrying wires. Figure 2–18: RTD WIRING IMPORTANT: The RTD circuitry is isolated as a group with the Analog Input circuitry and the Analog Output circuitry. Only one ground reference should be used for the three circuits. Transorbs limit this isolation to ±36 V with respect to the 469 safety ground. b) REDUCED RTD LEAD NUMBER APPLICATION The 469 requires three leads to be brought back from each RTD: Hot, Return and Compensation. This can be quite expensive. It is however possible to reduce the number of leads required to 3 for the first RTD and 1 for each successive RTD. Refer to the figure below for wiring configuration for this application. Figure 2–19: REDUCED WIRING RTDS The Hot line would have to be run as usual for each RTD. The Compensation and Return leads, however, need only be run for the first RTD. At the motor RTD terminal box, the RTD Return leads must be jumpered together with as short as possible jumpers. The Compensation leads must be jumpered together at the 469. MOTOR STARTER 3 WIRE SHIELDED CABLE MOTOR RTD TERMINALS IN MOTOR STARTER RTD TERMINALS AT MOTOR Maximum total lead resistance 25 ohms (Platinum & Nickel RTDs) 3 ohms (Copper RTDs) Route cable in separate conduit from current carrying conductors RTD IN MOTOR STATOR OR BEARING 806819A5.CDR B1 A1 A2 A3 HOT COMPENSATION RETURN SHIELD CHASSIS GROUND RTD SENSING RTD #1 469 RELAY NOTE 808722A1.CDR Hot Compensation RTD Return Compensation Hot Hot Compensation RTD Return A1 A2 A3 A4 A5 A6 A7 A8 L1 L2 L3 L4 L5 L6 L7 No connection 469 J1 J2 Motor Control Terminal Box Motor RTD1 + – RTD2 + – RTD3 + – J3 J4 2-16 469 Motor Management Relay GE Multilin 2.2 ELECTRICAL 2 INSTALLATION 2 Note that an error is produced on each RTD equal to the voltage drop across the jumper on the RTD return. This error increases with each successive RTD added. VRTD1 = VRTD1 VRTD2 = VRTD2 + VJ3 VRTD3 = VRTD3 + VJ3 + VJ4, etc. This error is directly dependent on the length and gauge of the wire used for the jumpers and any error introduced by a poor connection. For RTD types other than 10 ? Copper, the error introduced by the jumpers is negligible. Although this RTD wiring technique reduces the cost of wiring, the following d
