Carrier 17-19EX User Manual

17/19EX
50/60 Hz
Centrifugal Liquid Chillers
®
with 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. 531-715 9-95 Form 17/19EX-1SS Replaces: 19EX-1SS

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.
Carrier Corpor ation 1995
©
DANGER
DO NOT VENT refrigerant relief valves within a building. Outlet from rupture disc or r elief v alve must be ve nte d outdoor s in accordanc e wit h the lat e st e dition of ASHRAE 15 (Safety Code for Mechanical Refrigeration). The accumulation of ref rigerant in an enclos ed space can displ ace oxygen and cause asphyxi at ion.
PR OVIDE adequate ventilation in accordan ce with ASHRAE 15, especial ly for enclosed and low overhead spaces. Inhalation of high concentrations of vapor is harmful an d may cause heart irregu larities, unconsci ou snes s, or death . Misuse can be fat al. V apor is heavier t han air and reduc es t he amount of oxygen avail­able for breathing. Product causes eye and skin irritation. Decomposition prod­ucts are hazardous.
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 checking the instruction literature and the design pressures on the 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 NO T W E LD OR FLAM E CUT any refrigerant li ne or vessel until al l refri gerant (
liquid and vapor
placed with dry air or nitrogen and the work area should be well ventilated.
erant in contact with an open flame produces toxic gases
DO NOT USE eyebolts or eyebolt holes to rig machine sections or the entire assembly.
DO NOT work on high-voltage equipment unless you are a qualified electrician. DO NOT WORK ON electrical components, including control panels, switches,
start ers, or o il heater un t il you are su re ALL POW E R IS OFF and n o residual volt­age ca n l eak from capaci t ors or so li d-state compo nents.
LOCK OPEN AND TAG electrical circuits during servicing. IF WORK IS INTER­RUP TED, con f irm that all circui t s are deenergized befo re resuming work.
AVOID S PILLI NG li quid ref r ige r an t on s ki n o r ge t ting i t into the e yes . U S E S A FETY GOGGLES. Wash any spi lls from the skin wi t h soap and water. If any en t ers the eyes, IMMEDIATELY FLUSH EYES with water and consult a physician.
NEVER APPLY an open flame or live steam to a refrigerant cylinder. Dangerous overpressure can result. When necessary to heat ref rigerant , u se only warm (110 F [43 C]) water.
DO NOT REUSE disposable (nonreturnable) cylinders or attempt to refill them. It is DANGEROUS AND ILLEGAL. When cylinder is emptied, evacuate remaining
) has been removed from chiller. Traces of vapor should be dis-
!
WARNING
Refrig-
.
WARNING
gas pr essure, loosen the collar and un screw and dis card the valve stem . DO NOT INCI NE RATE .
CHECK THE REFRIGERANT TYPE before adding refrigerant to the machine. The introduction of the wrong refrigerant can cause damage or malfunction to this machine.
Oper a tion of t hi s eq uipment with r e fri ge ra nts othe r tha n those c ite d he r ei n s ho uld comp ly with AS HRAE-15 ( lates t edi t ion). Con t act Carrier for further informati on on use of this machine with other refrigerants.
DO NOTATTEMPT 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 brea king an y ref rigerant con nection.
CAREFULLY INSPECT all relief devices, rupture discs, and other relief devices A T LEAST ONCE A YEAR. If machine operates in a corrosive atmosphere, inspect the devi ces at mo re 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 valve body or mechanism. Replace the device.
DO NO T i ns t all reli ef devices in ser ies or bac kwards. USE CARE when working near or in line with a compressed spring. Sudden
release of the spring can cause it and objects in its path to act as projectiles.
!
WARNING
CAUTION
DO NOT STEP on refrigerant lines. Broken lines can whip about and cause per­sonal i nj ury.
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 cov­ers or other heavy components. Even if components are light, use such equip­ment when there is a risk of slipping or losing your balance.
BE AWARE t hat cer t ain auto mat ic star t arrangements CAN ENGA GE THE STARTER. Open the disconnect the machine or pump.
USE only repai r or repl acement parts th at meet the co de requirement s of the original equipment.
DO NOT VENT OR DRAIN waterboxes containing industrial brines, liquid, gases, or semisolids without permission of your process control group.
DO NOT LOOSEN waterbox cover bolts until the waterbox has been completely drained.
DOU B LE- C HEC K that co upl ing nu t wr e nc he s, di al indica t or s, or o t he r ite m s ha ve been remove d b ef ore rotat ing any shafts.
DO NO T LOOSEN a pa c ki ng gland nu t be for e c he ck in g t h at the nut ha s a pos itive thread enga gement.
!
CAUTION
ah ea d o f
the starter in addition to shutting off
CAUTION
PERIODICALLY INSPECT all valves, fittings, and piping for corrosion, rust, leaks, or da mage .
PROVIDE A DRAIN connection in the vent line near each pressure relief device to prevent a build-up of condensate or rain water.
!
CAUTION

