Carrier PC211 User Manual

19XL

50/60 Hz

Hermetic Centrifugal Liquid Chillers

®

with HCFC–22 and HFC–134a

Start-Up, Operation, and Maintenance Instructions

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and
without incurring obligations.

PC 211 Catalog No. 531-94512-94 Form 19XL-3SS Replaces: 19XL- 2SS

Copyright

Carrier Corpor ation 1994

©

Safety Considerations

Centrifugal liquid chillers are designed to provide safe and reliable service when
operated within design specifications. When operating this equipment, use good
judgement and safety precautions to avoid damage to equipment and property or injury
to personnel.

Be sure you understand and follow the procedures and safety precautions contained
in the machine instructions as well as those listed in this guide.

DANGER

DO NOT VENT refrigerant relief devices within a building. Outlet from rupture
disc or re lie f v al ve mu st be vent e d ou t doo rs in a c co rd an ce with the la tes t e dit i on
of ANS I/ASHRAE 15 (Ameri can Nat io nal Sta nd ards In st itute /American Society of
Heating, Refrigeration, and Air Conditioning Engineers). The accumulation of
ref rigerant in an enclosed spa ce can dis pl ace ox ygen and cause asphyxiation .

PROVIDE a dequ a te vent il a ti on in a c cordance with ANSI/ASHRAE 1 5 , es peciall y
for enclosed and low overhead spaces. Inhalation of high concentrations of
vapor is harmful and may cause heart irregularities, unconsciousness, or death.
Misuse can be fata l. Va po r is heavi er than air and reduces the amount o f oxygen
available for breathing. Product causes eye and skin irritation. Decomposition
pro ducts are haza rdous.

DO NOT USE OXYGEN to purge lines or to pressurize a machine for any purpose.
Oxygen gas reacts violently with oil, grease, and other common substances.

NEVER EXCEED specified test pressures. VERIFY the allowable test pressure by
che cking the instruct io n literature and the design press ures on th e equipment
nameplate.

DO NOT USE air for leak testing. Use only refrigerant or dry nitrogen.
DO NO T VALVE O FF any safe t y device.
BE SURE that all pressure relief devices are properly installed and functioning

befor e ope r ati ng an y mac hine.

!

DANGER

WARNING

DO NOT WELD OR FLAM E CUT any refri gerant li ne or vessel un t il all refrigerant
(

liquid and vapor

placed with dry air or nitrogen and the work area should be well ventilated.

Refr ig erant in con t act with an open flame pr od uces toxic gases.

DO NOT US E eyebol t s or eyebolt ho les to rig machin e sections or the entire
assemb ly.

DO NOT work on high-voltage equipment unless you are a qualified electrician.
DO NOT WORK ON electrical components, including control panels, switches,

sta rte r s, or oil heate r until you a r e sur e AL L P OW E R I S OFF and no re si du al v ol t ­age can le ak f rom ca pacitors or sol id-st at e components.

LOCK OPEN AND TAG electrical circuits during servicing. IF WORK IS INTER­RUPTE D, confi rm t hat all ci rcuit s are deenergized before resuming work.

DO NOT siphon refrigerant .
AVOID SPILLING liquid refrigerant on skin or getting it into the eyes. USE

SAFETY GOGGLES. Wash any spills from the skin with soap and water. If liquid
refrigerant enters the eyes, IMMEDIATELY FLUSH EYES with water and consult
a ph y sician.

NEVER APPLY an open flame or live steam to a refrigerant cylinder. Dangerous
over pressu re can result. Wh en it is ne cessar y t o he at ref rigerant , u se only
warm (110 F [43 C]) water.

!

) has been removed from chiller. Traces of vapor should be dis-

WARNING

WAR NING

DO NOT REUSE disposable (nonreturnable) cylinders or attempt to refill them. It
is DANGEROUS AND IL LEGAL. W hen cylinder is emptie d, evacuat e remaining
gas pressure, loosen th e collar , an d unscr ew and discard t he valve stem. DO
NOT INCINERATE.

CHECK THE REFRIGERANT TYPE before adding refrigerant to the machine. The
introduction of the wrong refrigerant can cause machine damage or malfunction
to this machine. Operation of this equipment with refrigerants other than those
cited herein shou ld comp ly with ANS I/ASHRAE - 15 (latest ed ition). Con t act Car­rier for further information on use of this machine with other refrigerants.

DO NOT ATTEMPT TO REMOVE fittings, covers, etc., while machine is under
pressure or while machine is running. Be sure pressure is at 0 psig (0 kPa)
before breakin g an y refrigeran t connec t io n.

CAREFULLY INSPECT all relief devices, rupture discs, and other relief devices
AT L E AS T ONCE A YEAR. If machine op erates i n a co rrosive atmo sphere,
in spect th e devices at mor e f requen t in t ervals.

DO NOT ATTEMPT TO REPAIR OR RECONDITION any relief device when corro­sion or build-up of foreign material (rust, dirt, scale, etc.) is found within the
val ve body o r mechani sm. Re pl ace the device.

DO NOT install relief devices in series or backwards.
USE CARE when working near or in line with a compressed spring. Sudden

release of t he spri ng can cause it and o bj ects in its path to act as proj ect iles.

!

WARNING

CAUTION

DO NOT STEP on refrigerant lines. Broken lines can whip about and release
refrigerant, causing personal injury.

DO NOT climb over a machine. Use platform, catwalk, or staging. Follow safe
practices when using ladders.

USE MECHANICAL EQUIPMENT (crane, hoist, etc.) to lift or move inspection
cov ers or ot her heavy component s. Even if compon ents ar e li ght, us e mecha ni ­cal equipment when there is a risk of slipping or losing your balance.

BE AWARE tha t cert ain au t omati c st art arrangem ents CAN ENGAGE THE
STARTER, TOWER FAN, OR PUMPS. Open the disconnect
tower fan, and pumps.

USE only repair or replacement parts that meet the code requirements of the
original equipment.

DO NO T VE N T OR DR A IN wa te rb ox es c on t ai nin g industr ia l brine s, liq uid, gas e s,
or semisolids without the permission of your process control group.

DO NOT LOOSEN waterbox cover bolts until the waterbox has been completely
drained.

DOUBLE-CHECK that coupling nut wrenches, dial indicators, or other items
hav e been removed b ef ore rot at ing any shafts.

DO NOT LOOSEN a packing gland nut before checking that the nut has a posi­tive thread engagement.

!

CAUTION

ahead of

the st arter,

CAUTION

PERIODICALLY INSPECT all valves, fittings, and piping for corrosion, rust,
leaks , o r damage.

PROV IDE A DRAIN conne ct ion in the vent lin e near each pressure rel ief de vice
to prevent a build-up of condensate or rain water.

!

CAUTION

Contents

List of Tables
List of Figures
Safety Considerations
Introduction
Abbreviations and Explanations
Machine Familiarization

Machine Information Plate
System Components
Cooler
Condenser
Moto r-Co m pr e ss o r
Control Center
Factory-Mounte d Starte r (O ptional)
Storage Vessel (Optional)

Contents

Refrigeration Cycle
Motor/Oil Ref r ige r ati on Co oling Cyc le
Lubrication Cycle

Summary
Details
Oil Reclaim System

During Normal Machine Operation
During Light Load Conditions

Starting Equipment

Unit Mounted Solid-State S tarter (Optional)
Unit Mounted Wye-Delta Starter (Optional)

Controls

Definitions

Analog Signal

Digit al Signal
Volatile Memory

General
PIC System Components

Pr ocessor Modu le (PSIO)
Starter Management Module (SMM)
Local I nter f ace Devi ce (LID)
6-Pack Relay Board
8-Input Modules
Oil Heater Contactor (1C)
Oil Pump Contactor (2C)
Hot Gas Bypa ss Contactor Relay (3C) (Optional )
Control Transformers (T1-T4)

Contents

Control and Oil Heater Volt age Sel ecto r (S1)

LID Operation and Menus

General
Alarm and Alerts

Menu Structure
To View Point Sta tus
Override Operations
Time Schedule Operation
To View and C hange Set Point s
Service Operation

PIC System Funct ions

Capacity Control
Enteri ng Chilled Water Control
Deadband
Proportional Bands and Gain
Dema nd Limiting
Machine Timers

Contents

Occupancy Schedule

Safety Controls

Shunt Trip

Contents

Def a u lt Scr een Fr eeze
Motor Cooling Control
Ramp Loading Control
Capacity Ov erride
High Discharge Temperature Cont r ol
Oil Sump Temperature Control

PSIO Softwa r e Vers ions 08 and Lower
PSIO Software Versions 09 and Hi gher

Oil Cooler
Remote Start/ St op Contr ol s
Spare Safety Inputs

Spare Alarm C ont acts

Condenser Pump Control
Condenser Freeze Pr ote ction

Contents

Tower Fan Relay
Auto. Restart After Power Failur e
Water/Br ine Reset
Demand Limit Control, Option (Requires Optional 8- Input Module)
Surge Prevention Algor ithm
Surge Protection
Lead/Lag Control

Common Point Sensor Installation
Machi ne Communication Wiri ng
Lead/Lag Operation
Faulted Chiller Operation
Load Balancing
Auto Restart After Power Failure

Ice Build Control

Ice Build Initiation

Contents

Start-Up/Recycle Operation
Tempe rature Control During Ice Build
Termination of Ice Build
Retu rn to Non-i ce Build Operati ons

Attach to Network De vi ce Control

Changing Refrigerant Types
Attachi ng to Other CC N Modul es

Service Operation

To Log On
To Log Off
Holida y Scheduling

Start-Up/Shutdown/Recycle Sequence

Local Start-Up
Shutdown Sequence
Automatic Soft-S top Am ps Threshold (PSIO Sof tw are Version 09 and

Higher)

Chilled Water Recycle Mode
Safety Shutdown

Before Initial Start-Up

Job Data Required
Equipment Requi r ed
Using the Optional Storage Ta nk and Pumpout System
Remove Shipping Packaging
Open Oil Circuit Valves
Torque All Gasketed Joints
Check Machine Tightness
Ref rigerant T racer

Contents

Leak Test Machine
Standing Vacuum Te st

Contents

Machine Dehydration
Inspect Water Piping
Check Optional Pumpout Compre ssor Water Piping
Check Relief Devices
Inspect Wiring
Carrie r Comfort Network Interface
Check Starter

Mechanical-Type Starters
Benshaw, Inc. Solid-State Starter
Cutler-Hammer® Solid-State Starters

Oil Charge
Power Up the Controls and Check the Oil Heater

Softwa re Ver sio n

Set Up Machine Control Configurat ion
Input the Design Set P oi n ts

Contents

Input the Local Occupied Schedule (OCCPC01S)
Selecting Refrigerant Type

To Confirm Refrigerant Type
To Chang e Re frigerant Type

Input Service Configurations

Password
Input Time and Date
Change LID Configuration If Necessary
Modify Controller Identificati on If Necessary
Input Equipment Service Par ameters If Necessary
Modify Equipment Configuration If Necessary
Check V oltage Supply
Perform an Automated Control Test

Check Optional Pumpout System Controls and Compressor
High Altitude Loca ti ons

Charg e Refrig er ant into Mach ine

19XL Mach ine E quali z at ion without Pumpout Uni t
19XL Mach ine E quali z at ion with Pumpout Unit
Trimmi ng Refrigerant Charge

Initial Start-Up

Preparation
Manual Operation of th e Guid e Vane s
Dry Run to Test Start-Up Sequence
Check Rotation

If Rotation Is Proper
If the Motor Rotation Is Not Clockwise
Notes o n Solid- State Starter s (Bens haw, Inc.)

