羅斯蒙特248RANA溫度變送器(導軌式)系列具備基于微處理器的電子元件，具有優異性能和較高靈活性。 采用故障模式的剛性故障跨接線 1 年的長期穩定性 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 可安裝于導軌安裝套件內，專門為控制室封閉通道而設計 羅斯蒙特248導軌式溫度變送器典型型號: 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溫度監測裝配件設計符合溫度監測應用要求。采用HART?協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。所有這些產品均采用能夠提供、讀數的羅斯蒙特產品設計。

 1、提高溫度測量的精度/總體性能

a、變送器按照傳感器的實際曲線微調其內部的溫度曲線，可大地降低傳感器互換性誤差（達75%）；644H和644R型智能溫度變送器-變送器與傳感器比對功能、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、熱電偶測量時，變送器將毫伏信號轉換為對噪聲較不敏感的4-20mA信號，提高抗干擾的能力，并大大縮短補償導線的長度； 

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

d、3244MV型智能溫度變送器有溫差測量功能，溫差測量精度比使用兩臺變送器分別測量后送至DCS（或將兩個傳感器的信號直接送至DCS）后計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，為普通的銅導線 

b、拉伸銅電纜比拉伸熱電偶的補償導線容易 

c、電纜的布線容易，沒有避開電源的特殊規則 

 3、靈活性大 

a、用溫度變送器時，溫度測量如其他過程測量（如壓力、液位、流量）一樣均是4-20mA信號，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、維護和運行等的總體費用 

a、銅電纜比熱電偶的補償導線 

b、使用銅電纜，單的電纜架和導線管，意味著安裝 

c、DCS的I/O卡類型相同，減少卡件數量和不使用的接線端子數量 

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程報警，從而減少到現場維護的次數，這意味著很大的維修節約 

e、好的溫度測量性能，可提高生產率，意味著很大的生產節約

 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.