Contents

List of Tables List of Figures Safety Considerations Introduction Abbreviations 17/19EX Machine Familiarization
Machine Identification Label System C omponents Cooler Condenser Moto r-Co m pr e ss o r Control Center Moto r S tarte r Utility Vessel
Contents
Refrigeration Cycle Motor/Oil Ref r ige r ati on Co oli ng Cy c le Hermeti c M achine s ( 19 S eries ) Lu brication Cycle
Summary Deta ils
Open-Dri ve Mach in es (17 Se ries) Lub rica t io n Cycle
Summary Deta ils
Starter s Controls
Definitions
Analo g Signal Digit al Signal Volatile Memory
General PIC System Components
Pr ocessor Module (PSIO ) Starter Management Module (SMM) Loca l Interface De vice ( LID) 6-Pack Relay Board 8-Input Modules Oil Heater Contactor (1C) Oil Pump Contactor (2C) Hot Gas Bypa ss Contactor Relay (3C) (Opti onal) Control Transformers (T1-T4) Control and Oil Heater Volt age Sel ecto r (S1) Oil Differential Pressure/Power Supply Module
Contents
LID Operation and Menus
General Alar m s and Alerts LID Defa ult Screen Menu I tems Menu Structure To View or Cha nge Poi nt S tatus Override Operations To View or Cha nge Time Schedule Opera tion To View and Change Set Points Service Operation
PIC System Funct ions
Capacity Control Enteri ng Chilled Water Contro l
Contents
Deadband Proportional Bands and Gain
Contents
Dema nd Limiting Machine Timers Occupancy Schedule
Safety Controls
Shunt Trip
Def a u lt Scr een Fr eeze Moto r Cooling Control (Herme tic Motors Only) Auxiliary Oil Pump Control (Open-Drive Machines Only) Shaft Seal Oil (Open Drive Machines Only) Ramp Loading Control Capacity Ov erride High Discharge Temperature Cont r ol Oil Sump Temperature Control Oil Cooler Remote Start/ St op Contr ol s
Contents
Spare Safety Inputs Spa re Al ar m Con t ac ts Condenser Pump Control Condenser Freeze Pr evention Tower-Fan Relay Auto. Restart After Power Failure Water/Br ine Reset Demand Limit Control, Option (Requi res Optional 8-Inp ut Module) Surge Prevention Algor ithm Surge Protection Lead/Lag Control
Common Point Sensor Installation Machi ne Communicati on Wir i ng Lead/Lag Operation Faulte d Chi ller Operation
Contents
Load Balancing Auto. Restar t After Power Failure
Ice Build Control
Ice Build Initiation Start-Up/Recycle Operation Tempe rature Control Du ring Ice Build Termination of Ice Build Retu rn to Non-I ce Build Operations
Attach to Network De vice Contro l
Attachi ng to Other CCN Modules
Service Operation
To Log On To Log Off Holida y Scheduling
Contents
Start-Up/Shutdown/Recycle Sequence
Local Star t -Up Shutdown Sequence Automatic Soft St op Amps Threshold Chilled Water Recycle Mode Safety Shutdown
Before Initial Start-Up
Job Data Required Equipment Requi r ed Using the Utility Vessel and Pumpout System Remove Shipping Packaging Open-Drive Motor Electrical Connection Open-Drive Motor Auxiliary Devices Open Oil Circuit Valves
Contents
Torque All Gasketed Joints Check Machine Tightness Ref rigerant Tracer Leak Test Machine Standing Vacuum Te st Machine Dehydration Inspect Water Piping Check Optional Pumpout Compress or Wat er P iping Check Relief Devices Inspect Wiring
Check Insulation Resistance (Hermetic Motor) Check Insulation Resistance (Open-Drive Motor)
Open-Drive Motor Pre-Start Checks Carrie r Comfort Ne twork Inte rface
Contents
Check Starter
Mechanical-T ype Star ters 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 Input the Local Occupied Schedule (OCCPC01S) Input Service Configurations
Password Input Time and Date Change LID Config ur ation If Necessa r y Modify Controller Identi fi cati on If Necessa r y Input Equipment Servi ce Pa r ameters If Necess ary
Modify Equipment Configuration If Necessary Check V oltage Supply Perform an Automated Control Test
Check Pumpout System Controls and Optional Pumpout Compr es sor High Altitude Loca ti ons Charg e Refriger ant into Machine
Trimmi ng Refrigerant Cha r ge
Initial Start-Up
Preparation Manual Operation of th e Guid e Vane s Dry Run to Test Start-Up Sequence Check Ro tation (Open-Drive Motor)
Contents
Check Ro tation (Hermeti c Motor)
If Rotation Is Proper If the Motor Rotation Is Not Clockwise
Contents
Check Oil Pressure and Compressor Stop Calibrate Motor Current Demand Setting To Prevent Accidental Start-Up Hot Alignment Check for Open-Drive Machines Doweling for Open-Drive Machines Check Machine Operating Condition Instruct the Customer Operator
Cool er-Condenser Utility Vessel Pumpout Syst em Motor Compressor Assembly Motor Compressor Lubrication System Control System Auxiliary Equ ipment Describe Machine Cycles
Review Maintenance Safety Devices and Procedures Check Operator Kn owledge Review the Start-Up, Operation, and Maintenance Manual
Operating Inst r uc tions
Operator Duties Prepare the Machine for Start-Up To Start th e M achine Check the Runni ng System To Stop the Machine After Limited Shutdow n Extended Shutdown After Extende d Shut down
Contents
Cold Weather Operation Manual Guide Vane Operation Refrigera ti on Log
Contents
Pump out and Refrigera nt Transfer Pro cedures
Pr epar ation Operating the Optional Pumpout Compressor
To Read Re frige ran t Press u r es
Transferring Refrigerant from Normal Operation into the Utility Vessel Tra n sf err i n g Ref ri ger a n t from No rmal Op eration in to the
Cooler/Con denser/Com pr essor Section Return Refrige rant to Normal Operating Co nditions
Genera l Mai nt e na nc e
Refrigeran t Pro perti es Adding Refri gera n t Removing Refrigerant Adjusting the Refrigeran t Charge Refrigerant Leak Testing Le ak Ra te
Contents
Test After Service, Repair, or Major Le ak
Ref rigerant Tr acer To Press u rize with Dry Ni t rogen
Repair the Leak, Retest, and Apply Standing Vacuum Test Checking Guide Vane Link age Contact Seal Mainte nance (Open-Drive Machi nes)
Seal D isa ssem bly Seal Reassembly
Machin e Alignment (Open-Dri ve Machines )
Align ment Methods Preliminary Alignment Near F in al Al i gnment Final Alignment Hot Al ignment Check Doweling
Weekly Maintenance
Check the Lubrication System
Sched ule d Mai nt e na nc e
Service Ontime Inspect the Co ntro l Center Check Safety and O perating Controls Monthly Changing Oil Filter
19EX Compressors FA Style Compr essor s
Oil Specification Oil Changes
To Change the Oil
Contents
Refrigeran t Filter Oil Reclaim Filter
Contents
Inspect Refrigerant Float System Inspect Relief Valves and Piping Coupling Main tenance (Open-Driv e Machines)
Procedure
Moto r Mainten ance (O p en-Dri ve Machin es)
Cleanliness Sleeve Bearings
Open-Drive Motor Handling/Rigging Open-Drive Motor Storage Com pr e sso r Be arin g and Gear Ma in t enan c e Inspect the Hea t Exchanger Tubes
Cooler Condenser
Water Leaks Water Tre atmen t
Inspect the Starting Equipment Check Pressure Transducers Pumpout System Mai n tenanc e
Optional Pumpout Compressor Oil Charge Pumpout Safe ty Control Settings
Ordering Replacement Chiller Parts
Ope n -Driv e Motor Renewal Parts
Troub le sh ooting Gui de
Overvi ew Checking the Display Messages Checkin g Te mp erat ur e Senso rs
Resistance Check
Contents
Voltage Drop Check Sensor Ac curacy Dual Tempe r ature Sensors
Contents
Checking Pressure Transducers
Oil Differential Pressure/Power Supply Module Cal ib ratio n Troubleshooting Transd uce r s Transducer Replacement
Control Algori thms Checkout Proce dure Control Test Control Modu les
Red LED Green LE Ds
Notes on Module Operation Processor Module (PSIO)
Inputs Outputs
Contents
Starter Management Modul e ( SM M)
Inputs Outputs
Options Modules (8-Input) Replacing Defective Processor Modules
Insta lla ti on of Ne w PSIO Module
17/19EX Physical Data and Wiring Schematics
Compressor Fits and Clearances
Initial S t art - Up Checklist for 17/19EX Centri f ug al Liqui d Chiller

List of Tables

Table 1 — Major PIC Components and Panel Locations Table 2 — LID Scre ens
Example 1 — Status01 Display Scre en Example 2 — Status02 Display Scre en Example 3 — Status03 Display Scre en Example 4 — Setpoint Display Screen Example 5 — Configur ation (Config) Di splay Screen Example 6 — Le ad/Lag C onfig uration Displ ay Screen Example 7 — Service1 Display Screen Example 8 — Service2 Display Screen Example 9 — Service3 Display Screen Example 10 — Maintenance (Main t 01) Di splay Scre en
Contents
Example 11 — Maintenance (Main t 02) Di splay Scre en Example 12 — Maintenance (Main t 03) Di splay Scre en Example 13 — Maintenance (Main t 04) Di splay Scre en
Contents
Table 3 — Protective Safety Limits and Control Settings Table 4 — Capacity O ve r rides Table 5A — HFC-134 a Pressure — Temperature (F ) Table 5B — HFC-134 a Pressure — Temperature (C) Table 6 — Recomm ended Tor que Table 7 — Control Test Me nu Functions Table 8 — LID Prima r y an d Seconda r y Messages and Custom Alarm/
Alert Messages with Troubleshooti ng Gu ides
A. Shutdown with ON/OFF/RE SET-OFF B. Timing Ou t or Ti m ed Out C. In Recycle Shutdown D. Pre-Start Alerts E. Nor mal or AUTO.-RES TART F. Start-U p Fail ur es G. Compressor Jumpstart and Refrigerant Protection
Contents
Table 8 — LID Primar y an d Seconda r y Messages and Custom Alarm/
Alert Messages with Troubleshooti ng Gu ides (Continued)
H. Normal Run with Reset, Temperature, Or Demand I. Normal Run Overrides Active (Alerts) J. Out-of-Range Sen sor Failures K. Machi ne Protect Limit Faults L. Machine Alerts M. Spare Sensor Alert Messages N. Other Problems/Malfun ctions
Table 9A — Thermistor Temperature (F) v s Re sistance/Voltage Drop Table 9B — Thermistor Temperature (C) v s Resistance/Voltage Drop Table 10 — 17/19EX Heat Exchanger, Economi z er/Storage Vessel,
Piping, and Pum pout Unit Weights Table 11 — Addi ti onal Conde nser Weights Table 12 — Com pr essor/Motor/Suction E lbow Wei ghts Table 13 — Addi ti onal Cool er Weights
Contents
Table 14 — Marine Waterbox Cover Weights Table 15 — NIH Waterbox Cover Weights Table 16 — Auxiliary Systems, Electrical Data Table 17 — Open-Dri ve Compressor Fit s a nd Cl ea r anc es Table 18 — Hermetic Compressor Fits and Clearances