Contents

Check Oil Pressure and Compressor Stop
Calibrate Motor Current Demand Setting
To Prevent Accidental Start-Up

Contents

Check Machine Operating Condition
Instruct the Customer Operator

Cool er-Condenser
Option al Stor age Tank and Pumpout System
Motor Compressor Assembly
Motor Compressor Lubrication Sys te m
Control System
Auxiliary Equ ipment
Describe Machine Cycles
Review Maintenance
Safety Devices and Procedures
Check Operator Know ledge
Review the Start-Up, Operation, and Maintenance Manual

Operating Ins tr uc t ion s

Operator Duties

Contents

Prepare the Machine for Start-Up
To Star t th e M achine
Check the Runni ng System
To Stop the Machine
After Limited Shutdow n
Extended Shutdown
After Extende d Shut down
Cold Weather Operation
Manual Guide Vane Operation
Refrigera ti on Log

Pump out and Ref rigerant Transf er Procedures

Pr eparation
Operating the Optional Pumpout Compressor

To Read Re frige ran t Pressur es

Machines with Storage Tanks

Transfer Refri gerant from Storag e Tank to Mach ine
Transfer the Refrigerant from Machine to Storage Tank

Machines with Isolation Valves

Transfer All Refrigerant to Condenser Vessel
Transfer All Refrigerant to Cooler/Compressor Vessel

Retu rn Refrigeran t to Normal Operating Conditions

Genera l Mai nt e na nc e

Refrigeran t Pro perties
Adding Refri gera n t
Removing Refrigerant
Adjustin g the Refr igeran t Charge

Contents

Ref rigeran t Leak T est in g
Le ak Ra te

Test After Service, Repair, or Major Le ak

Ref rigerant Tracer
To Pres surize w ith Dry Nitr ogen

Repair the Leak, Retest, and Apply S tanding Vacuum Test
Checking Guide Vane Link age

Checki ng the Auxiliary S witch on Gu ide Vane Actua t or

Trim Refrigerant Charge

Weekly Maintenance

Check the Lubrication System

Sched ule d Mai nt e na nc e

Service Ontime
Inspect th e Co ntro l Cen ter

Contents

Check Safety and O perating Controls Monthly
Changing Oil Filter
Oil Specification

Contents

Oil Changes

To Change the Oil

Refrigeran t F ilter
Oil Reclaim Filters
Inspect Refrigerant Float System
Inspect Relief Valves and Piping
Com pr e sso r Be aring and Gear Ma in t en ance
Inspect the Hea t Exchanger Tubes

Cooler
Condenser

Water Leaks
Water Tre atment
Inspect the Starting Equipment
Check Pressure Transducers

Optional Pumpout System Maintenance

Optional Pumpout Compressor Oil Charge
Option al Pu mp out S af ety Control Settings

Ordering Replacement Chiller Parts

Troub le sh ooting Gui de

Overvi ew
Checking the Display Messages
Checking Tem per a t ur e Sen sor s

Resistance Check
Voltage Drop
Check Sensor Ac cura cy
Dual Tempe r ature Sensors

Contents

Checking Pressure Transducers

Transducer Replacement

Control Algori thms Checkout Procedure

Contents

Control Test
Control Modu les

Red LED
Green LE Ds

Notes on Module Operation
Processor Module (PSIO)

Inputs
Outputs

Starter Management Modul e ( SM M)

Inputs
Outputs

Options Modules (8-Input)
Replacing Defective Processor Modules

Installation

Solid-State Starters

Testing Silicon Control Rectifiers in Benshaw, Inc. Solid-State Starters

Contents

Testing Silicon Control Rectifiers (SCRs) in Cutler-Hammer®
Solid-State Starters

Electronic Protection Relay (EPR)

Physical Data

Initial Start-Up Checklist for 19XL Hermetic Centrifugal Liquid Chiller

List of Tables

Table 1 — Major PIC Components and Panel Locations
Table 2 — LID Screens

Example 1 — Status01 Disp lay Scr een
Example 2 — Status02 Disp lay Scr een
Example 3 — Status03 Disp lay Scr een
Example 4 — Setpoint Display Screen
Example 5 — Confi gur ation (Config) Dis p l ay Scr ee n
Example 6 — Le ad/Lag Confi guration Display Screen
Example 7 — Service1 Display Screen
Example 8 — Service2 Display Screen
Example 9 — Service3 Display Screen
Example 10 — Mainten ance (Maint0 1) Display Scr een

Contents

Example 11 — Mainten ance (Maint0 2) Display Scr een
Example 12 — Mainten ance (Maint0 3) Display Scr een
Example 13 — Mainten ance (Maint0 4) Display Scr een

Contents

Table 3 —

Protective Safety Li m it s and Control Settings

Table 4 — Capacity O ver rides
Table 5A — HCFC-22 Pressure — Temperature (F)
Table 5B — HCFC-22 Pressure — Temperature (C)
Table 5C — H FC-134a Pressure
Table 5D — H FC-134a Pressure

Te m p e r a ture (F )

—

Te m p e r a ture (C)

—

Table 6 — Potentiometer Adjustme nt
Table 7 — Amps Corre ction Fa ctors for 19XL Motors
Table 8 — Control Test Menu Functions
Table 9 — Refrigerant (HCFC-22 or HFC-134a) Charges
Table 10 — LID Primar y an d Seconda r y Messages and Custom Alarm/

Alert Messages with Troublesho oting Guides

A. Shutdown with On/Off/Reset-Off
B. Timing Out or Ti m ed Out
C. In Recycle Shutdown

Contents

Table 10 — LID Primary an d Seconda r y Messages and Custom Alarm/

Alert Messages with Troublesho oting Guides (Continued)

D. Pre-Start Alerts
E. Normal or Auto.-Restart
F. Sta r t-Up Failures
G. Compressor Jumpstart and Refrigerant Protection
H. Nor mal Run with Reset, Tempe r ature, or Demand
I. Normal Run Overrides Active (Alerts)
J. Out-Of-R ange Sensor Failures
K. Machine Pr otect Limit Faults
L. Machine Alerts
M. Spare Sensor Alert Messages
N. Other Problems/Malfunctions

Table 11A—Thermi stor Temperature (F) v s Resistance/Volta ge Drop
Table 11B—Thermi stor Temperature (C) vs Re sistance/Voltage Drop
Table 12 — Benshaw, Inc. Solid-State Starter Tr oubl es hooting Guide

Contents

Table 13 — Cutler- Hamme r® S olid-State Starter Troubl eshooting

Guide
Table 14 — Heat Exchanger Data
Table 15 — Additional Data for Marine Waterboxes
Table 16 — Compressor Wei ghts
Table 17 — Compressor/Motor Weights
Table 18 — Waterbox Cove r We ights
Table 19 — Optional Pum pout System Electr ica l D ata

List of Figures

Figure 1 — 19XL Iden tification
Figure 2A— Typi cal 19XL Components — Design I
Figure 2B— Typi ca l 19 XL Components — Design II
Figure 3 — Refrigera nt Moto r Cooling an d Oil Cooling Cycles
Figure 4 — Lubricat i on System
Figure 5 — Cutler-Hammer Soli d -State Starter, Internal Vi ew
Figure 6 — Benshaw, Inc. Solid-State Starter, Internal View
Figure 7 — Typical St arte r Fr ont View (Solid-S ta te Starter Shown)
Figure 8 — 19XL Contr ols and Sensor Locations
Figure 9 — Control Sensors (Temperature)

Contents

Figure 10— Control Senso rs (Pr essure Tr ans ducer, Typical)
Figure 11— Control Panel (Front View), with Options Module
Figure 12— Power Panel with Options

Contents

Figure 13— LID Defa ult Screen
Figure 14— LID Service Screen
Figure 15— Example of Point Status Screen (Status01)
Figure 16— 19XL Menu Structur e
Figure 17— 19XL Service Menu Structure
Figure 18— Example of Time Schedule Operation Screen
Figure 19— Exam pl e of Set Poi nt Screen
Figure 20— 19XL Hot Gas Bypass/Surge Preve nti on
Figure 21— 19XL with Default Metric Settings
Figure 22— Example of Att ach to Net wo rk D evice Screen
Figure 23— Example of Holiday Period Screen
Figure 24— Control Seque nce
Figure 25— Typical Wet-Bulb Ty pe Vacuum Indicator
Figure 26— 19XL Leak Test Proce dur es

Contents

Figure 27— Typical Opti onal P ump out S ys te m Pipi ng Schematic with

Storage Tank
Figure 28— Typical Opti onal P ump out S ys te m Pipi ng Schematic with-

out Storage Tank
Figure 29— Dehydration Cold Trap
Figure 30— Benshaw, I nc. Solid-State Starter Power St ack
Figure 31— Ramp Up and Starting Torque Potentiometers
Figure 32— Typical Potent iometer Adjustment
Figure 33— Typ ica l Cut le r-Hammer® Sol id-State St arter
Figure 34— Cor rect Motor Ro tat ion
Figure 35— Refrigerat ion Log
Figure 36— 19XL Pumpout Unit W iring S che m at ic
Figure 37— Optional Pumpout System
Figure 38— Guide Vane Actua tor Li nka ge
Figure 39— 19XL Float Val ve Des igns

Contents

Figure 40— Optional Pumpout System Controls
Figure 41— PSIO Module Address Selector Switch Locations and LED

Locations
Figure 42— LID Module (Rear View) and LED Locations
Figure 43— Processor (PS IO) Module
Figure 44— Starter Manage ment Module (SSM)
Figure 45— Options Module
Figure 46— Typical Benshaw, Inc. Solid-State Starter (Internal View)
Figure 47— Resistance Check
Figure 48— SCR and Power Poles
Figure 49— Typ ica l Cut le r-Hammer® Sol id-State St arter (Intern al

View)
Figure 50— Cutler-Hammer Terminal Functions
Figure 51— Solid-State Starter, General Operation Tr oubl eshooting

Guide (Typi cal)

Contents

Figure 52— Solid-State Sta rter, S tarter F ault (Mo tor Will Not Start)

Troubleshooting Guide (Typical )
Figure 53— Compressor Fi ts and Clearances
Figure 54— Compressor Fits and Clearances (Continue d)
Figure 55— Compressor Fits and Clearances (Continue d)
Figure 56— Electronic PIC Controls Wiring Schematic
Figure 57— Machine Power Panel, Starter Assembly, and Motor Wir-

ing Schemat i c
Figure 58— Typical Wye-D elta Uni t Mounted Starter Wiring Schem at ic

Introduction

Prior to initial star t-up of the 19XL unit, tho s e inv olved in the s tart-up , opera tion, and
maintenance should be thoroughly familiar with these instructions and other necessary job data.
This book is outlined so that you may b ecome familiar w ith the control system be fore performing
start-up procedures. Procedures in this manual are arranged in the sequence required for
proper m ac hine start- up and operation.

WARNING

This unit us es a m ic r opr oc e ss or co nt r ol sy s tem . Do not short or jumper betwe en
terminations on circuit boards or modules; control or board failure may result.

Be aware of electrostatic discharge (static electricity) when handling or making
contact with circuit boards or module connections. Always touch a chassis
(grounded) part to dissipate body electrostatic charge before working inside
con t rol center.

Use extreme care when handling tools near boards and when connecting or dis­connecting terminal plugs. Circuit boards can easily be damaged. Always hold
boards by the edges and avoid touching components and connections.

This equipment uses, and can radiat e, radi o freq uency en ergy. If n ot inst alled
and used in accordance with the instruction manual, it may cause interference to
rad io co mm un ic ations. I t ha s be en te ste d a nd fou nd to com ply wi t h the limits f or
a Clas s A computing device pursuan t to S ub part J o f Part 15 of FCC Rul es,
which are designed to provide reasonable protection against such interference
when o perated in a commercial envi ronmen t . O perati on of thi s equip ment in a
residential area is likely to cause interference, in which case the user, at his own
expe nse, wi ll be required to ta ke whate ver meas ures may be requi red to correct
the in t erference.

