Three characteristics of Ross Mont's intelligent pressure transmitter
Now the general intelligent transmitter is both hybrid intelligent transmitter digital signals and analog signals, and DCS communication to transfer the 4 ~ 20mA analog signal, and then used to set the zero point and the measuring range and remote calibration, the transmitter configuration and diagnosis in the superimposed on the digital signal. It is designed for compatibility with existing DCS, and is the transition product of the real sense of all digital intelligent transmitter (such as fieldbus type intelligent transmitter). Compared with the conventional analog transmission, the Rosemont intelligent transmitter has the following characteristics in its application:
The range of 1 range is wide and the range ratio is larger
Intelligent transmitters generally have a wide range of range, larger range, from 30:1 to 100:1, and some even 400:1. The range ratio of the transmitter refers to the ratio of the maximum measurement range (URV) to the minimum measurement range (LRV) of . The biggest advantage of intelligent transmitter range compared with conventional analog transmitter is that it can reduce inventory. At the same time, according to process requirements, it can change the range at any time without changing the table, without scruple. For example, Zhongyuan Dahua Refco Group Ltd because of the newly added 3 sets of melamine, intermediate by-products have CO2 medium return urea absorber for re absorption, and the absorption of CO2 will greatly increase the amount of ammonia into the medium pressure absorption tower, this instrument used to measure the ammonia to increase from 10t/h to 30t/h, then Monte Ross intelligent transmitter is very convenient, online adjust range can be, without having to replace instrument. If it is a conventional analog transmitter, a larger new meter will be replaced.
2 has the function of high and low pressure side conversion
The Ross Mont intelligent transmitter usually has the function of the high and low pressure side conversion, and the internal parameters can be adjusted by the handheld communication device. In the production process is encountered such a problem, because the instrument has been running for many years, connected to the transmitter tubing due to leakage in need of replacement, replacement of Monte Ross instruments operation found positive and negative phase tube reverse (because the pipe is longer, and with the heat pipe in a positive and negative compatibility to meet counter). If the 2 tubes are exchanged for a large amount of work. The intelligent transmitter has high and low voltage side conversion function. The parameter "D45:H/LSWAP" in the table is changed from NOROMAL (right side high voltage, left low pressure) to REVERSE (right side low voltage, left side high voltage). After reconfiguring, all the tables are normal, which saves time and effort.
3 simple and convenient maintenance
With a handheld communicator and intelligent transmitter communication optional in the transmitter site wiring terminal or the main control room control wiring terminal cabinet. So the instrument maintenance personnel can carry out range modification, parameter setting and instrument maintenance in the relatively safe and well controlled control room. Zhongyuan Dahua Refco Group Ltd urea plant has a liquid ammonia tank level gauge. It always indicates errors during the start-up stage. The reason is that the density of liquid ammonia at the start-up stage and the normal production stage causes the instrument indication is not allowed. It can only set a measuring range for the transmitter when driving, and then a measuring range is set when the production is normal. In addition, it is easy to leak ammonia and other harmful gases when driving, and the instrument maintenance personnel have to wear a gas mask to handle each time. If the intelligent transmitter is used to replace the original analog instrument, the above problems can be solved at the same time. In the control room, the parameters of the instrument can be modified to ensure the personal safety of the personnel. Note that the communicator cannot directly connect the instrument control circuit for power supply at both ends of the transmitter power, reason is the power for the low impedance, handheld communicator is unable to read the information in it at both ends, general requirements for loop resistance in 250 ~ 600, the resistance is too small to be communication, too much work will be abnormal resistance transmitter.