List of Figures

Figure 1 — 17/19 EX I den t if ica tion Figure 2 — Typical 17EX Installation Figure 3 — Typical 19EX Installation Figure 4 — Refrige r ant, Motor Cooling, and Oil Cooling Cycles Figure 5 — Hermetic Compressor Lubrication System (EX Compres-
Figure 6 — Open-Drive (17 Series) Lubrication Cycle Figure 7 — 17EX Controls and Sensor Locations Figure 8 — 19EX Controls and Sensor Locations Figure 9 — Control Center (Front View); Shown with Options Module Figure 10— Control Sensors (Temperature)
Contents
sor Shown)
Figure 11— Control Sensors (Pressure Transducer, Typical) Figure 12— Power Panel without Options (Open-Dr ive Mac hi ne
Shown)
Contents
Figure 13— Power Panel with Options (Hermetic Machine Shown) Figure 14— LID Default Screen Figure 15— LID Service Screen Figure 16— 17/19 EX Me n u Stru ct ur e Figure 17— 17/19EX Service Menu Structure Figure 18— Example of Point Status Screen (Status01) Figure 19— Example of Time Schedule Operation Screen Figure 20— Examp le of Set Poi n t Scre en Figure 21— 17/19EX Hot Gas Bypass/Surge Prevention Figure 22— 17/19EX with Default Metric Settings Figure 23— Examp le of Att ach to Netwo rk D evi ce Screen Figure 24— Example of Hol iday Period Screen Figure 25— Control Sequence Figure 26— Typical We t-Bulb Type Vacuum Indicator
Contents
Figure 27— Shipping Bol t on O pen Drive Motor Figure 28— 17/19EX Leak Te st Proc edure s Figure 29— Dehydration Cold Trap Figure 30— Correct Motor Rotation Figure 31— Refriger ation Log Figure 32— Pumpout Arrangement and Valve Number Loca ti ons
(12-ft Vessel Shown) Figure 33— Pumpout Unit Wir ing Schematic (19EX Shown) Figure 34— Optional Pumpout Compressor Figure 35— Electroni c Vane Actuator Linkage Figure 36— Compr essor Contact Seal (Open-Drive Machines) Figure 37— C hecking Prelim inary Alignment Figure 38— Measuring Angular Misalignment in Elevation Figure 39— Measuring Angular Misal ignment on Brackets Figure 40— Alignment Form ula
Contents
Figure 41— Adjusting Angular Misalignment in Plan Figure 42— Correcting Parallel Misalignment Figure 43— Alignment Check — Assembled Coupling Figure 44— Removing the Oil Filter Figure 45— Typical Float Valve Arrangement Figure 46— Lifting Open-Drive Motor Figure 47— Controls for Optional Pumpout Compr essor Figure 48— Oil Differen ti al Pressure /Po w er Suppl y Module Figure 49— PSIO Mod u le LE D Lo cati ons Figure 50— LID Modul e (Rear View) and LED Locations Figure 51— Processor (PSIO) Module Figure 52— Starter Management Module (SMM) Figure 53— Option s Module Figure 54— Model Number Nomenclature for Compressor Size
(See
Figure 1
also)
Contents
Figure 55— Open-Drive Compressor Fit s a nd Cl ea r anc es Figure 56— Hermetic Compressor Fits and Clearances Figure 57— Electronic PIC Controls Wiring Schematic —
H ermetic M achine Figure 58— Electronic PIC Controls Wiri ng Schema tic —
Open-Drive Machine Figure 59— Machine Power Panel, Starter Assembly,
and Motor Wiring Schematic Figure 60— Hermetic Drive — Power Panel with Water-Cooled Oil
Cooler Figure 61— Hermetic Drive — Power Panel with Motor
Cooling Solenoid Figure 62— Open Drive — Power Panel

Introduction

Prior to initial star t-up of the 17/19EX unit , those inv olved in the start-u p, 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 ope r ation.
WARNING
This unit us es a microp rocessor con t rol system. Do not sho rt or jumper betw een ter minatio ns on circuit bo ards or mo du les; contro l o r bo ard 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 con­trol ce nte r .
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.
!
WARNING
WARNING
This eq uipment uses , a nd can r a dia te , r ad io fre qu en cy e ne rg y. If not in sta lled an d used in accordance wit h the ins t ruction manual , i t may cause in t erference to radio communications. It has been tested and found to comply with the limits for a Class A comput ing device pursu ant to Subpart J of Part 15 of FCC Rules, which are de signed t o p rovide reasonab le protection agains t such inte rf erence when operat ed in a co mmerc ial environmen t . Opera t io n of this eq uipme nt in a resi den­tial area is l ik ely to ca use interfere nce, in wh ich case the user, at hi s own expe nse, will be requi red to ta ke whatever mea sures may be requ ired to co rrect the in t erference.
Alw ays stor e and transport replac ement or defecti ve board s in anti - st at ic shi p­ping ba g.
!
WARNING

Abbreviations

Frequently us ed abbreviations in t his m anual in c lude:
CCN Carr ier Comf or t Netw or k LCDW — Leaving Condenser Wa ter CCW Coun terclockwise LCW — Leavi ng Chi lled W ater CHW Chi ll ed W ater LED — Lig ht-Em i tt i ng Di ode CHWR Chi ll ed Water Ret urn LID — Local Inter fac e Devic e CHWS Chilled Water Supply OLTA — Overload Trip Amps CW C lo ckwise PIC — Pr oduct Integr at ed Control ECW Entering Chilled Water PSIO — Processor Sensor Input/Output Module ECDW Ent er ing Condenser Water RLA — Rat ed Load Amps EMS Energy Ma nagem ent Syst em SCR — Silicon Control Rectif ier HGBP Hot Gas Bypass SMM — S tarter Management Module I/O Input/Output TXV — Thermostatic Expansion Valve LCD Liquid Crystal Display
17/19EX Machine Familiarizat ion (Figure 1, F igure 2, and Figure 3)

Machine Identification Label

The ide ntific ation label is located on the ri ght side of t he m ac hine co ntrol center panel. The label contains information on model number, refrigerant charge, rated voltage, etc.

System C omponents

The components include the cooler and condenser heat exchangers in separate vessels, motor-compressor, lubrication package, control center, utility vessel, and motor starter. All connec tion s from pr essur e v es s els have exte r nal thre ads to enable each com pone nt to be pressure te s te d with a thr eaded pipe cap during fac tory ass em bly.
Click here for Figure 1 — 17/19EX Identification
Click here for Figure 2 — Typical 17EX Installation
Click here for Figure 3 — Typical 19EX Installation

Cooler

This ves s el ( als o known as the evapo r ator) is loc ated under neath the cond ens er, next to the utility vessel. The coole r is ma intained at lower tempe r ature/pr essur e s o that evaporating refr igerant c an r em ove heat from water flowing through its inter nal tubes .

Condenser

The condense r oper ates at a higher temperature /pressur e than the cool er , and has water flowing through its intern al tubes in or der to remove heat from the refr igerant.

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 and regulates the machine capac ity as required to main tain pro per leaving chil led water temperature. 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 and how ma ny hours the machine has been running
sequences machine start, stop, and recycle under microprocessor control
provides access to other CCN (Carrier Comfort Network) devices
Motor Starter (Purchased Separately)
The sta r ter allo ws for the pro per star ting and disconnect ing of the electr ic al energy for the
compressor-motor, oil pump, oil heater, and control panels.

Utility Vessel

Duri ng normal operat ion, this v es s el func tions as an ec onomizer, ret ur ning flash gas t o the second stage of the compressor and increasing the efficiency of the refrigeration cycle. During peri ods of shutdown an d s er v ic e, the ut ility ve s s el c an serv e as a s torage tank for the refr igerant .
Ref rigeration Cy cle (
The machine compressor continuously draws large quantities of refrigerant vapor from the cool er , at a rate determ ined by th e am ount of guide va ne openi ng. This c om pr essor s uc tion reduces the pressure within the cooler, allowing the liquid refrigerant to boil vigorously at a fairly low temperature (typically 38 to 42 F [3 to 6 C]).
The liquid refrigerant obtains the energy needed to vaporize by removing heat from the water or brin e in the cooler tubes. The c old water or br ine can then be used in ai r co nditioning and/or other pr ocess es .
After r em ov ing hea t from the water or br ine, the refrige r ant vapor ent er s the first s tage of the compressor, is compressed and flows into the compressor second stage. Here it is mixed with flash-economizer gas and is further compressed.
Figure 4
)
Compr es s ion rais es the refr igerant temperatur e above t hat of the water flowing t hr ough the condens er tub es . When the warm (typically 98 to 102 F [37 to 40 C]) ref r igerant v apor com es into contac t wit h the cond ens er tub es , the relativel y coo l c ondensing water ( typically 85 t o 95 F [29 to 35 C]) remov es s om e of the heat and t he v apor c ondenses into a liquid .
The liq uid refrigerant pass es throu gh an orif ic e into the FLASC chamber. B ec ause th e cool es t conde ns er water is flowing throug h the FLAS C, it is at a lower press ure and part of t he entering li quid ref r igerant will flas h to vapo r , t her eby cooling the remaining liquid. The vapo r is then recondensed by the condenser water flowing through the FLASC chamber.
The subcoole d liquid refri ger ant dr ains into a high-side valve c hamber which meters t he refr igerant liquid into a flash ec onomizer cham ber. Pressure in this ch am ber is intermediate betwe en c onden s er and cooler pres s ur es. At this lowe r pr es s ur e, some of the li quid ref r igerant flashes to ga s , f ur ther cooling the remaining liquid . T he flash gas , havin g abs orbed heat, is returned directly to the compressor second stage. Here it is mixed with discharge gas that is already c om pres s ed by the firs t-st age impeller. S inc e the flash gas has to pas s through only half t he c om press ion cyc le, to reac h c onden s er pr es s ure, there is a sav ings in power.
The cooled li quid ref r igerant in the eco nom iz er is me tered thr ough the low-side valve chamb er into the c ooler. B ec ause pres s ure in t he c ooler is lower t han economizer pr essur e, some of th e liquid flashes and cools the re m ainder t o ev aporat or ( c ooler) tempe r ature. The cycle is now complete.

