Daikin EWAD900BJYNN/A [152/346] System architecture

The Digital Controller ESIE07-04

2–12 Part 2 – Functional Description

2.2 System Architecture

General description The Microtech II C Plus control panel contains a microprocessor based controller which provides all

monitoring and control functions required for the safe, efficient operation of the Chiller. The operator

can monitor all operating conditions by using the panel’s built in 4 line by 20 character keypad/display

or by using an IBM compatible computer running MicroPlant monitor software release 2.0 and later. In

addition to providing all normal operating controls, the PlantVisor 1.0 controller monitors all safety

devices on the unit and will take corrective action if the chiller is operating of it’s normal design

conditions. If a fault condition develops, the controller will shut the system down and activate an alarm

output. Important operating conditions at the time an alarm condition occurs are retained in the

controller’s memory to aid in troubleshooting and fault analysis.

The system is protected by a password scheme which only allows access by authorized personnel. A

password must be entered into the panel keypad by the operator before any configuration may be

altered

Flow chart The system architecture is based on the use of one PCO² Carel controller to manage two

compressors; an additional PCOe expansion board is used to manage economizer when required.

The system is able to control units equipped with electronic expansion valve; in this case the use of

an electronic Carel Driver for each valve is required.

Display

EEXV Driver

pLAN

J23 port

Supervisory Systems

pLAN

OPTIONAL

pLAN

pCOe

Expansion

RS485

pCO2 controller #1

Compressor #1 & Compressor #2

pCO2 controller #2

Compressor #3 & Compressor #4