Trane TRG-TRC012-EN Controls And Starter

TRG-TRC012-EN 15

period one

Components

notes

Controls and Starter

A microprocessor-based control panel is provided on the chiller to provide

accurate chilled water control as well as monitoring, protection, and adaptive

limit functions. These controls monitor the chiller’s operation and prevent the

chiller from operating outside of its limits. They can compensate for unusual

operating conditions while keeping the chiller running by modulating system

components, rather than simply tripping off due to a safety setting.

Furthermore, when problems do occur, diagnostic messages aid in

troubleshooting.

This control system not only provides accurate, optimized control and

protection for the chiller, but permits interfacing with a building automation

system for integrated system control. In a chilled water system, optimal control

is a system-wide issue, not just a chiller issue.

Because compressor motors create such a large electrical load, they cannot be

started and stopped using a simple switch or plug. A starter provides a linkage

between the motor and the electrical distribution system. Its primary function is

to connect (start) and disconnect (stop) the chiller from the line. The starter also

includes a transformer that provides power to the chiller control panel and

components to perform overload protection and current-limiting functions.

Finally, the application of a chiller starter also requires considering a means of

disconnect and short circuit protection.

Controls And Starter

control

control

panel

panel

starter

starter

Figure 24

Contents

Main Page Preface A Trane Air Conditioning Clinic Contents Page Introduction Chilled Water System helical-rotary absorption centrifugal Introduction water-cooled air-cooled Helical-Rotary Water Chillers period one period one Helical-Rotary Water Chiller Compressor Page Page Page Oil Separator Oil Separator Oil Supply System notes Condenser Condenser Expansion Device Electronic Expansion Valve Liquid/Vapor Separator Orifice Plates Liquid/Vapor Separator notes Evaporator Flooded Evaporator Direct Expansion Evaporator Controls and Starter Controls And Starter period two Refrigeration Cycle period two notes p-h) PressureEnthalpy ( liquid vapor Refrigeration Cycle Refrigerants Thermodynamic Characteristics period three period three Slide Valve Full Load Part Load Unloading Slide Valve Operation period four period four Maintenance Considerations ASHRAE Guideline 3 Page Mechanical Components Heat Transfer Surfaces notes Fluid Analysis period five Air-Cooled or Water-Cooled Condensing period five Air-Cooled or Water-Cooled water-cooled Comparison air-cooled notes Condensing Temperature Control Condensing Temperature Control Cooling Tower Bypass Constant or Variable Evaporator Water Flow Constant or Variable Flow Limitations Short Evaporator Water Loops Short Evaporator Water Loops Short Evaporator Water Loops Equipment Certification Standards ARI Standard 550/590 ARI Standard 550/590 40 Lets review the main concepts that were covered in this clinic on helical-rotary water chillers. period six ReviewPeriod 1 period six ReviewPeriod 2 ReviewPeriod 3 ReviewPeriod 4 ReviewPeriod 5 Engineers Newsletter Quiz Questions for Period 1 Questions for Period 2 Quiz Questions for Period 3 Questions for Period 4 Questions for Period 5 Answers Page Glossary BUSINESS REPLY MAIL Comment Card Helical-Rotary Water Chillers Response Card