Motor/Oil Refrigeration Cooling Cycle

The mot or is c ooled by liquid re frigerant taken from the botto m of t he c onden s er v es s el (Figure 4). Flow of refrigerant is mai ntained by the pre s s ur e differ ential that exists due to compressor operat ion. After the re frigerant flo ws pas t an iso lation v alv e, 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 into the motor . On models with a so lenoid valve , t he v alve will ope n if additional m otor cooling is re quired. Once past the orif ic e, the refr igerant is dir ecte d ov er the motor by a s pr ay nozz le.
The ref r igerant coll ec ts in the bottom of the motor casing and then is drained ba ck into the cooler through the motor refrigerant drain line. An orifice in this line maintains a higher pressure in the motor shell than in the cooler/ oil sump. The motor is protected by a tempe r ature sensor imbedded in t he s tator windin gs . On models with a so lenoid va lv e, higher m otor tem perat ur es (above 125 F [51 C]) energize the solenoid to provide additional motor cooling. On all models, a further increase in temperature past the motor override set point will override the temperature capac ity control to hold, and if the motor tem per atur e r is es 10° F (5.5° C) ab ov e this set point, will c los e the inlet guide vanes. If the temperature r is es above t he s afety lim it, th e c om pr essor will s hut down.
On machines wit h E X c om pr es s ors , t he oil is also cooled by liq uid refrigera nt. Refrigera nt that flows to the oil cooling system is regulated by a thermostatic expansion valve. There is
alway s a m inimum flow byp as s ing the TXV , whic h flows thr ough an or ifice. The TXV valve regulates f low into the oil/refri ger ant plate and frame-type he at exchanger. The bulb for the expans ion valv e cont r ols oil tem per atur e to the bearings. The refr igerant leaving the heat exchanger then returns to the cooler.
On machines wit h FA c om pres s or s , the oil is water co oled. Wat er flow through the oil cool er is manu ally adjuste d by a plug valve to mai ntain an operat ing temp er ature at t he r es ervoir of approx im ately 145 F (63 C).
Click here for Figure 4 — Refrigerant, Mo tor Cooling, and Oil Coo ling Cycles

Hermetic Machines (19 Series) Lubrication Cycle

Summary

The compre ssor oil p ump and oil reservoir a re l ocated in the compressor base. Oil is pumped through an oi l c ooler and a filte r to rem ove heat and any forei gn parti c les . Part of t he oil flow is directed to the compressor motor-end bearings and seal. The remaining flow lubricates the compressor transmission, thrust and journal bearings and seal. Oil is then returned to the reservoir to complete the cycle (Figure 5).

Details

Oil is charged into the reservoir (Item 1) through a hand valve (Item 4) which also functions as an oi l dr ain. If there is refrige r ant in the mac hine , a pump is required for cha r ging. Si ght glass es ( It em 10) on the reservoir wall permit obse r v ation of th e oil level. The normal opera ting oil lev el is from the mid dle of the lower sight glass to the to p of the lower sight glass.
The mot or - dr iv en oil pump (I tem 8) disc harges oil to an oil cooler (Item 12) at a rate and pressure controlled by an oil regulator (Item 7). The differential pressure (supply versus return) is register ed at the control ce nter. Oil diffe r ential pr es s ure is m aintained between 18 to 30 psi (124 to 207 kPa) .
The oil pum p disc har ges oil t o the oil co oler (It em 12) . Oil is then piped to the oil filt er assembly (It em 9) . This filter is c apable of being va lv ed closed to per m it removal of the f ilter without draining the entire oil system (see Scheduled Maintenance, Changin g Oil Filt er section for det ails) . T he oil is th en piped to t he oil cooler (Item 12).
The oil co oler on th e E X co m pr es s or is a plate-and-fr am e type, r efrige r ant cool ed, heat excha nger. T he E X c om pr essor oil cooler heat ex c hange r us es r efrige r ant from the conde ns er as a coolant. The refri ger ant co ols the oil to a temper ature between 110 and 12 0 F (43 and 49 C) sup ply oil te m per atur e to the bearings.
The FA compres s or oil cooler heat ex c hange r is water cooled. Th e water flow thro ugh the cool er is m anuall y co ntroll ed by a plug valve. The valve should be adjust ed to main tain approx im ately 145 F (63 C) in the oil s um p during runn ing conditions.
As the oil leaves the oi l c ooler, it passes the oil pre s s ur e transducer (Item 14) and then the thermos tatic ex pansion val v e bulb (Item 13). The oil flow is then div ided, and a portion flo ws to the mot or - end bea r ing (It em 19) and seal. The remaind er lubricates the c om press or transm is s ion (Item 2) and the thrus t and jour nal be ar ings (It em 3) . Thrus t beari ng tempe r ature is indic ated at the Local Interface De v ic e ( LID). Oil from eac h c ir c uit re turns by gr av ity to the reservoir.
A de m i s t e r (Items 17 an d 18) , by c en t rifug al actio n, dr a ws r efr ig erant gas f r om the transmission area to the motor shell. The resulting pressure difference prevents oil in the trans­mission cavity from leaking into the motor shell.
Several saf ety features are part of the lubr ic ation s y stem:
In the ev ent of power fai lur e, a small oil reservoir ( Item 16) s upplie s su ff ic ient oil reser v e to ensure continued lubrication until all compressor parts have come to a complete stop. The bearing temperature sensor (Item 15) monitors thrust bearing temperatures and shuts off the machine if th e temperature r is es above a select ed point. Low-o il pr essur e will shut down the machine or prevent a s tart if oil pressur e is not adequate.
The PIC (Product Integrated Control) measures the temperature of the oil in the sump and maintains t he tempe r ature du r ing shut down (see Contr ols , Oil Sum p Tempe r ature Co ntrol sect ion). This tempe r ature is read on the LID default sc r een.
Duri ng the machine star t-up, the PIC will energize the oil pump and pro v ide 15 seconds of prel ubr icat ion to the bearin gs after the oil pre s s ur e is v er ified and befor e the co ntrols start the compressor. During shutdown, the oil pump will run for 60 seconds after the compressor actually shuts dow n for the pur pose of pos t-lub r ic ation. The oil pump can also be en er gized for testi ng purpos es in control s test.
Ramp loading ca n s low the rate of guide vane op ening t o m inimize 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; oil pr es s ur e falls off, and lubric atio n is poor. If oil pressure fa lls below 15 ps i ( 90 kPa) differential, the PIC will shu t down the compressor.
Oil reclaim is accomplished by returning the system oil through the check valve/orifice (Item
11). A s oil builds up behind the second stag e im pelle r , it is dr ained by the check v alv e/or ifice back in to the oil res erv oir . An oil /refri ger ant mi x ture is drawn up fr om the oper ating lev el of the cooler into the guide vane housing. This assists the oil return system at low load operating conditions.
Click here for Figure 5 — Hermetic Compressor Lubrication System (EX Compres s or Shown)