Alw ays stor e and transport replacement or defe ct ive boa rds in ant i-stat ic ship­ping ba g.

!

WARNING

Abbreviations and Explanations

Frequently us ed abb r ev iatio ns in this manual inc lude:

CCN — Carrier Comfort Network LID — Local Interface Device
CCW — Countercloc kwi se LCW — Leaving Chill ed Water
CW — Clockwise OLTA — Overload Trip Amps
ECW — Entering Chi ll ed W ate r PIC — Product Integr at ed Cont r ol
ECDW — En teri ng Condenser Water PSIO — Processor Sensor Input/Out put Module
EMS — Energy Manag eme nt Sys tem RLA — Rated Load Amps
HGBP — Hot Gas Bypass SCR — Silicon Control Rectifier
I/O — I nput/Output SI — Inter nat ional System of Units
LCD — Liquid Crystal Display SMM — Starter Management Module
LCDW — Leaving Condenser Water TXV — Thermal Expansion Valve
LED — Light-E m itti ng Di ode

The 19XL machines use HCFC-2 2 and HFC - 134a ref r igerant. Whe n r eferen c ing refrigerant
charg es in this manual , t he HCFC - 22 c harge will be lis ted fir s t and the HF C- 134a va lue will be
show n nex t to it in [ ].

Words printed in all capital letters or in italics may be viewed on the LID.

The PSIO s oftwar e v er s ion nu mb er of your 19X L unit will be lo c ated on the front cover.

Machine Familiarization

Figure 1

(

Machin e Information Plate

The infor m ati on plate is loc ate d on the rig ht side of the machine control ce nter panel.

Click here for Figure 1 — 19XL Identification

System Components

The components include the cooler and condenser heat exchangers in separate vessels,
motor-compressor, lubrication package, control center, and motor starter. All connections from
pressure vessels have external threads to enable each component to be pressure tested with a
threaded pipe cap during factory assembly.

Cooler

This ves s el (als o k nown as th e ev aporator) is locat ed underneath the compress or . The
cool er is m aintained at lower temperat ur e/pr es s ur e so tha t evaporating r efrig er ant can remove

, Figur e 2A ( Front View) (Rear View), and Figure 2B (Front View) (Rear View)

heat fr om water f lowing through its internal tubes.

Condenser

The condenser operates at a highe r temperat ur e/pr es s ur e tha n the cool er , and has water

flowing through its internal tubes in order to remove heat from th e r efrigerant.

Moto r-Co m pr essor

This component maintains system temperature/pressure differences and moves the heat
carrying refrigerant from the cooler to the condenser.

Control Center

The control center is the user interface for controlling the machine. It regulates the machine’s
capac ity as re quired t o m aintain pr oper leaving chilled water tem per atu r e. The control center :

• registers cooler, condenser, and lubricating system pressures

• shows machine operating condition and alarm shutdown conditions

• recor ds the tot al machine ope r ating hour s

• sequences machine start, stop, and recycle under microprocessor control

• provides access to other CCN (Carrier Comfort Network) devices

Factory-Mounte d Starte r (O ptional)

The sta r ter allows for the proper starting and disconnecting of t he elect r ic al energy for t he
compressor-motor, oil pump, oil heater, and control panels.

Storage Vessel (Optional)

There are 2 sizes of storage vessels available. The vessels have double relief valves, a
magnetically coupled dial-type refr igerant leve l gage, a one- inch FPT dra in v alve, and a 1/2-in.
male flare vapor connecti on for th e pum pout unit. A 30- in.-0 - 400 psi (–101- 0-2750 kP a) gage

also is su pplied with each unit.
Note: If a storage vessel is not used at the jobsite, factory-installed isolation valves on the

chil ler m ay be used t o is olate the machine charge in either t he c ooler or c onden s er . An
optional pumpout compressor system is used to transfer refrigerant from vessel to ves­sel.

Refrig eration Cycle

The compressor continuously draws refrigerant vapor from the cooler, at a rate set by the
amount of guide vane opening. As the compressor suction reduces the pressure in the cooler,
the remaining refr igerant boils at a fairly low temperatur e (typically 38 to 42 F [ 3 to 6 C]). Th e
energy r equired for bo iling is obtained fro m the water flowi ng throu gh the cooler tubes. With
heat en er gy r em oved, the wat er becomes c old enough for us e in an air conditioning circ uit or
process liquid cooling.

After taking heat from the water, the refrigerant vapor is compressed. Compression adds still
more heat energy and the refrigerant is quite warm (typically 98 to 102 F [37 to 40 C]) when it is
discharged from the compressor into the condenser.

Relativel y co ol ( typically 65 t o 90 F [18 to 32 C]) water flowin g into the conden s er tubes
removes heat from the re frigerant and the vap or c ondenses to li quid.

The liq uid refrigerant pass es through orific es into the FL A S C ( Flash Subcooler) cham ber

(Figure 3). Since the FLASC chamber is at a lower pressure, part of the liquid refrigerant flashes
to vapor, thereby cooling the remaining liquid. The FLASC vapor is recondensed on the tubes
whic h are c oo led by ent ering condense r wat er. The liquid dra ins in to a flo at ch amber bet wee n
the FLASC chamber and cooler. Here a float valve forms a liquid seal to keep FLASC chamber
vapor from ente r ing the co oler. When liquid refr igerant pas s es throug h the valve, some of it
flashes to vapor in the reduced pressure on the cooler side. In flashing, it removes heat from the
remaining liquid . T he r efrigeran t is now at a temperature and pr essur e at whi c h the cycle
began.

Motor/Oil Refrigeration Cooling Cycle

The motor and the lubricating oil are cooled by liquid refrigerant taken from the bottom of the
condenser vessel (Figure 3). Flow of refrigerant is maintained by the pressure differential that
exist s due to compress or oper ation. After the refrigerant flows past an isolation valve, an in-line
filter, and a sight glass/moisture indicator, the flow is split between motor cooling and oil cooling
systems.

Flow t o th e m otor fl ows throug h an orifi c e and int o the motor . Ther e is als o another orifice
and a solenoid valve which wi ll open if additional mot or c ooling is required . O nc e past t he
orific e, the refrig er ant is direct ed ov er the mo tor by a spr ay noz z le. The refri ger ant co llects in
the bottom of the motor casing and then is drained back into the cooler through the motor
refrigerant drain line. A back pressure valve or an orifice in this line maintains a higher pressure

in the motor shell than in the c ooler/ oil sump. The mo tor is protected by a temperatur e s ensor
imbedded in t he s tator windings. Higher motor te m per atur es ( above 125 F [51 C] ) ener gize a
solenoid to pr ov ide add itional m otor coolin g. A furt her increas e in tem per atur e pas t the m otor
override set point will over r ide the temperatur e c apacit y co ntrol to hold, and if the motor
temperatu r e r is es 10° F (5.5° C) ab ov e this set point , will close the inlet guide vanes. If the
temperatu r e r is es above t he s afety lim it, th e c om pr essor will shut down.

Refrigerant that flows to the oil cooling system is regulated by a thermostatic expansion
valve . T her e is always a mi nim um flo w by pass ing the TXV , which flows th r ough an orifice. The
TXV valve regulates flow into the oil/refrigerant plate an d frame-type he at exchanger. The bulb
for the expansion valve controls oil temperature to the bearings. The refrigerant leaving the heat
exchanger then returns to the cooler.

Click here for Figure 2A (Front and Rear Views) — Typical 19XL Components —
Design I

Click here for Figure 2B (Front and Rear Views) — Typical 19XL Components —
Design II

Click here for Figure 3 — Refrigerant Motor Coolin g and Oil Co oling Cycles

Lubr ic ati on Cy c le

Su mma ry

The oil pump, oil filter, and oil cooler make up a package located partially in the transmission
casting of the compressor-motor assembly. The oil is pumped into a filter assembly to remove
foreign part ic les, and is then forc ed into an oil cooler he at exchanger where t he oil is cooled to
proper operational temperatures. After the oil cooler, part of the flow is directed to the gears and
the hig h s peed shaft bearings; the rem ainin g flow is direct ed to the motor shaft bearings. Oil
drains into the transmission oil sump to complete the cycle (Figure 4).

Details

Oil is charged into the lubrication system through a hand valve. Two sight glasses in the oil
reserv oir perm it oil lev el observation. Normal oil level is bet ween the m iddle of t he upper sight
glass and the top of the lower sight glas s when the c om pr ess or is s hut down. The oil level
should be visible in at least one of the 2 sight glasses during operation. Oil sump temperature is
displayed on the LID default screen. Oil sump temperature ranges during compressor operation
betwe en 100 to 120 F (37 to 49 C) [120 to 140 F (49 to 60 C) ].

The oil pu m p s uc tion is fed from the oil r es er v oir. An oil pr es s ure r elief va lv e m aintains 18 to
25 psid (124 to 172 kPad) differential pressure in the system at the pump discharge. This
differential pressure can be read directly from the Local Interface Device (LID) default screen.
The oil pump discharges oil to the oil filter assembly. This filter is capable of being valved closed
to permit removal of the filter without draining the entire oil system (see Maintenance sections
for details). The oil is then piped to the oil cooler. This heat exchanger uses refrigerant from the
condenser as the coolant. The refrigerant cools the oil to a temperature between 100 and 120 F
(37 to 49 C) .

As the oi l leav es the oi l co oler, it pas s es the oil pre s s ur e transducer and the therm al bulb for
the refrigerant expansion valve on the oil cooler. The oil is then divided, with a portion flowing to
the thr us t bearing, fo r war d pini on bearing, and gear spr ay . The balance then lubricates the
motor s haft bearings and the r ear pinio n bearing. The oil temper atur e is m eas ured as the oil
leaves the thr us t and forward journal beari ngs with in the bear ing hou s ing. The oil then dr ains
into the oil reservoir at the base of the compressor. The PIC (Product Integrated Control)
measures the temperature of the oil in the sump and maintains the temperature during
shutdown (see Oil Sump Temperature Control sec tion ) . T his tempe r ature is r ead on the LID
default screen.

Duri ng the machine star t-up, the PIC will energize t he oil pump and pro v ide 15 sec onds of
prel ubr icat ion to the bearings after press ur e is ve r ified before st ar ting the compres s or. Du r ing
shutdown, the oil pump will run for 60 seconds after the compressor shuts down for the purpose

of post-lubrication. The oil pump can also be energized for testing purposes in the Control Test.

Ramp loading can slow the rate of guide vane opening to minimize oil foam ing at star t-up. If
the guide vanes open quickly, the sudden drop in suction pressure can cause any refrigerant in
the oil to f las h. The r es ulting oil foam c annot be pumped efficiently , therefore oil pre s s ur e falls
off and lubric ation is poor . If oil pressur e falls below 15 psid (103 kPad) differ ential, the PIC will
shut down the compressor.

Clic k here for Figure 4 — Lubr ication System

Oil Reclaim System

The oil reclaim system operates to return oil back to the oil reservoir by recovering it from 2
areas on the machine. The primary ar ea of recovery is from the guide vane housing. Oil als o is
recovered, along wi th refrigera nt, from the cooler.

Any refrige r ant that enters the oil re s er v oir /trans m iss ion area is flash ed into gas . The
demister line at the top of the casing will vent this refrigerant into the suction of the compressor.
Oil ent r ained in the refr igerant is eli m inated by the demister filter.

