Chapter 6 Micro-Processing Controller 31
Liebert.CRV+ Series Air Cooled Precision Air Conditioner User Manual
Chapter 6 Micro-Processing Controller
This chapter gives a detailed description on feature, appearance, LCD screen, control buttons, control interface and
menu structure of the micro-processing controller of the Liebert.CRV+ air-cooled series air conditioner.
6.1 Feature
The micro-processing controller has the following features:
1. Adopt menu operation. It can monitor and display the operation status of AC unit to keep the environment within a
setting range.
2. Adopt a 128 × 64 dot LCD screen with white backlight. The user interface is easy-to-use.
3. Provide three-level password protection to prevent unauthorized operation effectively.
4. Provide the functions, including self-recovery upon power failure, high-voltage & low-voltage protection, phase loss
protection and automatic phase-sequence switching upon anti-phase.
5. Accurately know the running time of important components through menu operation.
6. The expert-level fault diagnose system can automatically display the current fault information to facilitate
maintenance personnel in equipment maintenance.
7. Store up to 200 historical alarm records.
8. Configured with an RS485 port. Adopt MODBUS-RTU communication protocol.
6.2 Appearance
The appearance of the micro-processing controller is shown in Figure 6-1.
Run indicator Alarm indicator
ESC button
ENT button
ON/OFF button
LCD screen
UP button
DOWN button
Figure 6-1 Appearance of the micro-processing controller
6.3 LCD Screen
The LCD screen displays English menus with white backlight. When the system is operating normally, in the upper
part of the LCD screen, it displays the settings and actual values of current air supply temperature (first queue) &
humidity (second queue), and air return temperature (the third queue displays air return temperature by default, when
the compressor mode or fan mode is set to ‘Remote’, the queue displays remote temperature). In the lower part of
the LCD screen, it displays unit output status (fan, cooling, heating, dehumidifying and humidifying), unit mode (single,
teamwork), and unit operation status (off, running, standby, locked), as shown in Figure 6-2.