Open-Driv e M achine s ( 17 S erie s) Lu brication Cycle

Summary

The main oil pum p and oil reser v oir ar e c ontained in the c om press or base. Oil is pumped through an oi l c ooler and a filte r to rem ove heat and any forei gn parti c les . A port ion of the oil is then di r ec ted to s haft-end bearing and the shaft seal. The balanc e of the oil lubr ic ates t he compressor transmis s ion and the t hr us t and jour nal bearings. The beari ng and tran s m is s ion oil returns directly to the reservoir to complete the cycle. Contact-seal oil leakage, however, is coll ec ted in an atmospheric f loat cha m ber to be pum ped back to the main r es ervoir as the oil accumulates .
Deta ils (See
Oil may be charged into the reservoir (1) through a hand valve (2) which also functions as an oil drain. If t her e is refrigerant in th e m ac hine, however, a hand pum p will be r equired for charg ing at this c onnection.
An oil-charging elbow ( It em 20) on the seal-oil retur n c ham ber allows oil to be added without pumping. The seal-oil return pump (Item 21) automatically transfers the oil to the main reservoir. Sight glasses ( Item 6) on the reserv oir wall permit obser v ation of the oil level.
A motor-driven oil pump (Item 5) discharges oil to an oil cooler (Item 7) at a rate and pressure contr olled by an oil regulator ( It em 4) . The dif feren tial oil pr es s ure (bearing suppl y ve r s us oil reserv oir) is r egiste r ed on the co ntrol pa nel.
Figure 6
)
Water flow through the oil cooler is manually adjusted by a plug valve (Item 9) to maintain the oil at an oper ating temperatur e of appr ox im ately 145 F (63 C). Dur ing shutdown, the oi l temperature is also maintained at 150 to 160 F (65 to 71 C) by an immersion heater (Item 3) in order to minimiz e absorption of refr igerant by the oil.
Upon leaving the oil coo ler , the oil is filter ed (11) and a po rtion is directe d to the seal- end bearing (17) and the shaft seal (18). The remainder lubricates the compressor transmission (15) and the thrust an d journal bearings (10). Thrus t bear ing temp er ature is indicat ed by the PI C controls. Oil from both circuits returns by gravity to the reservoir.
A demist er ( 13 and 16 ) , by c entrifugal action, draws refrig er ant gas from the trans m ission area to a housin g that is ve nted to th e c ooler (It em 19). The r es ulting press ur e difference preve nts oil f r om th e transm is s ion cavity fr om leaking into th e s eal.
The ope n c om pr essor dr iv e r equires tha t t he s haft seal (18) be k ept full of lubric ation oil, even when the ma c hine is not oper ating, t o pr ev ent los s of refri ger ant.
If the mac hine is not oper ating and the oil pump has not oper ated dur ing the las t 12 hour s , the control system will automatically run t he oil pump for one minute in order to kee p the con tact seal filled with oil.
IMP ORTANT : If t he control pow er is to be de energi z ed for more t han one day, the machine refrigerant should be pumped over to the utility vessel.

Starters

All st ar ters, whether supplied by Carrier or the cust om er, must meet Car r ier S tarter Specification Z-375. This specifica tion can be obtained from t he Carr ier S ales Representati v e. The purpose of th is s pec ifi c ation is to ensure t he c om patibility of the starter an d the machine. Many styles of compatible start er s ar e av ailabl e, includ ing solid-s tate starters, autotrans former, wye-d elta closed tr ans ition s tarter s , and full voltage start er s .

Contr ols

Definitions

Analo g Signal

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 atur e, gener ating ma ny v alues. )
varie s in pr oportion to t he m onitor ed sourc e. It qua ntifies v alues bet ween

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/of f, high/low, or op en/clo s ed s ignal .)
is a 2-position representation of the value of a monitored source.

Volatile Memory

Vola tile memory
restored.
CAUTI ON
The memory of the P S IO and LI D modules are volatile. If t he batte ry in a modul e is removed or damaged, all programming will be lost.
is memory inc apabl e of being s us tained if power is los t and su bs equen tly
!
CAUTION

General

The 17/19EX herm etic centri fugal liquid chiller contains a m ic r oprocessor - based c ontro l center that monitor s and c ontro ls all operations of the mac hine. The microproces s or co ntrol system matches the cooling capacity of the machine to the cooling load while providing state-of­the-art machine protection. The system controls cooling load within the set point plus the deadband by sensing the leaving chilled water or brine tem perat ur e, and regulat ing the inlet guide v ane via a mec hanically lin k ed ac tuator m otor. The guide va ne is a v ar iable flow prewh ir l assembly that controls the refrigeration effect in the cooler by regulating the amount of refr igerant v apor flo w into the com press or . An increase in guide v ane open ing increases capacity. A decrease in guide vane opening decreases capacity. Machine protection is provided by the proc ess or which monitor s the digital and analog in puts and ex ec utes capacity ov er r ides or saf ety shut downs, if required.
Clic k here for F igure 6 — Ope n-Drive (1 7 Series) Lubricat i on Cycle

PIC System Components

The Product Integrated C ontrol (PIC) is the control system on the machine. See Table 1. The PIC controls the oper ation of the mac hine by monitor ing all op er ating c onditions. The P IC can diagnose a problem and let th e operat or k now what the prob lem is and wha t t o c hec k . It promp tly positions the guide v anes to ma intain leaving chill ed water temperat ur e. 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 inter faced with the Car r ier Comfo r t Network ( CCN) if de s ir ed. It can communicat e with other PIC - equipp ed c hille r s and other CCN devices .
The PIC consists of 3 modules housed inside the 3 major components. The component names and the con trol voltage c ontained in each component are liste d below (also see
Table 1):
control center – all extra low-voltage wiring (24 v or less)
pow er panel – 115 v control voltage – 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 Module (PSIO )

This module contains all of the operating software needed to contro l the machine. The open­drive ma c hines use a differ ent so ft ware pack age wi thin the PS IO than the hermet ic m ac hine s . There are also control hardware differences between the two types of machines. The 19EX uses 3 pressur e transducers and 8 ther m is tors t o s ens e press ur es and t em perat ur es . The 17EX uses 4 pressure transducers and 7 thermistors to sense pressures and temperatures.
These inputs ar e c onnect ed to the PS IO module. The PS IO also pr ov ides output s to t he: guide vane actuator; oil pump; oil heater; hot gas bypass (optional); motor cooling solenoid; and alarm contact. The PSIO communicates with the LID, the SMM, and the optional 8-input modules for user inter face and star ter managem ent.

Starter Management Module (SMM)

This module is loc ated within the star ter cabinet. This m odule initiates 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 safe ty, condens er high press ur e, oil pum p inter lock, motor curr 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 com m unicat ion with the PSI O is lost.

Loca l Interface De vice ( 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 input center for all local machine set point s , sc hedul es , set-u p funct ions, an d optio ns . The LID has a S TO 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 rel ay s loc ated in the con trol cent er . It is energized by the PSIO fo r the oil pum p, oil heater, alar m , optional hot gas bypass relay , and mo tor cooling solenoid (19E X m ac hine s ) on aux ilia r y oil pump (17E X m ac hine s ) .

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 spar e inputs eac h. They ar e used whenev er chil led water r es et, demand reset, or re ading a spare sensor is re quired. The sensors or 4 to 20 mA signals are field- inst alled.
The spare temperature sensors must have the same temperature/resistance curve as the other tempe r ature sensors on this un it. These sensors ar e rate d 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 115 v. It is controlled by the PIC to mai ntain oil tempe r ature du r ing machine shut down.

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 co ntact or to turn on th e oil pump as necess ar y .

Hot Gas Bypa ss Contactor Relay (3C) (Opti onal)

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

Oil Auxiliary Relay (4C)

This relay, supplie d only wit h open-drive mac hines, opens th e oil cooler solenoid va lv e and interlocks the oil pump with the compressor.

Control Transformers (T1-T4)

These t r ans formers are loc ated in the power panel an d c onvert incoming contr ol volt age to eithe r 21 v ac power fo r the PSIO mo dule and options mo dules, or 24 v ac power fo r 3 power panel contactor relays and a control solenoid valve.

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

It is necessar y to use 115 v in c om ing cont r ol power in the power pane l. The switch must be set to t he 115-v pos ition.

