Reference Manual

00809-0100-4697, Rev EA October 2011

Rosemount 848T

Out of Service (OOS)

The block is not processing its tasks. When the resource block is in OOS, all blocks within the resource (device) are forced into OOS. The BLOCK_ERR parameter shows Out of Service. In this mode, changes can be made to all configurable parameters. The target mode of a block may be restricted to one or more of the supported modes.

Alarm Detection

A block alarm will be generated whenever the BLOCK_ERR has an error bit set. The types of block error for the resource block are defined above. A write alarm is generated whenever the WRITE_LOCK parameter is cleared. The priority of the write alarm is set in the following parameter:

•WRITE_PRI

Table 3-4. Alarm Priority Levels

Number

Description

0

The priority of an alarm condition changes to 0 after the condition that caused the

 

alarm is corrected.

1

An alarm condition with a priority of 1 is recognized by the system, but is not

 

reported to the operator.

2

An alarm condition with a priority of 2 is reported to the operator, but does not

 

require operator attention (such as diagnostics and system alerts).

3-7

Alarm conditions of priority 3 to 7 are advisory alarms of increasing priority.

8-15

Alarm conditions of priority 8 to 15 are critical alarms of increasing priority.

 

Status Handling

 

There are no status parameters associated with the resource block.

PlantWeb™ Alerts

The alerts and recommended actions should be used in conjunction with

 

“Operation and Maintenance” on page 4-1.

 

The Resource Block will act as a coordinator for PlantWeb alerts. There will

 

be three alarm parameters (FAILED_ALARM, MAINT_ALARM, and

 

ADVISE_ALARM) which will contain information regarding some of the device

 

errors which are detected by the transmitter software. There will be a

 

RECOMMENDED_ACTION parameter which will be used to display the

 

recommended action text for the highest priority alarm and a HEALTH_INDEX

 

parameters (0 - 100) indicating the overall health of the transmitter.

 

FAILED_ALARM will have the highest priority followed by MAINT_ALARM

 

and ADVISE_ALARM will be the lowest priority.

 

FAILED_ALARMS

 

A failure alarm indicates a failure within a device that will make the device or

 

some part of the device non-operational. This implies that the device is in

 

need of repair and must be fixed immediately. There are five parameters

 

associated with FAILED_ALARMS specifically, they are described below.

 

FAILED_ENABLED

 

This parameter contains a list of failures in the device which makes the

 

device non-operational that will cause an alert to be sent. Below is a list of

 

the failures with the highest priority first.

3-11

Page 32 Page 34
Page 33
Image 33
Emerson 848T manual PlantWeb Alerts, Out of Service OOS, Alarm Detection, Status Handling
Page 32 Page 34

848T specifications

The Emerson 848T is a state-of-the-art temperature transmitter designed for accurate and reliable temperature measurement in various industrial applications. This device has gained recognition for its advanced features and robust performance, making it a popular choice among engineers and technicians in the field.

One of the key highlights of the Emerson 848T is its unique dual-channel capability, which allows it to seamlessly monitor two temperature sources simultaneously. This functionality is particularly beneficial in processes where multiple temperature points need to be assessed, optimizing efficiency and reducing the need for additional equipment. It supports various sensor types, including thermocouples, RTDs, and resistance temperature detectors, making it versatile for different applications.

The 848T is equipped with sophisticated digital processing technology, which enhances its accuracy and stability. It features a 24-bit analog-to-digital converter, ensuring precise measurement and minimizing drift over time. Moreover, the device boasts a wide operating temperature range, accommodating ambient conditions from -40°C to 85°C. This durability makes it suitable for harsh environments commonly encountered in industries such as oil and gas, pharmaceuticals, and power generation.

Another significant characteristic of the Emerson 848T is its configurable output options. Users can choose from a range of output signals, including 4-20 mA, which provides a standard interface for integration into existing control systems. Additionally, it offers a HART communication protocol, allowing for easy configuration, calibration, and diagnostics through a digital interface. This feature enhances the transmitter's usability, enabling operators to perform adjustments without direct access to the device.

The device is designed with user-friendliness in mind. Its intuitive setup procedure and robust graphical user interface simplify the commissioning process, ensuring that even those new to the technology can easily navigate the system. An integrated LCD display provides real-time readings and status information, facilitating monitoring at a glance.

In summary, the Emerson 848T temperature transmitter combines reliable performance, user-friendly design, and advanced digital technologies. Its dual-channel capability, wide sensor compatibility, and adjustable output options make it an essential tool for achieving precise temperature measurements in various industrial settings. With these compelling features, the Emerson 848T stands out as a leading choice for professionals seeking accuracy and efficiency in their temperature monitoring applications.
Top Page Image Contents