During Normal Machine Operation

compressor pulls th e r efrigerant into the guide va ne housing to be com pr ess ed, the oil will
normally drop out at this point and fall to the bottom of the housing where it accumulates. Using

, oil is entra ined with the ref r igerant. As the

disch ar ge gas pr es s ure to power an educto r , t he oil is vac uumed f r om the hou s ing by the
eductor and is discharged into the oil reservoir. Oil and refrigerant are also recovered from the
top of the cooler refrigera nt level and are dis c harged into the guide v ane hou s ing. The oil wil l
drop to the bottom of the guide vane housing and be recovered by the eductor system.

Duri ng Lig ht Load Conditions

enough velocity to r eturn oil, which is flo ating in the cool er bac k to the com pr ess or . In addit ion,
the edu c tor may not have en ough pow er to pull the oil from the guide v ane hou s ing back into
the oil re s er v oir due to extr em ely low pr essur e at the guide vanes. Two solen oids, located on
the oil re c laim piping, ar e operated so that the ed uc tor can pull oi l and refrigerant direc tly fr om
the cooler and discharge t he m ix ture into the oil reser v oir. The oil reclaim s olenoi ds ar e
operated by an auxil iar y c ontac t integr al to the guide va ne ac tua tor. This s witch ov er of the
solenoids oc c ur s when the guide vanes are open ed beyond 30 deg r ees from th e c los ed
posi tion.

, the suction gas into the compres s or does not hav e

Starting Equipment

The 19XL requires a motor starter to operate the centrifugal hermetic compressor motor, the
oil pump, and va r ious auxiliary equipment. The star ter serv es as the main f ield wiring interfa c e
for the contractor.

Three t y pes of sta r ters are av ailab le from Car r ier Corporation: solid-state, wye-delta, and
across-the-line starters. See Carrier Specification Z-375 for specific starter requirements. All
starters mu s t meet these specifications in order to properly start and s atisfy m ec hanical saf ety
requir em ent s . Starter s m ay be s upplied as separate, fre e- s tanding units , or may be m ounted
direc tly on th e c hiller (unit mounted ) for low-volta ge units only .

Inside the star ter are 3 separate ci r c uit brea ke r s . Circuit br eaker CB 1 is the compress or
motor circuit breaker. The disconnect switch on the starter front cover is connected to this
breaker. Circuit breaker CB1 supplies power to the compressor motor.

WARNING

The main circuit br eaker (CB1) on t he front of t he starter disconn ects the main
motor current only. Power is still energized f or the other circuits. Two more cir­cuit breakers inside the starter must be turned off to disconnect power to the oil
pump, PIC controls, and oil heater.

!

WARNING

Circu it breaker CB2 su pplies power t o the contr ol center, oil heater , and po r tions of the
starter controls. Cir c uit break er CB 3 s upplie s power to oi l pum p. Bot h of these c ir c uit br eak ers
are wi r ed in parallel with CB1 so that power is s upplie d to them if t he CB 1 disconnect is ope n.

All starters are shipped with a Carrier control module called the Starter Management Module
(SMM). This module controls and monitors all aspects of the starter. See the Controls section
for additional SMM information. All starter replacement parts are supplied by the starter
manufacturer.

Unit-Mounted S olid-State Starter (Optiona l)

The 19XL may be equipped with a solid-state, reduced-voltage starter (Figu r e 5, Figure 6,

Figure 7). This starter provides on-off control of the compressor motor as its primary function.

Using this type of starter reduces the peak starting torque, reduces the motor inrush current,
and decr eases m ec hanical shock. This is s um m ed up by th e phr ase ‘‘soft s tarting.’’

Two var ieties of solid-state s tarter s ar e av aila ble as a 19X L option ( factor y s upplied and
installed ) . W hen a unit- m ounted, optional , solid-s tate start er is pur c hased with th e 19X L, ei th er
a Bensh aw, Inc . or Cutler - Hamm er ® so lid-s tate starter wi ll be shipped wi th the unit . See

Figure 5 and Figure 6. The solid-state starter’s manufacturer name will be located inside the

starter access door. See Figure 7.

These starte r s oper ate by reducin g the start ing volt age. The start ing torq ue of a motor at full
voltage is typically 125% to 175% of the running torque. When the voltage and the current are

reduc ed at sta r t-up, the start ing tor que is reduc ed as well. The objec t is to redu c e the sta r ting
voltage to jus t the voltage nec es s ary to develo p the torque required t o get the motor mov ing.
The voltage and current are then ramped up in a desired period of time. The voltage is reduced
through the use of silicon controlled rectifiers (SCR). Once full voltage is reached, a bypass
contac tor is energi z ed to bypass the SC Rs .

WARNING

When voltage is supplied to the solid-state circuitry, the heat sinks within the
start er are at line voltag e. Do not to uch the he at sinks wh ile volt age is pr esent o r
serious injury will result.

There are a number of LEDs (light - em itting dio des ) that ar e us eful in troub les hoot ing and
starter chec k out on Be ns haw, Inc. solid-st ate sta r te r s . T hes e are us ed to indic ate:

• voltage to the SCRs

• SCR contro l v oltage

• pow er indicat ion

• proper phasing for rotation

• start circuit energized

• overtemperature

• grou nd faul t

!

WARNING

• curr ent unbalance

• run state

These LEDs are further explained in the Check Starter and Troubleshooting Guide sections.

Unit-Mounted Wy e-Delta Start er (Optional)

The 19XL machine may be equipped with a wye-delta starter mounted on the unit. This
starter is intended for use with low- v oltage m otors ( under 600 v). It reduc es the starting curr ent
inrus h by c onnecting eac h phase of the mot or windin gs into a wye co nfigu r ation. T his oc c urs
duri ng the star ting per iod when the motor is acc elerating up to spee d. After a time del ay , once
the mot or is up to speed, the star ter automatical ly c onnects the phas e wind ings into a delta
configurat ion.

Click here for Figure 5 — Cutler-Hammer® Solid-State Starter, Internal View

Click here for Figure 6 — Benshaw, Inc. Solid-State Starter, Internal View

Click here for Figure 7 — Typical Starter Front View (Solid-State Starter Shown)

Definitions

Analog Signal

Controls

An ana log signal

operating limits. (Example: A temperature sensor is an analog device because its resistance
changes in proporti on to the te m per atu r e, gener ating ma ny v alues.)

Digit al Signal

A digital (discrete) signal

(Example: A switch is a digital device because it only indicates whether a value is above or
below a s et point or boun dar y by generating an on/off, high/low, or open/closed signal.)

Volatile Memory

Vola tile memory

restored.

CAUTI ON CAUTION

The memory of the PSIO and LID modules are volatile. If the battery in a module
is removed or damaged, all programming will be lost.

varie s in pr oportion to t he m onit or ed sourc e. It qua ntifies v alues bet ween

is a 2-position representation of the value of a monitored source.

is memory inc apabl e of bein g s us tained if power is los t and su bs equen tly

!

General

The 19XL hermetic centri fu gal liquid chil ler c onta ins a m ic r oprocessor - based c ontro l c enter
that monitors and controls all operations of the machine. The microprocessor control system
matc hes the coo ling capacity of the machine to the co oling load while pr oviding st ate-of- the-art
machine protection. The system controls cooling load within the set point plus the deadband by
sensing the leaving chilled water or brine temperature, and regulating the inlet guide vane via a
mecha nic ally linked actuator motor. The guid e v ane is a var iable flow prewhirl ass embly that
contr ols the re frigeration effect in the cooler by r egulating the am ount of refrig er ant vap or flow
into t he c om press or . An increase in guid e v ane open ing increases c apacit y . A dec r ease in
guide vane opening decreases capacity. Machine protection is provided by the processor which
moni to r s the digi tal and analog in puts and execut es c apacit y ov er r ides or s afety s hutdo wns , if
requir ed.

PIC System Components

The Product Integrated C ontrol (PIC) is the control system on the machine. See Table 1. The
PIC controls the oper atio n of the mac hine by monito r ing all op er ating c ondit ions. The P IC can
diagnose a problem and let th e operator know what the prob lem is and wha t t o c hec k . It
promp tly positions the gui de v anes to ma intain leaving chilled water temp er ature. It can
interface with auxiliary equipment such as pumps and cooling tower fans to turn them on only
when required. It continually checks all safeties to prevent any unsafe operating condition. It

also regulates the oil heater while the compressor is off, and the hot gas bypass valve, if
installed.

The PIC ca n be inte r faced wi th the Carr ier Comfort Network (CCN) if desired. It can
communicat e with other PIC-equ ipped chille r s and other CCN devices .

The PIC consists of 3 modules housed inside the 3 major components. The component
names and the contr ol v oltage cont ained in each compon ent are listed below (als o s ee Table 1):

• control center
– all extra low-voltage wiring (24 v or less)

• pow er panel
– 230 or 115 v control voltage (per job requirement)

– up t o 600 v for oil pump power

• starter cabinet
– mac hine power wi r ing (per job requirement)

Click here for Table 1 — Major PIC Components and Panel Locations

Pr ocessor Modu le (PSIO)

The PSIO is the brain of the PIC. This mo dule contains all of the operating softwar e need ed

to cont r ol the machine . T he 19XL uses 3 pr ess ur e transducers and 8 ther m is tors t o s ens e
pressures and temp er atures. These are connected to th e P S IO m odule. The PSIO als o
provides ou tputs to t he: gui de v ane act uator; oil pump; oil heater; hot gas bypass (optio nal);
motor cooling solenoid; and alarm contact. The PSIO communicates with the LID, the SMM,
and the optional 8-input modules for user interface and starter management.

Starter Management Module (SMM)

This module is loc ated withi n th e s tarte r ca binet. T his m odule initia tes PSIO co m m ands for
starter functions such as start/stop of the compressor, start/stop of the condenser and chilled
water pumps, start/stop of the tower fan, spare alarm contacts, and the shunt trip. The SMM
moni to r s star ter inputs s uc h as flow sw itches, line volt age, re m ote star t contac t, s par e safety,
condens er high press ur e, oil pum p int er lock, motor cur r ent si gnal, star ter 1M and run contac ts,
and kW t ransducer input (optional). The SMM co ntains logic ca pable of safely shutting d own t he
machine if communications with the PSIO are lost.

Local I nter f ace Devi ce (LID)

The LID is mounted to the control center and allows the operator to interface with the PSIO
or other CCN devices. It is the inpu t center for all local machine set point s , sc hedul es , set-u p
funct ions, and options. The LID has a STO P button, an alarm light, 4 button s for logic inputs ,
and a display. The function of the 4 buttons or ‘‘softkeys’’ are menu driven and are shown on the
display direc tly abo v e the key.

6-Pack Relay Board

This device is a c lus ter of 6 pilot relays located in the control c enter. It is energiz ed by th e
PSIO fo r the oil pu m p, oil heater, alar m , optional hot gas bypass re lay , and mo tor cooling
solenoid.

8-Input Modules

One optional module is factory installed in the control center panel when ordered. There can
be up to 2 of these module s per c hiller with 8 sp ar e inputs eac h. They ar e used whene v er
chilled water reset, demand reset, or reading a spare sensor is required. The sensors or 4 to 20
mA signals are field- installed.

The spare temperature sensors must have the same temperature/resistance curve as the
other tempe r ature sensors on this un it. These sensor s ar e 5,000 ohm at 75 F (25 C) .

Oil Heater Contactor (1C)

This contactor is located in the power panel and operates the heater at either 115 or 230 v. It
is cont r olled by the PIC to maintain oil te m per atur e dur ing mac hine sh utdown.

Oil Pump Contactor (2C)

This contact or is locat ed in the power panel. It oper ates all 200 to 575- v oil pumps . The PIC
energiz es the contac tor to turn on th e oil pump as necess ar y .