Oil Differential Pressure/Power Supply Module

This module, which is located in the control center, provides 5 vdc power for the transducers and LID backlight.
On open - dr iv e machines, this module outputs the difference between two pres s ur e transducer input si gnals. The modul e s ubtract s oil supply press ur e from t r ans m ission sum p
pressure and outputs the diff er ence as an oil diff er ential pr es s ure signal to the PSIO. The PSIO conve r ts this signal to differential oil pre s s ur e. To calibrat e this reading, refer t o th e Troubleshooting Guide, Checking Pressure Transducers section.
Click her e for Figure 7 — 17EX C ont rols a nd Sensor L oca tions
Click her e for Figure 8 — 19EX C ont rols a nd Sensor L oca tions
Click here for Figure 9 — Control Center (Front View); Shown with Options Module
Click here for Figure 10 — Control Sensors (Temperature)
Click here for Figure 11 — Control Sensors (Pressure Transducer, Typical)
Click here for Figure 12 — Power Panel Without Options (Open-Drive Machine Shown)
Click here for Figure 13 — Po wer Panel with Opt ions (Hermetic Machine Shown)
LID Operation and Menus (Figure 14, Figure 15, Figure 16, Figure 17, Figure 18,
Figure 19, and Figure 20)

General

The LID display will automatically revert to the default screen after 15 minutes if no softkey activity takes place and if the machine is no t in the Pum pdown mode (Fig ur e 14 ).
When not in the default screen, the upper right-hand corner of the LID always dis­plays the name of the scr een that you have entered (Figu r e 15).
The LI D m ay be c onfi gur ed in English or SI units, throug h the LID configur ation screen.
Loca l Operat ion — By pressing the LOC A L s oftkey , 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 Schedul e to determ ine machine st ar t and st op times.
CCN Operation — By pressing the CCN softkey, the PIC is now in the CCN operation mode, and the control will ac c ept modi fications from any CCN interface or module (with the pro per author ity), as well as the LID. The PI C will use t he CCN tim e s c hed­ule to determine start and stop times.

Alar m s and Alerts

Alarm ( *) and alert ( !) s tatus ar e indicated on t he Default screen and the S tatus tables . An alarm (*) will shut down the compressor. An alert (!) notifies the operator that an unusual condition has oc c ur r ed. The machine will c ontinue to oper ate when an alert is sh own.
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 inform ation ar e s ent to th e A lar m Histo r y table.
Note:
When an alarm is detected, the LID default screen will freeze (stop updating) at the time of alarm. The freeze enables the oper ator to vi ew the machine co nditions at the ti m e 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.
Clic k here for F igure 14 — LID Default S cre en
Click her e for Figure 15 — LID Serv ice Screen

LID Defa ult Screen Menu I tems

To perform any of the operations described below, the PIC mu s t be power ed up and h av e successfully completed its self test.
The Default screen menu selection offers four options (Status, Schedule, Setpoint, and Servic e). The S tatus m enu allo ws for viewing and lim ited c alibrat ion/m odifi c ation of contro l points and sensors, relays and cont ac ts, and the options board. The Schedule me nu allow s for the viewing and modif ic ation of the Local Contr ol, CCN Contro l, and Ice B uild tim e s c hedule s . Numer ous s et poi nts including B as e Demand Limit, LCW, ECW , and Ice B uild can be adjus ted under the Setpoint menu. The Service menu can be used to revise alarm history, control test, contr ol algo r ithm sta tus, equipment c onfigur ation, equipm ent service, time and da te, attac h to netwo r k , log out of device, controlle r identification, and LID configurat ions. Figure 16 and
Figu r e 17 provide additional informat ion on t he m enu structur e.
Press the MENU softkey to select from the 4 options. To view or change parameters within any menu structure, use the SELECT softkey to choose the desired table or item. The softkey modification choices displayed will depend on whether the selected item is a discrete point, analog point, or an ov err ide point. A t t his point , press the softkey tha t cor r esponds to yo ur configurat ion selection or pr ess the QUIT so ft k ey . If the QUIT sof tkey is depr essed, the configurat ion wil l not be mod ified. Use the following softk ey s to access and select the desired section.

Menu Structure

To perform any of the operations described below, the PIC mu s t be power ed up and h av e successfully completed its self test.
Pres s M E NU to sele c t f r om the four av ailab le options .
CCN LOCAL RESET ME NU
Press the softkey that corresponds to the desired menu structure.
STATUS SCHEDULE SETPOINT SERVICE
Pres s NE X T or PREV IO US to highlight the desi r ed entry.
NEXT PREVIOUS SELECT ENTER
Press SELECT to access the highlighted point.
NEXT PREVIOUS SELECT EXIT
Press QUIT to leave the selected decision or field without saving any changes.
INCREASE DECREASE QUIT ENTER
Or, pr es s E NTER to leave th e s electe d dec ision or field and save c hange s .
INCREASE DECREASE QUIT ENTER
To View or Cha nge Poi nt S tatus (
Point Status is the actual value of all of the temper ature s , pressur es , relays, and ac tuators sense d and cont r olled by the PIC.
1.
On the Menu screen, press STATUS to view the list of Point Status tables.
STATUS SCHEDULE SETPOINT SERVICE
2.
Press NE X T or PREV IOUS to highlight the desired status tabl e. The list 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
Figure 18
)
Click here for Figure 16 — 17/19EX Menu Structure
Click her e for Figure 17 — 17/19E X Service M enu Structure
3. Press SELECT to view the desired Point Status table.
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
For Discrete Points
desi r ed s tate.
— Press START or STOP, YES or NO, ON or OFF, etc. to select the
START STOP RELEASE ENTER
For Analog Points
— Press INCREASE or DECREASE to select the desired value.
INCR EAS E DECR EAS E RELE ASE ENTER
5. Press ENTER to register new value.
INCR EAS E DECR EAS E RELE ASE ENTER

Override Operations

Note: When overriding or changing metric values, it is necessary to hold the softkey down for a
few seconds in or der to se e a v alue change, especially on kilopas c al v alues.
Clic k here for F igure 18 — Example of Point Status Screen (Status01)
To Rem ov e an Override
1. On the P oint St atus table press 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 highligh ted point.
NEXT PREVIOUS SELECT EXIT
3. Press RELEASE to remove the override and return the point to the PIC’s automatic control.
INCR EAS E DECR EAS E RELE ASE 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.
To View or Cha nge Time Schedule Opera tion (
Figure 19
)
1. On the Menu screen, press SCHEDULE .
STATUS SCHEDULE SETPOINT SERVICE
2. Press NE X T or PREV IOUS to highlight one of the fol lowing schedules .
OCCPC01S — LOCAL Tim e S c hedul e OCCPC02S — ICE BUILD Time Schedule OCCPC03-99S — CCN Time Schedule (Actual number is defined in Config table.)
NEXT PREVIOUS SELECT EXIT
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 perio d or ov er r ide that you wish to
change.
NEXT PREVIOUS SELECT EXIT
5. Press S E LE CT to acc es s the highligh ted peri od or ov erride.
NEXT PREVIOUS SELECT EXIT
6.
a. Press INCREASE or DECREASE to change the time values. Override values are in one-
hour inc r em ent s , up to 4 hours.
INCR EAS E DECR EAS E ENT ER E XIT
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 ENTER EXIT
8. Press E X IT to lea v e the peri od or ov erride.
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
10. Holid ay Des igna tion (HOLIDEF 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 Broadcast function in the Brod efs tab le also mus t be enabled for holiday period s to f unc tion.
Click here for Figure 19 — Example of Time Schedule Operation Screen
To View and Change Set P oints (
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
Figure 20
)
water set point); ECW Set Point (entering chilled water set point); and ICE BUILD set point. Only one of the chill ed water se t points c an be acti v e at one time, and the type of set point is activated in the Service menu. ICE BUILD is also activated and configured in the Service menu.
3.
Press NEXT or PREVIOUS to highlight the desired set point entry.
NEXT PREVIOUS SELECT EXIT
4. Press S E LE CT to modify the highl ighted s et point.
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

Service Operation

To view t he m enu-dr iv en programs av ailab le for Serv ic e Oper ation, see Service Operation section. For examples of LID display screens, see Table 2.
Click here for Figure 20 — Example of Set Point Screen
Table 2 — LID Screens
Example 1 — Status01 Display Screen Example 2 — Status02 Display Screen Example 3 — Status03 Display Screen Ex ample 4 — Set point D i sp l ay Screen Example 5 — Configuration (CONFIG) Display Screen 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 Tab le 2 for examples of LID screens. Point names ar e list ed in the Description column. An overview of LID operation and menus is given in Figure 14,
Figu r e 15, Figure 16, Figu r e 17, Fig ure 18, Figure 19, and Figur e 20 .

