羅斯蒙特248RANA溫度變送器(導(dǎo)軌式)系列具備基于微處理器的電子元件，具有優(yōu)異性能和較高靈活性。 采用故障模式的剛性故障跨接線 1 年的長(zhǎng)期穩(wěn)定性 線性化輸出與輸入/輸出隔離 基于微處理器的通用變送器 RTD、熱電偶、mV 或 Ohm 輸入 可安裝于導(dǎo)軌安裝套件內(nèi)，專門(mén)為控制室封閉通道而設(shè)計(jì) 羅斯蒙特248導(dǎo)軌式溫度變送器典型型號(hào): Rosemount羅斯蒙特248RANA Rosemount羅斯蒙特

248RANAQ4 Features of the Model 248 include: ?Accepts inputs from a wide variety of RTD and thermocouple sensors ?Configuration using HART protocol ?Electronics that are completely encapsulated in epoxy and enclosed in a plastic housing, making the transmitter extremely durable and ensuring long-term reliability ?A compact size and three housing options allowing mounting flexibility in the field ?Assembly including the transmitter,sensor, housing, thermowell, and extension accessories that can be ordered in one model number Electrical temperature sensors such as RTDs and thermocouples produce low-level signals proportional to their sensed temperature. The Model 248 converts the low-level sensor signal to a standard 4-20mA dc signal that is relatively insensitive to lead length and electrical noise. This current signal is then transmitted to the control room via two wires. The transmitter can be commissioned before or after installation. It may be useful to commission it on the bench,before installation,to ensure proper operation and to become familiar with its functionality. Make sure the instruments in the loop are installed in accordance with intrinsically safe or non-incendive field wiring practices before connecting a HART communicator in an explosive atmosphere. 

羅斯蒙特248溫度監(jiān)測(cè)裝配件設(shè)計(jì)符合溫度監(jiān)測(cè)應(yīng)用要求。采用HART?協(xié)議的該部安裝變送器可與多種傳感器、部接線盒和熱電偶套管配套訂購(gòu)。所有這些產(chǎn)品均采用能夠提供、讀數(shù)的羅斯蒙特產(chǎn)品設(shè)計(jì)。

 1、提高溫度測(cè)量的精度/總體性能

a、變送器按照傳感器的實(shí)際曲線微調(diào)其內(nèi)部的溫度曲線，可大地降低傳感器互換性誤差（達(dá)75%）；644H和644R型智能溫度變送器-變送器與傳感器比對(duì)功能、匹配功能3144和3244MV型智能溫度變送器-變送器與傳感器匹配功能 

b、熱電偶測(cè)量時(shí)，變送器將毫伏信號(hào)轉(zhuǎn)換為對(duì)噪聲較不敏感的4-20mA信號(hào)，提高抗干擾的能力，并大大縮短補(bǔ)償導(dǎo)線的長(zhǎng)度； 

c、熱電偶的冷端補(bǔ)償誤差； 244EH和244ER型PC機(jī)可編程溫度變速器，644H 和644R型智能溫度變送器，以及3144和3244MV型智能溫度變送器，均具有自動(dòng)的冷端補(bǔ)償功能 

d、3244MV型智能溫度變送器有溫差測(cè)量功能，溫差測(cè)量精度比使用兩臺(tái)變送器分別測(cè)量后送至DCS（或?qū)蓚€(gè)傳感器的信號(hào)直接送至DCS）后計(jì)算出溫差的方式的精度高幾倍。

 2、安裝方便 

a、使用變送器后，所有的電纜均相同，為普通的銅導(dǎo)線 

b、拉伸銅電纜比拉伸熱電偶的補(bǔ)償導(dǎo)線容易 

c、電纜的布線容易，沒(méi)有避開(kāi)電源的特殊規(guī)則 

 3、靈活性大 

a、用溫度變送器時(shí)，溫度測(cè)量如其他過(guò)程測(cè)量（如壓力、液位、流量）一樣均是4-20mA信號(hào)，DCS可使用相同的I/O卡 

b、溫度輸入可以與其他變送器的輸入組合在一起,配置熱電偶和熱電阻的I/O卡

 4、減少安裝、維護(hù)和運(yùn)行等的總體費(fèi)用 

a、銅電纜比熱電偶的補(bǔ)償導(dǎo)線 

b、使用銅電纜，單的電纜架和導(dǎo)線管，意味著安裝 

c、DCS的I/O卡類型相同，減少卡件數(shù)量和不使用的接線端子數(shù)量 

d、智能型變送器有診斷功能，可和判斷出是傳感器故障還是過(guò)程報(bào)警，從而減少到現(xiàn)場(chǎng)維護(hù)的次數(shù)，這意味著很大的維修節(jié)約 

e、好的溫度測(cè)量性能，可提高生產(chǎn)率，意味著很大的生產(chǎn)節(jié)約

 Industry’s best total performance,a a flexible Coplanar platform,and installed five-year stability,has made the Rosemount 3051 the standard in pressure measurement. Inustry’s best-in-class total performance of ±0.15% Total performance is the true measure of “real-world”transmitter performance. Using superior sensor technology and engineered for optimal performance,the 3051 delivers unprecedented ±0.04% reference accuracy,resulting in total operating performance of ±0.15%. Superior total performance equates to reduced variability and improved plant safety.