Hot Gas Bypa ss Contactor Relay (3C) (Optional )

This relay, located in the power panel, controls the opening of the hot gas bypass valve. The
PIC energizes the rel ay dur ing low load, high lift con ditions .

Control Transformers (T1-T4)

These t r ans formers con v er t incoming control v oltag e to either 21 vac power for the PSI O
module and opt ions modules, or 24 vac power f or 3 power panel contactor relay s , 3 contr ol
solenoid valv es, an d the gui de v ane act uator. They are locat ed in the power panel.

Clic k here for Figure 8 — 19XL C ontrols and Sensor Loc ati ons

Clic k here for Figure 9 — Cont r ol S ensors (Tempe rature)

Click here for Figure 10 — Control Sensors (Pressure Transducer, Typical)

Click here for Figure 11 — Control Panel (Front View), with Options Module

Click here for Figure 12 — Power Panel with Options

Control and Oil Heater Volt age Sel ecto r (S1)

It is poss ible to use either 115 v or 230 v inc oming cont ro l power in t he power panel . T he
switc h is s et to the vo ltage us ed at the job site .

LID Operation and Menus (

17, F igure 18

General

• The LID display will automatically revert to the default screen after 15 minutes if no
softkey activity takes plac e and if the machine is not in the Pu m pdown mode (Figur e

13).

• When not in the default screen, the upper right-hand corner of the LID always dis­plays the name of the screen that you have enter ed ( Figur e 14).

• The LI D m ay be c onfi gur ed in English or SI units, throug h the LID config ur ation
screen.

• Loca l Operat ion — By pressing the LOCAL sof tkey, t he P IC is now in the LOCAL
operation mode and the control will accept modification to programming from the LID
only . T he P IC will us e the Loc al Time Sc hedul e to determ ine mac hine st ar t and st op
times.

• CCN Operation — By pressing the CCN softkey, the PIC is now in the CCN operation

, and

Figure 19

Figure 13, Figure 14, Figure 15, Figure 16, Figure

)

mode, and the c ontrol will acc ept modi fications from any CCN interface or m odule
(with the pro per author ity), as well as the LID. The P IC wil l us e the CCN time sched­ule to determine start and stop times.

Alar m s and Alerts

Alarm ( *) and alert ( !) s tatus ar e indicated on the Status ta bles. An alarm ( *) will shut down
the compressor. An alert (!) notifies the operator that an unusual condition has occurred. The
machine will c ontinue to op er ate when an alert is s hown.

Clic k here for Figure 13 — LI D D efault Screen

Click here fo r Figure 14 — LID Service Scr een

Alarms are indicated when the control center alarm light (!) flashes. The primary alarm
message is viewed on the default screen and an additional, secondary, message and
troubleshooting infor m ation ar e s ent to th e A lar m History tab le.

When an alarm is detected, the LID default screen will free z e ( s top upd ating) at t he time of
alarm. The freeze enables the operator to view the machine conditions at the time of alarm. The
Status tables will show the updated information. Once all alarms have been cleared (by
pressing the RESET softkey), the default LID screen will return to normal operation.

Menu Structure

To perform any of the operations described below, the PIC must be powered up and h av e
successfully completed its self test.

• Press QUIT to leave the selected decision or field without saving any changes.
INCREASE DECREASE QUIT ENTER

• Pres s E NTER to leav e the se lec ted dec is ion or field and sav e c hanges.
INCREASE DECREASE QUIT ENTER

• Press NEXT to scroll the cursor bar down in order to highlight a point or to view more

points below the current screen.

NEXT PREVIOUS SELECT EXIT

• Press PREVIOUS to scroll the cursor bar up in order to highlight a point or to view

points above the cur r ent scr een.

NEXT PREVIOUS SELECT EXIT

• Press SELECT to view the next screen level (highlighted with the cursor bar), or to

override (if allowa ble) the highlighted point v alue.

NEXT PREVIOUS SELECT EXIT

• Press EXIT to return to the previous screen level.
NEXT PREVIOUS SELECT EXIT

• Press INCREASE or DECREASE to change the highlighted point value.
INCREASE DECREASE QUIT ENTER

To View Point Status (

Point Status is the actual value of all of the temperat ur es, pressures , relays , and ac tuators

sense d and controll ed by the PI C.

1.

On the Menu screen, press STATUS to view the list of Point Status tables.

Figure 15

STATUS SCHEDULE SETPOINT SERVICE

)

2. Press NE X T or PREV IOUS to highlight the desired status table. The lis t of tabl es is :

• Status01 — Status of control points and sensors

• Status02 — Status of relays and contacts

• Status03 — Status of both optional 8-input modules and sensors
NEXT PREVIOUS SELECT ENTER

3. Press SELECT to view the desired Point Status table desired.
NEXT PREVIOUS SELECT ENTER

4. On the Point Status table press NEXT or PREVIOUS until desired point is displayed on the

screen.

NEXT PREVIOUS SELECT ENTER

Override Operations

To Override a Value or Status

1.

On the P oint St atus table press NE X T or PRE V IO US to highlight the desi r ed point.

NEXT PREVIOUS SELECT EXIT

2.

Press S E LE CT to select the highlighted point. Then:

NEXT PREVIOUS SELECT EXIT

Click here for Figure 15 — Example of Point Status Screen (Status 01)

Click here for Figure 16 — 19XL Menu Structure

Click here for Figure 17 — 19XL Service Menu Structur e

For Discrete Points

For Analog Points

3. Press ENTER to register new value.

Note: When overriding or changing metric values, it is necessary to hold the softkey down for a

— Press START or STOP to select the desired state.

START STOP R ELEASE ENTER

— Press INCREASE or DECREASE to select the desired value.

INCREASE DECREASE RELEASE ENTER

NEXT PREVIOUS SEL ECT EXIT

few seconds in or der to se e a v alue change, es pecially on kilopa s c al v alues.

To Rem ov e an Override

1. On th e P oint Status table pres s NE X T or PREV IO US to highlight the desi r ed point.

NEXT PREVIOUS SELECT EXIT

2. Press S E LE CT to acc es s the hi ghligh ted point.
NEXT PREVIOUS SELECT EXIT

3. Press RELEASE to remove the override and return the point to the PIC’s automatic control.
INCREASE DECREASE RELEASE ENTER

Overr id e Indi cat ion

An override value is indicated by ‘‘SUPVSR,’’ ‘‘SERVC,’’ or ‘‘BEST’’ flashing next to the point

value on the St atus table.

Time Schedule Operation (

1.

On the Menu screen, press SCHEDULE.

STATUS SCHEDULE SETPOINT SERVICE

2.

Press NEXT or PREVIOUS to highlight the desired schedule.
PSIO Software Version 08 and lower:

OCCPC01S — LOCAL Time Schedule
OCCPC02S — CCN Time Schedule

PSI O Software Vers ion 09 and higher:

OCCPC01S — LOCAL Time Schedule
OCCPC02S — ICE B UILD Time Sch edule
OCCPC03-99S — CCN Time Schedule (Actual number is defined in Config table.)

NEXT PREVIOUS SELECT EXIT

Figure 18

)

3. Press SELECT to access and view the time schedule.

NEXT PREVIOUS SELECT EXIT

4. Press NE X T or PREV IOUS to highlight the desired period or overr ide th at you wish to

change.

NEXT PREVIOUS SELECT EXIT

5. Press S E LE CT to acc es s the hi ghligh ted peri od or ov err ide.
NEXT PREVIOUS SELECT EXIT

6.

a. Pre ss INCREASE or DECREASE to change the time values. Override values are in one-

hour inc r em ent s , up to 4 hours .

INCREASE DECREASE ENTER EXIT

b. Press ENABLE to select days in the day-of-week fields. Press DISABLE to eliminate

days f r om th e per iod.

ENABLE DISABLE ENTER EXIT

7. Press ENTER to register the values and to move horizontally (left to right) within a period.
ENABLE DISABLE EN TER EXIT

8. Press E X IT to lea v e the peri od or ov err ide.
NEXT PREVIOUS SELECT EXIT

9. Either return to Step 4 to select another period or override, or press EXIT again to leave the

current time schedule screen and save the changes.

NEXT PREVIOUS SELECT EXIT

Click here for Figure 18 — Example of Time Schedule Operation Screen

10. Holid ay Des igna tion (HO LIDEF table) ma y be found in the Service Operation section. You
must as s ign the m onth, day, and dur ation for the holiday. The Br oadcast func tion in the
Brod efs tab le also mus t be ena bled for holiday period s to f unc tio n.

To View and C hange Set Point s (

1.

To view the Set Point table, at the Menu screen press SETPOINT.

STATUS SCHEDULE SETPOINT SERVICE

2.

There are 4 set points on this screen: Base Demand Limit; LCW Set Point (leaving chilled
wate r se t point) ; ECW Set Po int (ent er ing chilled water set point); an d ICE BUILD se t point
(PSIO Software Version 09 and higher only). Only one of the chilled water set points can be
activ e at one time, and the ty pe of set point is act iv ate d in the Service menu. ICE B UILD is
als o ac tivated and configur ed in the S er v ice menu.

3.

Press NEXT or PREVIOUS to highlight the desired set point entry.

NEXT PREVIOUS SELECT EXIT

Figure 19

)

4. Press S E LE CT to modify t he highl ighted s et poin t.

NEXT PREVIOUS SELECT EXIT

5. Press INCREASE or DECREASE to change the selected set point value.
INCREASE DECREASE QUIT ENTER

6. Press ENTER to save the changes and return to the previous screen.
INCREASE DECREASE QUIT ENTER

Click here for Figure 19 — Example of Set Point Screen

Service Operation

To view t he m enu-dr iv en programs av ailab le for Serv ic e Ope r ation, see Service Operation

section. For examples of LID display screens, see Table 2 (begins on this page).

Table 2 — LID Screens

Note:

1.

Only 12 lines of information appear on the LID screen at any given time. Press NEXT or
PREVIOUS to highlight a point or to view points below or above the current screen.

2.

The LID may be configured in English or SI units, as required, through the LID configuration
screen.

3.

Data appearing in the Refer enc e Point Name s co lum n is used for CCN opera tions on ly .

4.

All options associated with ICE BUILD, Lead/Lag, CCN Occupancy Configuration, and Soft
Stopping are only available on PSIO Software Version 9 and higher.

Click on an example to view:

Example 1 — Status01 Display Screen
Example 2 — Status02 Display Screen
Example 3 — Status03 Display Screen
Ex ample 4 — Setpoint D i splay Scr een
Example 5 — Configuration (Config) Display Screen

Table 2 — LID Screens (Continued)
Click on an example to view:

Example 6 — Lead/Lag Configuration Display Screen
Example 7 — Service1 Display Screen
Example 8 — Service2 Display Screen
Example 9 — Service3 Display Screen
Example 10 — Maintenance (Maint01) Display Screen
Example 11 — Maintenance (Maint02) Display Screen
Example 12 — Maintenance (Maint03) Display Screen
Example 13 — Maintenance (Maint04) Display Screen

PIC System Funct ions

Note:

Throughout this manual, words printed in capital letters and italics are values that may be
view ed on the LID. See Table 2 for ex am ples of LID sc r eens. Point nam es ar e list ed in
the Description column. An overview of LID operation and menus is given in Figure 13,

Figur e 14, Figure 15, Figure 16, Figur e 17, Figure 18, and Fig ure 19 .

Capacity Control

The PIC co ntrols the machine capac ity by m odulating th e inlet guide vanes in res ponse t o
chil led water temperatur e c hanges away fro m the
may be change d by a CCN networ k devic e, or is det er m ined by the PIC ad ding any active
chilled water reset to the chilled water
(

Increase) BAND, PROPORTIONAL DEC (Decrease) BAND

(

Enter ing Chi lled Wa te r) GAIN

may be viewed/overridden on the Status table, Status01 selection.

to determine how fast or slow to respond.

