ICS TRIPLEX T3480DCS工控模塊備件
應(yīng)為Rload=5 V/0.020 A=250?. GE Multilin 469電機(jī)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(jiān)測(cè)定子、軸承、環(huán)境或其他溫度監(jiān)測(cè)的12個(gè)RTD輸入。每個(gè)RTD的類型可現(xiàn)場(chǎng)編程為100? 鉑（DIN 43760），100? 鎳，120? 鎳或10? 銅RTD必須為三線式。每?jī)蓚€(gè)RTD共享一個(gè)共同的回報(bào)。如果三根導(dǎo)線的長(zhǎng)度相同，RTD電路會(huì)補(bǔ)償導(dǎo)線電阻。引線電阻不應(yīng)超過(guò)25? 對(duì)于鉑/鎳RTD或3? 銅RTD的每根引線。應(yīng)使用屏蔽電纜，以防止工業(yè)環(huán)境中的噪聲拾取。RTD電纜應(yīng)靠近接地金屬外殼，遠(yuǎn)離高電磁或無(wú)線電干擾區(qū)域。RTD引線不應(yīng)與大電流載電線相鄰或在同一導(dǎo)管中。圖2-18：RTD接線重要事項(xiàng)：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(gè)電路只能使用一個(gè)接地參考。相對(duì)于469安全接地，Transorbs將此隔離限制在±36 V。b） 減少RTD引線數(shù)量應(yīng)用469要求從每個(gè)RTD帶回三根引線：熱引線、回流引線和補(bǔ)償引線。這可能相當(dāng)昂貴。然而，對(duì)于第一個(gè)RTD，可以將所需的引線數(shù)量減少到3根，對(duì)于每個(gè)連續(xù)的RTD，可以減少到1根。有關(guān)此應(yīng)用的接線配置，請(qǐng)參閱下圖。圖2–19：減少布線電阻每個(gè)電阻式溫度檢測(cè)器的火線必須照常運(yùn)行。然而，補(bǔ)償和返回導(dǎo)線只需用于第一個(gè)RTD。在電機(jī)RTD接線盒上，RTD回路導(dǎo)線必須與盡可能短的跳線一起跨接。補(bǔ)償導(dǎo)線必須在469處跨接在一起。電機(jī)起動(dòng)器3線屏蔽電纜電機(jī)起動(dòng)器RTD端子電機(jī)最大總導(dǎo)線電阻25歐姆（鉑和鎳RTD）3歐姆（銅RTD）電機(jī)起動(dòng)器RTD終端電機(jī)定子或軸承806819A5.CDR B1 A1 A2 A3熱補(bǔ)償回路屏蔽底盤接地RTD傳感RTD#1 469繼電器注釋808722A1.CDR熱補(bǔ)償RTD回路補(bǔ)償高溫補(bǔ)償RTD回路A1 A2 A3 A4 A5 A6 A7 A8 L1 L2 L3 L4 L5 L6 L7無(wú)連接469 J1 J2電機(jī)控制接線盒電機(jī)RTD1+–RTD2+–RTD3+–J3 J4 2-16 469電機(jī)管理繼電器GE Multilin 2.2電氣2安裝2注意，每個(gè)RTD上產(chǎn)生的錯(cuò)誤等于RTD回路跨接器上的電壓降。該誤差隨著每個(gè)連續(xù)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(dǎo)線的長(zhǎng)度和規(guī)格，以及不良連接導(dǎo)致的任何誤差。對(duì)于10以外的RTD類型? 銅，跳線引入的誤差可以忽略不計(jì)。盡管這種RTD布線技術(shù)降低了布線成本，但以下數(shù)據(jù)
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