Capacity Control

The PIC co ntrols the machine ca pac ity by modulating the inlet guide vanes in response t o chil led water temperature c hanges away fro m the may be change d by a CCN networ k device, or is det er m ined by the PIC adding any active chilled water reset to the chilled water
SET POINT (Increase) BAND, PROPORTIONAL DEC (Decrease) BAND (Ent er ing Chi lled Water) GAI N
may be viewed/overridden on the Status table, Status01 selection.
to determine how fast or slow to respond.
CO NTRO L P O INT
. The PIC uses the
, and the
. The
CONT ROL POINT
PROPORTIONAL INC
PROPORTIONAL ECW
CONT ROL POINT

Enteri ng Chilled Water Contro l

If this optio n is enable d, the PIC uses
modulate the vanes instead of
WATER
control opt ion may be v iewed /modified on the E quipment Conf igurat ion table, Config
LEAVING CHILLED WATER
EN TERING CHI LLED WAT E R
temperature.
temperat ur e to
ENTERING CHILLED
table.

Deadband

This is the tolerance on the chilled water/ brine temperature temperatur e goes outside of t he respo ns e unti l it is within toler ance. The PIC may be configured with a 0.5 ° t o 2° F (0.3° t o
1.1° C) deadband.
For exam ple, a 1° F (0.6° C) deadband set ting con trols the water temp er ature within ±0.5° F (0.3° C) of the control poi nt. This may c aus e frequ ent guide 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 th e defau lt setting.
DEADBAND
DEADBAND
may be viewed or modified on the E quipment Service1 table.
, the P IC opens or cl os es the gu ide vanes in
CONT ROL POINT
. If the wate r

Proportional Bands and Gain

Propo r tiona l band is th e r ate at which the guide vane position is cor r ec ted in pr oporti on to how far the chi lled water /bri ne tempe r ature is f r om the contr ol poin t. P r oportional gain determ ines how quic k ly the guide v anes reac t to how quickly the temperat ur e is m ov ing f r om
CONT ROL POINT
The P r opo rtional Band
one for t em perature response above the contr ol point, the oth er for response below the contro l point.
The fir s t t y pe is c alled
.
can be viewed/modified on the LID. There are two response 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 setting 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 default setting is 6.0. I nc r easing either of these settings will cause t he v anes to re s pond slower than a lower setting.
The
PROP OR TI ON AL E CW GA IN
3.0, with a default sett ing of 2.0. Increase th is s etting t o inc r ease guide va ne r es ponse to a change in enter ing chilled water tem per atur e. The proporti onal ban ds 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.
DE M A ND 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 opening of the
COMPRESSOR MOTOR LOAD
or

Machine Timers

The PIC maintains 2 runtime clocks, known as
TIME. 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 compressor run hours. This timer
COMPRESSOR ONTIME
and
SERVICE ON-
SERVICE ONTIME
is
register up to 32,767 hours before it rolls over to zero.
The chiller also maint ains a start-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 tarted. See the Start-Up/Shutdown/Recycle Sequence section for operational information.

Occupancy Schedule

This sc hedule determines when the chiller is either oc c upied or unoccupied.
Each sc hedul e c ons ists of from one t o 8 oc c upied /unoccupied time periods, se t by the operator. These time per iods can be enabl ed to be in effe c t, or not in effe c t, on eac h 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 unoccupie d time period is in eff ec t.
The machine will shut down whe n the schedule goes to UNOCCUPI E D. These s c hedule s can be se t up to foll ow the bu ilding schedule or to be 100% OCCUP IED if the operator wishes. The schedule s als o c an be bypassed by forcing the Start/Stop command on the PIC Status screen to star t. The schedul es als o can be overridden to k eep the unit in an OCCUPIE D m ode for up to 4 hour s , on a one- time ba s is .
Fig u re 19 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. The 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. weeke nd c ool-down schedule.
Note: This schedule is for illustration only, and is not intended to be a recommended schedule
for chiller operation. Whene v er the chiller is in t he LOCAL mo de, the mac hine uses Occupancy Sc hedul e 01. The Ice Build Time Schedule is Schedule 02. When in the CCN mode, Occupancy Schedule
03 is use d.
The CCN schedule number is defined on the Config table in the Equi pm ent Configura tion
table . T he s c hedul e num ber c an c hange to any value from 03 to 99. If this s c hedul e num ber is changed on the Confi g ta ble, the operat or m us t use the A ttach to Network Device table to upload the new number into the Schedule screen. See Fig u r e 17.

Safety Controls

The PIC mo nitors all safe ty c ontro l inputs , and if required, s huts dow n the machine or li m its
the gui de v anes to pr otect the machine from pos s ible da m age from any of the f ollowi ng condition s :
high bearing temp er ature
high m otor winding temperature
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 atur e and transducer faults
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 overlo ad or groun d fault occurs, check the motor for grounded or op en phas es before at t empting a restart.
If the controller initiates a safety shutdown, it displays the fault on the LID with a primary and
a secon dar y m es s age, and energizes an alarm relay in the star ter an d blinks the alarm light on the cont r ol center. The alarm is s tored in m em or y and can be viewe d in the PIC A lar m Histo r y table along with a message for troubleshooting.
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 monitor ed inputs . Safety c ontac t and aler t limits ar e defined in
Table 3. Alarm and alert me s s ages are lis ted in the Troubleshooting Guide section.
!
CAUTION

Shunt Trip

The optional shunt trip func tion of t he P IC is a saf ety trip . T he s hunt 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 procedure but is unsuccessful for 30 seconds, the shunt trip output is energiz ed and ca us es the circ uit br eak er to tr ip off. If ground fault protection has been applied to the star ter, th e gr ound f ault trip will al s o energize the sh unt trip to trip the circuit brea k er .

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 . Know ledge of the oper ating state of th e c hiller at the tim 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 to normal oper ation.

Moto r Cooling Control (Herme tic Motors Only)

Motor te m per atur e is re duc ed by r efrige r ant entering the m otor shell and ev aporat ing. The
refrigerant is regulated by the motor cooling relay. This relay will energize when the compressor is runn ing and mot or temperatur e is above 125 F (51.7 C). The relay 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 essor is operating for m otor cooling; the relay only control s additional refrigerant to the motor.
Note:
An additional motor cooling relay is not required for Hermetic FA style compressors.

Auxiliary Oil Pump Control (Open Drive Machines Only)

The auxiliary oil pump (optional) is controlled by the PIC. During start-up, if the main oil pump
cannot raise pr essur e to 18 psi d ( 124 kPa) , t he auxiliary oil pump wi ll be energized . During compressor operat ion, the auxilia r y oil pum p will be ener gized if the oil pressure fa lls below the
alert t hr es hold (1 8 ps id [124 k P a]). Onc e r unnin g, the auxiliary oil pump will re m ain on until the compressor is turned off and will deenergize with the mai n oil pump af ter the pos t-lu be time peri od.

Shaft Seal Oil Control (Open Drive Machines Only)

All open dr ive m ac hines require t hat the shaft seal be bathed in oi l at all tim es , especially
when the machine is not running. This ensures that refrigerant does not leak past the seal. The PIC control will energize the oil pump for one minute if the oil pump has not operated during the past 12 hours.
It is importa nt to note that if cont r ol powe r is to be turned off for longer than this per iod, the
refr igerant c har ge must be pump ed ov er int o the utility vessel. Be c aus e the oil heater will also be off during this time, stor ing the r efrig er ant will also prev ent re frigerant mi gr ation into the oil.

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 time when the m ac hine is star ted, and t he c hilled water loop ha s to be broug ht down to normal design co nditions . This helps reduce electrical demand charges by slowly bringing the chilled water to control point. Howev er , the to ta l power dr aw during this per iod remains almost unc hange d.
There are 2 meth ods of ramp loadi ng with the PIC. Ramp loadi ng c an be based on chi lled
water tempe r ature or on motor 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 us ed the firs t time the machine is start ed (at commissioning ) . T he lowest temperature ra m p r ate will 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 selecte d) .
2. Motor load ramp load ing compressor motor load increases by an operator-configured rate.
The
TEMP (Temperature) PULLDOWN, LOAD PULL DOWN,
may be viewed /modified on the LID Equ ipm ent Configur ation table, Config t able (s ee T able 2). Motor load is th e default type.
Capacity Ov erride (See
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.
limits th e r ate at whic h either leaving chill ed water or enterin g
limits the rate at which the compressor motor current or
and
SELECT RAMP TYPE
Table 4
)
2. The vanes are c losed until condition decreases below the first step set po int, and then the
vanes are released to normal capacity control.
Whene v er the mot or c ur r ent dema nd limit se t point is r eac hed, it activ ates a capacity 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 reached, the contr oller normally will only ho ld the guide vanes from opening. If s o equipp ed, the hot gas by pass v alv e will open inst ead of holding the vanes .