SET POINT

CO NTRO L P OI N T

. The PIC uses the

, and the

. The

CONT ROL POINT

PROP OR TIO NAL INC

PROPORTIONAL ECW

CONT ROL POINT

Enteri ng Chilled Water Control

If this optio n is enable d, the PIC uses
modulate the vanes instead of

WATER

control opt ion may be v iewed /modif ied on the E quipment Configur atio n table, Config

LEAVING CHILLED WATER

EN TERING CHI LLED WATER

temperature.

temperat ur e to

ENTERING CHILLED

table .

Deadband

This is the tolerance on the chilled water/ brine temperature
temperatu r e goes out s ide of the
response until it is within tolerance. The PIC may be configured with a 0.5 to 2 F (0.3 to 1.1 C)
deadband.

For exam ple, a 1° F (0.6° C) deadband setting contro ls the water temperat ur e within ±0.5° F
(0.3° C) of the control poi nt. This m ay c aus e frequ ent gui de v ane movem ent if the chi lled wat er
load fl uc tuates frequ ently. A va lue of 1° F (0. 6° C) is the default sett ing.

DEADBAND

may be viewed or mo dified on the Equ ipm ent Se r v ic e1 table.

DEADBAND

, the P IC open s or cl os es the guide vanes in

CONT ROL POINT

. If the wate r

Proportional Bands and Gain

Propo r tiona l band is th e r ate at whic h the guide vane position is c or r ec ted in pr oporti on to
how far the chi lled water /brine temperature is f r om the contr ol point. Proporti onal gain
determ ines how quic k ly the gui de v anes reac t to how quickly the temperat ur e is m ov ing f r om
CONT ROL POINT .

The proport ional ba nd
one for t em perature response above the control po int, the other for response below the c ontro l
point.

The fir s t t y pe is c alled

can be v iewed/ m odified on the LID. There are t wo r es ponse modes,

PROP OR TI ON A L INC BA ND

, and it c an s low or quicken v ane
respo ns e to chilled water/ br ine tem per atur e above
setting of 2 to 10; the def ault set ting is 6.5.

PROPORTIONAL DEC BAND

DEADBAND

. It can be adjusted from a

can sl ow or quick en

vane response to chilled water temperature below deadband plus control point. It can be
adjus ted on the LID from a s etting of 2 to 10, and the defaul t setting is 6.0. I nc r easing either of
these settings will cause the van es to respond slower than a lower setting.

The

PROP OR TI ON A L EC W GAIN

3.0, with a default sett ing of 2.0 . I nc r ease this set ting to inc r ease guide va ne r es ponse to a
change in ent er ing chilled water te m per atur e. The proportional bands and gain ma y be v iewed/
modified on the Equipment Service3 table.

can be adjusted at the LID display from a setting of 1.0 to

Dema nd Limiting

The PIC will respond to the

guide vanes. It will compare the set point to either

COMPRESSOR MOTOR CURRENT

for the
setting is current limiting.

DEMAND LIMIT SOURCE

ACTIVE DEMAND LIMIT

(percentage), depending on how the control is configured

which is accessed on the SERVICE1 table. The default

set point by lim iting the ope ning of the

COMPRESSOR MOTOR LOAD

or

Machine Timers

The PIC maintains 2 runtime clocks, known as

ONTIME. COMPRESSOR ONTIME

can register up to 500,000 hours before the clock turns back to zero. The
a resettable timer that can be used to indicate the hours since the last service visit or any other
reason. The time can be changed through the LID to whatever value is desired. This timer can

indicates the total lifetime comp ressor run hours. Thi s timer

COMPRESSOR ONTIME

and

SERVICE

SERVICE ONTIME

is

register up to 32,767 hours before it rolls over to zero.

The chiller also maint ains a s tart-to- s tart timer and a stop- to-sta r t t im er . Thes e timers limit
how soon the machine ca n be s tart ed. See the Start-Up/Shutdown/Recycle Sequence section
for operational information.

Occupancy Schedule

This sc hedule determ ines when the c hiller is eithe r occ upied or unoccupied.

Each sc hedul e c ons ists of from one to 8 occupied/unoccupie d time periods, se t by the
operator. These time per iods can be enabled to be in ef fect, or not in effect, on each day of the
week and for holidays. The day begins with 0000 hours and ends with 2400 hours. The machine
is in OCCUPIED mode un les s an unocc upie d time period is in effect .

The machine will shut down when the sc hedule goes to UNO CCUPI E D. These s c hedules
can be se t up to follow the building sch edule or t o be 100% OCCUPIED if the operat or wishes.
The schedules also can be bypassed by forcing the Start/S top command on the PIC Status
screen to star t. The schedules also can be overridden to k eep the unit in an OCCUPIE D m ode
for up to 4 hour s , on a on e- time ba s is .

Fig u re 18 shows a schedule for a typical office building time schedule, with a 3-hour, off-peak

cool down period from midnight to 3 a.m., following a weekend shutdown. Example: Holiday
peri ods ar e unoccupie d 24 hours per day. T he build ing operates Mo nday through Friday, 7:00
a.m. to 6:00 p.m., with a Saturday schedule of 6:00 a.m. to 1:00 p.m., and includes the Monday

midnight to 3:00 a.m. weekend coo l- down schedule.
Note: This schedule is for illustration only, and is not intended to be a recommended schedule

for chiller operation.

PSIO Software Version 08 and Lower

Whene v er the chiller is in t he LOCAL mode, the machine wi ll s tart when the Occ upancy
Schedule 01 indicates OCCUPIED. When in the CCN mode, Occupancy Schedule 02 is used.

PSIO S oft ware V ersion 09 and Hig her

The Local Time Schedule is still the Occupancy Schedule 01. The Ice Build Time Schedule is
Schedule 02 and the CCN Default Time Schedule is Schedule 03. The CCN schedule number
is defined on the Config table in the Eq uipment Configur ati on table. The sch edule number can
change to any value fr om 03 to 99. If this schedule num ber is ch anged on the Config table, the
operator mus t use the A tt ac h to Network Dev ice ta ble to up load the new number int o th e
Schedule screen. See Figure 17.

Safety Controls

The PIC mo nitors all safe ty c ontro l input s , and if required, s huts down the mac hine or limit s
the gui de v anes to protec t the mac hine from possible da m age from any of the following
condition s :

• high bearing temp er ature

• high m otor winding temperatur e

• high dis c harge temp er ature

• low oil pressure

• low cooler refrigerant temperature/pressure

• condenser high pressure or low pressure

• inadequate water/brine cooler and condenser flow

• high, low, or los s of voltage

• excessive motor acceleration time

• excessive starter transition time

• lack of motor current signal

• excessive motor amps

• excessive compressor surge

• temper atu r e and tran s duc er fau lts

Starter faults or optional protective devices within the starter can shut down the machine.
These devices are dependent on what has been purchased as options.

CAUTI ON

If comp ressor motor overload occ urs, che ck t he mot or for grounded o r op en
phases befo re at t empt in g a restart.

If the controller in itiates a s afety s hutdown, it dis plays the fault on the LID display with a
prima r y and a s ec ondary mes s age, and energiz es an alarm relay in the star ter an d blinks the
alarm light on the contr ol c enter . T he alarm is s tored in me m or y and can be viewed in the PIC
alarm table al ong with a m es s age for troubleshoo ting.

To give a better warning as to the operating condition of the machine, the operator also can
defin e alert limits on v ar ious m onitor ed inputs . Safe ty c ontac t and aler t limit s are defin ed in

Table 3. Alarm and alert messages are lis ted in th e Troubleshooting Guide section.

Click here for Table 3 — Protective Safety Limits and Control Settings
(and figure following table)

!

CAUTION

Shunt Trip

The shunt trip function of the PIC is a safety trip. The shunt trip is wired from an output on the
SMM to the motor circuit breaker. If the PIC tries to shut down the compressor through normal
shutdown procedu r e but is unsucces s ful for 30 s ec onds, the shunt trip outp ut is energized and
cause s the circ uit brea k er to trip off . If ground fault protec tio n has been ap plied t o th e s tarte r ,
the ground fault trip will also ene r giz e the sh unt tri p to trip the circuit breaker.

Def a u lt Scr een Fr eeze

Whenever an alarm occurs, the LID default screen will freeze displaying the condition of the
machine at th e time of alar m . Knowledge of the operat ing state of the chiller at the ti m e an
alarm occurs is useful when troubleshooting. Current machine information can be viewed on the
Status tables. Once all existing alarms are cleared (by pressing the RESET softkey), the defaul t
LID will retur n normal operation.

Motor Cooling Control

Motor te m per atu r e is re duc ed by refrige r ant enter ing the m otor shell an d ev aporat ing. The
refrigerant is regulated by the motor cooling relay. This relay will energize when the compressor
is runn ing and motor tem perature is above 12 5 F (51.7 C) . T he r elay will close when mo tor
temperature is below 100 F (37.8 C). Note that there is always a minimum flow of refrigerant
when th e c om pr ess or is operat ing for mot or c ooling; the re lay only controls addi tiona l
refrigerant to the motor.

Ramp Loading Control

The ramp loading control slows down the rate at which the compressor loads up. This control
can pre v ent the c om pr essor from loading up dur ing the s hort pe r iod of tim e when the m ac hine
is star ted, and the chi lled wat er loop ha s to be broug ht down to normal design condi tions. This
helps reduce electrical demand charges by slowly bringing the chilled water to control point.
Howev er , the to tal power dr aw during this per iod remains almost uncha nged.

There are 2 methods of r am p loadi ng with the PIC. Ram p loading can be bas ed on chi lled
water tempe r ature or on moto r load.

1.

Temperat ur e r am p load ing
chilled water temperature decreases by an operator-configured rate. The lowest
temperat ur e r am p table will be used the first time the ma c hine is started (a t
commissioning ) . T he lowest temper ature ra m p r ate wil l als o be used if mach ine powe r has
been of f for 3 ho ur s or m or e ( ev en if the motor ra m p load is s electe d) .

2.

Motor load ramp load ing
compressor motor load increases by an operator-configured rate.

limits th e r ate at whic h either leaving chilled water or ent er ing

limits the rate at which the compressor motor current or

The

TEMP (Temperature) PULL DOWN, LOA D P ULL DO WN

may be viewed /modified on t he LID Equ ipm ent Config ur ation table, Config table ( s ee Table 2).
Motor load is th e default type .

, and

SELECT RAMP TYPE

Capacity Ov erride (Table 4)

These can prevent some safety shutdowns caused by exceeding motor amperage limit,
refrigerant low temperature safety limit, motor high temperature safety limit, and condenser high
pressure limit. In all cases there are 2 stages of compressor vane control.

1.

The vanes are held from opening further, and the status line on the LID indicates the reason
for th e ov er r ide.

2.

The vanes are c losed until c ondition decreases below the first step set point, and then the
vanes are released to normal capacity control.

Whene v er the mot or c ur r ent dema nd limit set point is reached, it activ ates a capacit y
override, again with a 2-step process. Exceeding 110% of the rated load amps for more than 30
secon ds will initiat e a s afety sh utdown.

The compressor high lift (surge prevention) set point will cause a capacity override as well.
When t he s ur ge prevention set po int is reac hed, the cont r oller normally will only ho ld the guide
vanes from opening. If s o equipped, th e hot gas bypass v alv e will open inst ead of ho lding the
vanes .

Click here for Table 4 — Capacity Overrides

High Discharge Temperature Cont r ol

If the discharge temperature increases above 160 F (71.1 C) (PSIO Software Version 09 and
higher) or 180 F (82 C) (PSIO Software Version 08 or lower), the guide vanes ar e proportionally
opened to increase gas flow through the compressor. If the leaving chilled water temperature is
then brough t 5° F (2.8° C) below the c ontro l s et poin t t em perat ur e, the controls will br ing the
machine into the recycle mode.

