Alarm Descriptions and Solutions

6.0ALARM DESCRIPTIONS AND SOLUTIONS

The Advanced Microprocessor (AM) and the Advanced Microprocessor with Graphics (AG) Control systems will audibly and visually annunciate all Enabled alarms, including the four (4) custom alarms. With the AM & AG Controls, the customer alarms can be from the optional alarm list and/or can have their own fully custom text. Two (2) alarms may be selected as custom for AM and four (4) can be custom for AG. The custom alarm inputs are 24 Volts AC which is available from the Liebert unit. Alarms are wired from terminal 24 through a normally open contact to locations 50, 51, 55, and 56, respectively, for alarms 1 through 4.

The AM and AG alarms can be delayed from 0 to 255 seconds (see Setup Alarms on page 10). The AM alarms can be Enabled or Disabled (also in Setup Alarms on page 10). Also, the AM alarms can be programmed to energize the Common Alarm Relay or to “alarm only” and not energize the Com- mon Alarm Relay.

The AG alarms can be selected as Warning, Urgent, or Disabled. If selected to be a Warning, they are annunciated after the Time Delay but do not energize the Common Alarm Relay. If selected as Urgent, they are annunciated after the Time Delay as a Warning alarm and then re-annunciated after a user programmable period from 0 minutes to 999 hours as an Urgent alarm. When annunci- ated as an Urgent alarm, the Common Alarm Relay is activated. The custom alarm inputs of the AG can be designated “Status Only.” As Status Only, the custom alarm input is referenced as a digital input and is no longer treated as an alarm. It is for monitoring only and can be reviewed by selecting “Analog/Digital Inputs.”

When a new alarm occurs, it is displayed on the screen and the audible alarm is activated. If commu- nicating with a Liebert Site Product, the alarm is also transmitted. The display will also show a mes- sage to “Press Enter Key to Silence” the alarm. After the alarm is silenced, the display will return to the Normal Status Display. For the AG, the bell and hammer are shown at the top of the Normal Sta- tus Display. For the AM, the bottom line will display the number of Active Alarms. For the SM, the alarm is displayed by a lighted LED next to the alarm text. The active alarms can be reviewed on the Advanced Microprocessor Controls by selecting “Active Alarms.”

The alarms can also be silenced through communications with a Liebert Site Products unit. Most alarms will reset automatically when the alarm condition is no longer present and only after it has been acknowledged by being “Silenced.” The exceptions are:

a.The three software alarms: Loss of Power, Low Suction Pressure, and Short Cycle which reset automatically 90 minutes after being “Silenced” or acknowledged.

b.(2) Some alarms such as overloads and high pressure switches may require a manual reset depending on your model.

A history of the alarms (10 for AM units and 60 for AG units) is retained in nonvolatile memory (for AM information, see 3.3.3 - Alarm History Log; for AG information, see 4.4.2 - Alarm History Log).

This section provides a definition of each available alarm. Troubleshooting suggestions are included. Refer to 8.0 - Troubleshooting for more details. If you need assistance with your environmental con- trol system, contact your Liebert supplier.

6.1Standard Alarms

6.1.1Change Filter

Periodically, the return air filters in the environmental units must be changed. The Change Filter alarm notifies the user that filter replacement is necessary. A differential air pressure switch closes when the pressure drop across the filters becomes excessive. The switch is adjustable using the proce- dure on the switch label.

6.1.2Compressor Overload

The control break compressor safety stats located internal to the Carlyle compressors are tripped when an overload condition occurs. When a Copeland compressor is used, an optional tri-block over- load device can be used for each compressor. Compressor overload may be manual or automatic reset, depending on your model. Overload is located at the electric connection box on the compressor. Note that compressor #1 is the top compressor and compressor #2 is the bottom one.

44

Page 51 Page 53
Page 52
Image 52
Emerson VH, DE, VE, DH manual Standard Alarms, Alarm Descriptions and Solutions, Change Filter, Compressor Overload
Page 51 Page 53

VE, DH, VH, DE specifications

Emerson is a well-known brand in the field of automation solutions, offering a range of products that cater to various industries. Among its diverse portfolio, Emerson’s products like DE (Digital Electronics), VH (Variable Frequency Drives), DH (Distributed Control Systems), and VE (Valve Positioners) stand out for their advanced features, cutting-edge technologies, and unique characteristics.

Digital Electronics (DE) from Emerson represents the backbone of modern automation systems. These devices are characterized by their highly reliable digital communication capabilities, providing robust solutions for process monitoring and control. DE products integrate seamlessly with various automation platforms, allowing for easy data exchange and system interoperability. The advanced analytics embedded in these systems enable predictive maintenance strategies, enhancing overall operational efficiency.

Variable Frequency Drives (VH) are integral to motor control technologies, maximizing energy efficiency in various applications. Emerson's VH drives are designed for flexibility, supporting multiple motor types and configurations. These drives utilize pulse width modulation (PWM) technology, allowing for precise speed control and improved application performance. Their built-in protection features help extend motor life, prevent downtime, and reduce maintenance costs. Furthermore, the user-friendly interfaces of VH drives facilitate quick setup and troubleshooting.

Distributed Control Systems (DH) from Emerson provide a holistic approach to managing complex industrial processes. They enable centralized control while ensuring that local operations continue seamlessly. DH systems are characterized by their modular architecture, making them highly scalable and adaptable to changing operational needs. Advanced control algorithms within these systems help optimize processes, ensuring maximum productivity. Additionally, their enhanced cybersecurity features protect critical industrial operations from potential threats.

Emerson's Valve Positioners (VE) play a crucial role in regulating flow and pressure in various processes. These devices provide precise positioning capabilities, enhancing the performance of control valves. The VE systems incorporate smart technologies such as adaptive control and diagnostics, allowing them to self-tune and deliver accurate performance over time. Their compact design and robust build ensure they operate effectively in challenging environments.

In summary, Emerson's DE, VH, DH, and VE offerings embody the latest innovations in automation technology. Their main features, including digital communication, energy efficiency, scalability, and precision control, cater to the diverse demands of modern industries. With these products, Emerson not only enhances operational efficiency but also paves the way for intelligent automation solutions that are crucial for the future of industrial processes.
Top Page Image Contents