Oil Sump Temperature Control

The oil sump temperature control is regulated by the PIC which uses the oil heater relay
when th e m ac hine is s hut down.

As part of the pre-start checks executed by the controls, oil sump temperature is compared
against evaporator r efrigeran t t em perat ur e. If th e difference bet ween t hes e 2 temp er ature s is
50 F (27. 8 C) or les s , the s tart-u p will be de lay ed unt il the oil tempe r ature is 50 F (27.8 C) or
more. On c e this te m per atur e is c onfirmed, the start- up cont inues.

PSIO Softwa r e Vers ion 08 and Lower

The oil heater relay is energiz ed when ev er the chi ller co m pr es s or is off , and the oil sump
temperatu r e is les s than 140 F (60 C) or s um p temperatur e is less tha n the cooler ref r igerant
temperatu r e plus 60° F (33.3° C) . The heat er is then turned off when the oil sump temp er ature
is: 1) more than 160 F (71.1 C); or 2) the sump temperature is more than 145 F (62.8 C) and
more than the cooler refrigerant temperature plus 65° F (36.1° C). The heater is always off
duri ng s tart- up or when the c om pres s or is r unnin g.

PSIO Software Version 09 and Highe r

The oil heater relay is energiz ed when ev er the chi ller co m pr es s or is off and the oil s um p
temperatu r e is les s than 150 F (65.6 C) or the oil su m p temperature is les s than the coole r
refr igerant temperatur e plus 70° F (39° C). The oil heater is tu rn ed off when the oil sump
temperatu r e is either 1) mo r e than 160 F (71.1 C) ; or 2) the oil s um p tempe r ature is m or e than
155 F (68. 3 C) and mor e than the coole r re frigerant temperat ur e plus 75° F (41.6° C) . Th e oil
heate r is always off dur ing st ar t-up or when the c om press or is r unnin g.

When a po wer fail ur e to the PS IO m odule has occur r ed for more than 3 hour s ( i.e., initial
start-up), the oil sump is heated to 100° F (56° C) above the evaporator refrigerant temperature
or 190 F (88 C) , whi c hev er is lower. O nc e this tem perat ur e is r eached, the oil pump will be
energiz ed fo r 1 to 2 minutes or until the oil sump temperature c ools to below 145 F (63 C). The
norma l heati ng algorithm is now followed once ramp loadin g has been complet ed.

After a 3- hour power failure, the oil temper ature mus t rise t o the hig her oil tem per atur e. The
contr ols will delay the start of the com pr es s or unt il this t em perat ur e is m et.

Oil Cooler

The oil mu s t be cooled when the compresso r is ru nning. This is acc om plished thr ough a
small, plat e- type he at exchanger located behind the oil pump. The hea t exc hang er us es liqui d
condenser refrigerant as the cooling liquid. A refrigerant thermal expansion valve (TXV)
regulates refrigerant flow to control oil temperature entering the bearings. There is always a flow

regulates refrigerant flow to control oil temperature entering the bearings. There is always a flow
of refrigerant bypassing the thermal expansion valve (TXV). The bulb for the expansion valve is
strapped to the oil supply line leaving the heat exchanger and the valve is set to maintain 110 F
(43 C).

Note: The expansion valve is not adjustable. Oil sump temperature may be at a lower tempera-

ture.

Remote Start/ St op Contr ol s

A remote device, such as a time clock which uses a set of contacts, may be used to start and
stop th e m ac hine. However, the dev ice should no t be programmed to star t and sto p the
machine in excess of 2 or 3 times every 12 hours. If more than 8 starts in 12 hours occur, then
an Excessive Starts alarm is displayed, preventing the machine from starting. The operator
must reset the alarm at the LID in order to override the starts counter and start the machine. If
Autom atic Re s tart After a Power Fail ur e is not activ ate d when a pow er failur e oc c ur s , and the
remot e c ontac t is c losed, the machine wi ll indicate an alarm bec ause of the loss of voltage.

The cont ac ts fo r Rem ote Star t are wired into the star ter at ter m inal st r ip TB5, term inals 8A
and 8B. See the ce r tified drawin gs for furt her det ails on contact r atings . T he c ontac ts m us t be
dry (no power).

Spare Safety Inputs

Norma lly c los ed (NC) digital inputs for additional f ield-supplied safeties ma y be wir ed to the

spare pr otect iv e limit s input channel in place of the fac tory-ins talled jumper. (W ir e m ulti ple
input s in s er ies.) The opening of any c ontac t will result in a s afety sh utdown and LID dis play.
Refer to the cer tified drawings for s afety co ntact ra tings.

Anal og tempe r ature sensors ma y als o be add ed to the opt ions m odules, if installed. These
may be programmed to cause an alert on the CCN network, but will not shut the machine down.

Spare Alarm C ont acts

Two spar e sets of alarm con tacts are provided wi thin the s tarter . The contact ra tings are
provided in the cert ified dr awings. The contac ts are locat ed on terminal str ip TB6, terminals 5A
and 5B, and terminals 5C and 5D.

Condenser Pump Control

The machine will moni tor the

CONDENSER PRESSURE

and may turn on t his pump if the

pressure becomes too high whenever the compressor is shut down.

PRESSURE OVERRIDE

Equipment Service1 LID table and has a default value (Table 4). If the

PRESSURE

is greater than or equal to the

ENTERING CONDENSER WATER TEMP (Temperature

condens er pum p will en er gize to try to decrease th e pr es s ure. The pump will turn off when the
condenser pressure is less than the pressure override less 5 psi (34 kPa), or the

REFRIG (Refrigerant) TEMP

temperature.

is used to determine this pr ess ur e point. This va lue is found on the

CONDENSER PRESSURE OVERRIDE

) is less than 115 F (46 C), then the

is within 3° F (2° C) of the

ENTERING CONDENSER WATER

CONDENSER

CONDENSER

, and the

CONDENSER

Condenser Freeze Pr evention

This control algorithm helps prevent condenser tube freeze-up by energizing the condenser
pump relay. If the pump is controlled by the PIC, starting the pump will help prevent the water in
the condenser from freezing. Condenser freeze prevention can occur whenever the machine is
not running ex c ept when it is either ac tively in pu m pdown or in Pumpdown Lo c k out with the
freeze prevention disabled (refer to Control Test table, Pumpdown/Terminate Lockout tables).

When the CONDENSER REFRIG TEMP is less than or equal to the CONDENSER FREEZE
POINT , or the EN TERING CO NDENS E R WATER temperat ur e is les s than or eq ual to the
CONDENSER FREEZE POINT, then the CONDENSER WATER PUMP shall be energized
until the CONDENSER REFRIG TEMP is greater than the CONDENSER FREEZE POINT plus
5° F (2.7° C). An alarm will be generated if the machine is in PUMPDOWN mode and the pump
is ener giz ed. An aler t will be generated if the mac hine is not in P UM P DOWN m ode and the
pump is ener gized. If in re c y c le s hutdown, the m ode shall trans itio n to a non-recycle s hutd own.

Tower-Fan R el ay

Low condenser water temperature can cause the chiller to shut down on low refrigerant
temperature. The tower fan relay, located in the starter, is controlled by the PIC to energize and
deenergize as the pressure differential between cooler and condenser vessels changes in order
to prevent low condenser water temperature and to maximize machine efficiency. The tower-fan

relay ca n only ac c om plish t his if the r elay has been add ed to the cooling tower temperatur e
contr oller. The
is runn ing, flow is ver ified , an d the differen c e betwe en c ooler and cond ens er pres s ur e is mo r e
than 45 ps id ( 310 kP ad) ( 30 psid [ 207 kPad] for HFC- 134a ) or enterin g c ondenser wat er
temperatu r e is gr eater than 85 F (29 C) . The
condens er pum p is off, flow is los t, the evapora tor refrigerant temperat ur e is less than the
override tem perat ur e, or th e differential pr ess ur e is less than 40 psid (279 kPad) (28 psid [1 93
kPad] fo r HFC-134a) and enterin g c ondensing wa ter is les s th an 80 F (27 C).

IMPORTANT: A f ield-su ppli ed water t emper at ure con t rol system for co ndens er water
should be installed. The system should maintain the leaving condenser water tempera­ture at a t emperat ure that is 20° F (11° C) above the leaving chi lled wat er temperat ure.

The tower-fan relay control is not a substitute for a condenser water temperature
control. Wh en used with a Wat er Temperatur e Control system, t he tower f an
relay control can be used to help prevent low condenser water temperatures.

TOWER FAN RELAY

CAUTI ON

!

is turned on wheneve r the

TOWER FAN RELAY

CAUTION

CONDENSER WATER PUMP

is deenergized when the

Auto. Restart After Power Failur e

This opt ion may be enabl ed or disabled, and may be v iewed/ m odified in the Config table of
Equipment Configuration. If enabled, the chiller will start up automatically after a single cycle
dropout, low, high, or loss of voltage has occurred, and the power is within ±10% of normal. The
15- and 3- m inut e inhibi t t im er s ar e igno r ed during this type of star t-up.

When power is restored after the power failure, and if the compressor had been running, the
oil pump will be energ iz ed for on e m inute pr ior to the evaporat or pump energizing. A uto restart
will th en c onti nue like a normal s tart- up.

If pow er to the PSIO mo dule has been off for more than 3 hours, t he P IC will ra is e the oil
temperatu r e 100° F (56° C) above the ev aporat or temperatur e. Refrigerant normally migr ates
into t he oil whe n the oil heater is left of f f or ex tended periods of tim e. The PIC operates the oil
pump for 1 to 2 minutes to ensure that the oil is free of excess refrigerant. Once this algorithm is
completed, the REST A RT of the chille r will cont inue.

Water/Br ine Reset

Three types of chilled water or brine reset are available and can be viewed or modified on the
Equipment Configuration table Config selection.

The LID default screen status message indicates when the chilled water reset is active. The
Control Point temperat ur e on the Status0 1 table indicates the m ac hine’s curr ent reset
temperatu r e.

To acti v ate a reset type, inpu t all configurat ion inf or m ation for that reset t y pe in the Config
table. Then input the reset type number in the SELECT/ENABLE RESET TYPE input line.

1. Reset Ty p e 1
rese t based on a 4 to 20 mA in put sign al. This type permits up to ±30° F (±16° C) of
automatic reset to the chilled water or brine temperature set point, based on the input from
a 4 to 20 mA s ignal. This signal is hardwi r ed into the numbe r one 8- input module.

If the 4- 20 mA si gnal is externally po wer ed fro m the 8-inp ut module, the si gnal is wir ed to
terminals J1-5(+) and J1- 6(–). If the signal is to be internally powered by the 8-input module
(for ex am ple, when using variable re s is tance ) , t he s ignal is wired t o J 1- 7( + ) and J1-6( –).
The PIC must now be configured on the Service2 table to ensure that the appropriate power
sour c e is ident ified.

2. Reset Ty p e 2
reset based on a remote temperature sensor input. This type permits ±30° F (±16° C) of
auto m atic res et to the se t point based on a t em perat ur e s ensor wir ed to the numbe r one 8­input m odule (s ee wiring diagr am s or c er tified drawings).

The t em perat ur e s ensor m us t be wired to terminal J1 - 19 and J1- 20.
To configur e Reset Type 2, enter the temperat ur e of the rem ote se ns or at the point where
no temperature reset will occur. Next, enter the temperature at which the full amount of

(Requir es opti onal 8-input m odule) — A utomatic c hilled water temperatur e

(Requir es opti onal 8-input m odule) — A utomatic c hilled water temperatur e

reset will occur. The n, enter the maxi mum amount of re set required t o oper ate the machine.

Reset Type 2 ca n now be act iv ated.

3. Reset Ty p e 3
diff er ence. This typ e of reset will add ±30 ° F (±16° C) bas ed on the temperatur e difference
betw een ent er ing and leav ing chille d water tem perature. This is th e only type of reset
available without the ne ed of the num ber one 8-inp ut module. No wiring is r equired for this
type as it alre ady us es the co oler wat er s ens ors .

To configur e Reset Type 3, enter the ch illed wa ter temp er ature diffe r enc e (the differ enc e
betw een ent er ing and leav ing chille d water) at which no tempe r ature reset occurs. T his
chi lled water tempe r ature difference is usually the full design load tempe r ature difference.
The difference in ch illed water temperat ur e at whic h the full amount of res et will oc c ur is
now ent er ed on t he next in put line. Next , t he am ount of reset is enter ed. Res et Type 3 can
now be activated.

— Automatic chilled water temperature reset based on cooler temperature

Demand Limit Control, Option — (Requires Optiona l 8-Input Module)

The demand limit may be externally controlled with a 4 to 20 mA signal from an energy
management system (EMS). The option is set up on the Config table. When enabled, the
contr ol is set f or 100% demand wi th 4 mA and an operator c onfi gur ed minimum demand set
point at 20 mA.

The Demand Reset input from an energy management system is hardwired into the number
one, 8-input module. The signal may be internally powered by the module or externally
powered. If the signal is externally powered, the signal is wired to terminals J1-1(+) and J1-2(–).
If the signal is inter nally powered, the signal is wir ed to term inals J1- 3(+ ) and J 1- 2(–). When
enabled, the contr ol is s et for 100% demand with 4 m A and an ope r ator configur ed minimum
demand s et poi nt at 20 mA.

Surge Prevention Algor ithm

This is an operator configurable feature which can determine if lift conditions are too high for
the compr ess or and then take corr ec tive action. Lift is defined as th e differ ence bet ween the
pressure at the impel ler ey e and t he im pell er dis c harge. The max imum lift tha t a parti c ular
impeller wheel can perfor m va r ies with the gas flow ac r oss the impeller, and the si z e of the
wheel.

The alg or ithm f ir s t determ ines if cor r ecti v e ac tion is nec es s ary . T his is done by checking 2
sets of operator configured data points, which are the MINIMUM and the MAXIMUM Load

Points, (T1/P1;T2/P2). These points have default settings for each type of refrigerant, HCFC-22
or HFC-134a, as defined on the Service1 table, or on Table 4. These settings and the algorithm
function are graphically displayed in Figu re 2 0. The two sets of load points on this graph (default
settings are shown) describe a line which the algorithm uses to determine the maximum lift of
the compressor. Whenever the actual differential pressure between the cooler and condenser,
and the temperature differenc e bet ween the enteri ng and leaving ch illed wa ter are above th e
line on the graph (as defined by the MINIMUM and MAXIMUM Load Points) the algorithm will
go into a co r r ec tive action m ode. If the ac tua l v alues are below the line , t he algorithm takes no
action. Modification of the default set points of the MINIMUM and MAXIMUM load points is
described in Figu r e 21.

Corre c tive action can be taken by making one of 2 c hoices . If a hot gas by pass line is
present, and the hot gas is configured on the Service1 table, then the hot gas bypass valve can
be energized. If a hot gas bypass if not present, then the action taken is to hold the guide vanes.
See Tabl e 4, Capac ity Overr ides. B oth of the s e c or r ec tive actions will reduce t he lift
exper ienced by the compress or and hel p to prevent a surge cond ition. Sur ge is a c ondition
when the lift becomes so high that the gas flow across the impeller reverses. This condition can
eventuall y ca us e m ac hine dam age. The surge pr event ion alg or ithm is intended to notify the
operator th at machine oper ating co nditions ar e marginal, and to take ac tio n to help prev ent
machine dam age such as lowering enter ing conden s er water tem perat ur e.

Surge Protection

Surging of th e c om pr essor c an be det er m ined by t he P IC through operator co nfigur ed
settings. S ur ge will ca us e am perage fluc tuations of the compres s or motor. The P IC moni tors
these amperage swings, and if the swing is greater than the configurable setting in one second,
then one surge count has occurred. The SURGE DELTA PERCENT AMPS setting is displayed
and configured on the Service1 screen. It has a default setting of 25% amps, SURGE
PROTECTIO N COUNTS c an be monitore d on the Mai nt03 table.

A surge prote c tion shu tdown of t he m ac hine will occur when ev er the surge prot ec tion
counter reaches 12 counts within an operator specified time, known as the SURGE TIME
PERIOD. The SURGE TIME PERIOD is displayed and configured on the Service1 screen. It
has a default of 5 minutes .

Click here fo r Figure 20 — 19XL Hot Gas Bypass/Surge Prevention

Click here for Figure 21 — 19XL with Default Metric Settings

Lead/Lag Control

Note:

chiller in a 2-chiller water system. Refer to Figure 16 and Figure 17 for menu, table, and screen
selec tion in format ion. On m ac hines t hat have PSI O software wit h Lead/Lag capabil ity, it is
possible to ut ilize t he P IC cont r ols to pe r form the lead/l ag function on 2 mac hine s . A third
machine can be added to the lead/lag system as a standby chiller to start up in case the lead or
lag chiller in the system has shut down during an alarm condition and additional cooling is
required.

Note:

Lead/ lag control is only availab le on machines with PSI O Software Ver s ion 09 or higher.

Lead/lag is a control system process that automatically starts and stops a lag or second

Lead/lag configuration is viewed and edited under Lead/Lag in the Equipment Configura­tion t able (located in the Serv ice menu). Le ad/la g s tatus dur ing machine operation is
viewed in the MAINT04 table in the Control Algorithm Status table. See Table 2.

Lead/Lag System Requirements:

• all mac hines m us t have PSIO software ca pable of per forming the lead/lag fu nc tion

• water pumps M US T be ener giz ed fro m the PIC controls

• water flows sh ould be consta nt

• CCN Time Schedules f or all mac hines mus t be identical

Operat ion Fe atures:

• 2 chiller le ad/lag

• addition of a t hir d chiller for bac k up

• manu al r otation of lead chiller

• load balancing if c onfig ur ed

• staggered restart of the chillers after a power failure

• chillers may be pipe d in parallel or in series c hilled water flow

Common Point Sensor Installation

Lead/ lag operation does not r equire a c om m on chilled water poin t sensor. Common poin t
sensors can be added to the 8-input option module, if desired. Refer to the certified drawings for
termination of sensor leads.

Note:

senso r is not used, the leav ing chilled wa ter sensor of the upstream chiller must be moved into
the lea v ing chilled wa ter pipe of t he downstrea m ch iller.

If the common point sensor option is chosen on a chilled water system, both machines
should have their ow n 8- input option m odule an d c om m on poin t sensor ins talled. Each
machine will us e its ow n c om m on point sens or for cont r ol, whe n th at machine is desig­nated as the lead chiller. The PIC cannot read the value of common point sensors
installed on other machines in the chilled water system.

When installing chillers in s er ies, a comm on point se ns or s hould be used. If a common poin t

If ret ur n c hille d water control is re quired on chill er s piped in series, the com m on point return

chil led water s ens or should be installed. If this sens or is not ins talled, the return chilled water
senso r of t he downstrea m ch iller mus t be relocated to the r eturn chilled water pipe of th e
upstream machine.

To properly c ontrol the common s upply point temperature se ns or when chille r s ar e piped in
parallel, the water flow thr ough the s hutdown chillers m us t be isol ated so t hat no water bypass
around the operating chiller occurs. The common point sensor option must not be used if water
bypas s ar ound th e operat ing chiller is oc c ur r ing.

Machi ne Communication Wiri ng

Refer to the machine’s Installation Instructions, Carrier Comfort Network Interface section for
inform ation on machine com m unicat ion wiring.

Lead/Lag Operation

The PIC co ntrol provides the ability t o operat e 2 c hillers in the LE A D/LAG mo de. It also
provides the additional ability to star t a designated standby c hiller when either the lead or lag
chil ler is faulted and ca pac ity requirements ar e not met . The lead/lag option operat es in CCN
mode only . If any other ch iller c onfigur ed for le ad/la g is s et to the LOCA L or OFF modes, it will
be unavailable for lead/ lag operation.

Note:

Lead/lag configuration is viewed and edited in Lead/Lag, under the Equipment Configu­ration table of the Service menu. Lead/lag status during machine operation is viewed in
the MAINT04 table in the Control Algorit hm S tatus table.

Lead/Lag Chiller Configuration and Operation

The conf igured lead chiller is identified when the LEAD/LAG SE LE CT valu e for tha t chiller is
configured to the value of ‘‘1.’’ The configured lag chiller is identified when the LEAD/LAG
SELECT for that chiller is co nfigur ed to the value of ‘‘2.’’ The standby c hiller is configur ed to a
value of ‘‘3.’’ A value of ‘‘0 ’’ disables the lead/ lag in that chill er .

To configure the LAG ADDRESS value on the LEAD/LAG Configuration table, always use
the address of the other chiller on the system for this value. Using this address will make it
easier to rotate the lead and lag machines.

If the address assignments placed into the LAG ADDRESS and STANDBY ADDRESS
values conflict, the lead/lag will be disabled and an alert (!) message will occur. For example, if
the LAG ADDRESS matches the lead machine’s address, the lead/lag will be disabled and an
alert (!) message will occur. The lead/lag maintenance screen (MAINT04) will display the
message ‘INV A LID CONF IG’ in the LEAD/ LA G CONFIGUR A TI ON and CURRE NT MO DE
field s .

The lea d c hiller r es pond s to normal start/s top con trols s uc h as oc c upan c y schedule, forc ed
start/ s top, and remote sta r t contac t inputs. After c om pleting start up and ram p loadi ng, the PIC
evaluates the need for additional capacity. If additional capacity is needed, the PIC initiates the
start up of the chiller configured at the LAG ADDRESS. If the lag chiller is faulted (in alarm) or is
in the OFF or LOCAL modes, then the chiller at the STANDBY ADDRESS (if configured) is

requested to start. After the second chiller is started and is running, the lead chiller shall monitor
conditions and evaluate whether the capacity has reduced enough for the lead chiller to sustain
the system alone. I f the capacity is re duced enough for the lead chiller to sustai n the CONTROL
POINT te m per atu r es alone, then the operat ing lag ch iller is s toppe d.

If the lead chiller is stopp ed in CCN mode for any re as on other than an alar m ( *) c ondition,
then the lag and standby c hille r s ar e s toppe d. If the co nfigur ed lead chille r stops for and ala r m
condition, then the configured lag chiller takes the lead chiller’s place as the lead chiller and the
standby chiller ser v es as the la g c hiller.

If the config ur ed lead ch iller does not co m plete the start- up bef or e the PRESTART FAULT
TIMER (user configured value) elapses, then the lag chiller shall be started and the lead chiller
will s hut down. The lead chiller then m onitor s the sta r t request from the ac ting le ad c hille r to
start. The PRESTART FAULT TIMER is initiated at the time of a start request. The PRESTART
FAULT TIMER’s function is to provide a timeout in the event that the r e is a pr es tart alert
condition pr ev enting the machine from s tarting in a ti m ely m anner. The timer is c onfig ur ed
under Lead/ Lag, found in the E quipment Conf iguration table of t he S er v ice m enu.

If the lag chiller doe s not achie v e s tart-up before the PR E S TART FAU LT TIMER elapses ,
then the lag chiller shall be stopped and the s tand by c hiller will be re quested to start, if
configured and ready.