High Discharge Temperature Cont r ol

If the disc harge temp er ature inc r eases above 200 F (93 C), the guide v anes are propor tion ally opened to incr ease gas flow throug h the compressor . If the leav ing chille d water temperatur e dr ops 5° F (2 .8° C) below the co ntrol po int temper atur e, machine will enter the recycle mode.
Click here for Table 3 — Protective Safety Limits and Control Settings
Click here for Table 4 — Capacity Overrides

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 efrig er ant temperat ur e. If the difference bet ween t hes e 2 temp er ature s is 50 F (27. 8 C) or les s , the s ta r t-up will be delay ed until the oil tempe r ature is 50 F (27.8 C) or more. On c e this tem per atu r e is c onfirmed, the star t-up co ntinues .
The oil heater relay is energized when ev er the chi ller com pr es s or is off and the oil s um p temperatur 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 temperature plus 70° F (39° C). The oil heater is tu rn ed off when the oil sump temperatur e is eithe r 1) mor e than 160 F (71.1 C) ; or 2) the oil s um p tempe r ature is mor e than 155 F (68. 3 C) and mor e than the coole r re frigerant temperatur e plus 75° F (41. 6° C). The oil heate r is always off dur ing start- 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 ha s oc c ur r ed for more than 3 hour s ( i.e., initial start-up), the compressor guide vane opening will be slowed down to prevent excessive oil foaming that may result from refrigerant migration into the oil sump during the power failure. The vane opening will be slow ed to a valu e of 2° F (1.1 ° C) per minute with temper ature ramp loading.

Oil Cooler

The oil must be cooled when the compressor is running.
EX Compressors: This is accomplished through a small, plate-type heat exchanger. The heat excha nger uses liquid conde ns er r efrig er ant as the c oolin g liquid . A r efrige r ant therm os tatic expansion valve (TXV) regulates refrigerant flow to control oil temperature entering the bearings. T her e is always a flo w of refri ger ant by pas s ing the TXV. The bulb for the expa ns ion valve is str apped to t he oil supply line leav ing the heat exchanger and the val v e is s et to maintain 110 F (43 C).
Note:
valve is manually set to maintain proper temperatures. Set the valve to maintain 145 F (63 C) oil sump temperatures while the compressor is running.
The expansion valve is not adjustable. Oil sump temperature may be at a lower tempera­ture.
FA Compressors: The oil cooler is a water cooled, tube-in-shell type heat exchanger. A plug

Remote Start/ St op Contr ol s

A remote device, such as a timeclock which uses a set of contacts, may be used to start and stop th e m ac hine. However, the device should no t be programmed t o s tart and s top 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 Failur e is not activ ated when a pow er failur e oc c ur s , and the remot e c ontac t is c losed, the machine will indicate an alarm because of the loss of vo ltage.
The cont ac ts fo r Rem ote Star t are wired into th e s tarter at t er m inal st r ip TB5, term inal s 8A and 8B. See the ce r tified dr awin gs fo r furthe r details on c ontact r atings . T he c ontac ts m us t be dry (no power).

Spare Safety Inputs

Norma lly c los ed (NC) digital inpu ts for add itional field- s uppli ed s afeties may be wired to the spare pr otect iv e limit s input cha nnel in pl ac e of the fa c tory installed jumper. (Wi r e m ultiple input s in s er ies.) The opening of any c ontac t will result in a safety sh utdown and LID dis play. Refer to the cer tified drawi ngs for saf ety cont ac t ratings .
Anal og tempe r ature sensors ma y als o be add ed to the opt ions modules, if installed. These may be programmed to cause an alert on the CCN network, but will not shut the machine down.

Spa re Al ar m Con t ac ts

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

Condenser Pump Control

The machine will moni tor the pressure becomes too high whenever the compressor is shut down.
PRESSURE OVERRIDE
Equipment Service1 LID table and has a default value (T able 4). If the
PRESSURE
is greater than or equal to the
is used to determine this pr essur e point. This va lue is fou nd on the
CONDENSER PRESSURE
CONDENSER PRESSURE OVERRIDE
ENTERING CONDENSER WATER TEMP (Temperature)
condens er pump will energi z e to try to dec r ease th e pr es s ure. The pump wi ll turn off when the condenser pressure is less than the pressure override less 5 psi (34 kPa), or the
REFRIG (Refrigerant) TEMP
temperature.
is within 3° F (2° C) of the
and may turn on t his pump if the
CONDENSER
CONDENSER
, and the
is less than 115 F (46 C), then the
CONDENSER
ENTERING CONDENSER WATER

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 exc ept whe n it is either ac tive ly in pumpdown or in Pu m pdown Lo c k out with t he freeze prevention disabled (refer to Control Test table, Pumpdown/Terminate Lockout tables).
When the
POINT
, or the
CONDENSER REFRIG TEMP
is less than or equal to the
ENTERING CONDENSER WATER
CONDENSER FREEZE
temperature is less than or eq ual to the
CONDENSER FREEZE POINT
, then the
CONDENSER WATER PUMP
shall be energized until the 5° F (2.7° C). An alarm will be generated if the machine is in is ener giz ed. An aler t wil l be generated if the machine is not in pump is ener gized. If in rec y c le s hutdown, the m ode shall trans ition to a non-recycle s hutdown.
CONDENSER REFRIG TEMP
is greater than the
CONDENSER FREEZE POINT
PUMPDOWN
PUMPDOWN
mode and the pump
mode and the
plus

Tower-Fan Relay

This control can be used to assist the condenser water temperature control system (field supplied). Low con denser water tem perat ur e c an cause the chi ller to shut down on low refr igerant temperature. The tow er fan rela y , located in the star ter, is c ontrol led by the PIC to energiz e and de energiz e as the pr es s ur e different ial between cooler an d c ondenser vess els changes in order to prevent low c onden s er water tem perat ur e and to ma x im iz e machine effi c iency. T he tower - fan rela y ca n only acc om plish t his if the relay has been add ed to the cool ing tower temperature c ontrol ler . The
CONDENSER WATER PUMP
and condenser pr ess ur e is m or e than 30 ps id (207 kPad) or enteri ng c onden s er water temperatur e is gr eate r tha n 85 F (29 C). The condens er pump is off, f low is lost, the evapora tor refrigera nt temper ature is les s than the
is run ning, flo w is v er ifie d, and the difference be tween co oler
TOWER FAN RELAY
TOWER FAN RELAY
is turned on whe nev er the
is deenergized when the
override tem perat ur e, or the differential pr essur e is less than 28 psid (193 kPad) and enterin g condensing water is less than 80 F (27 C).
IMPORTANT: Afield-supplied water temperature control system for condenser wate r s hould be ins t a lle d. The sys t em should m a inta in th e le av in g co nde ns e r wa ter temperatu re at a t emperat ure that is 20° F (11° C) above the leaving chilled water temperatu re.
CAUTI ON
The tower-fan relay control is not a substitute for a condenser water temperature control. Wh en used with a Water Temperature Control system, the tower fan relay control can be used to help prevent low condenser water temperatures and as so ci ate d pr obl em s .
!
CAUTION

Auto. Restart After Power Failure

This opt ion may be enabl ed or disabled, and may be viewed/m odified in the Config table of Equipment Configuration. If enabled, the chiller will start up automatically after a single cycle drop- out, low, high, or loss of voltage has occ ur r ed, and the power is within ±1 0% of normal. The 15-min start-to-start timer and the stop-to-start timer are ignored during this type of start-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. Auto rest ar t will th en c onti nue like a normal start- up.

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 Poin t t em perature on the Status01 table indi c ates the m ac hine’ s cu r r ent reset temperatur e.
To acti v ate a reset type, input all configurat ion infor m ation for that reset ty pe in th e Config table . T hen inpu t t he r es et ty pe number in the
1.
Rese t Typ e 1 rese t based on a 4 to 20 mA input s ignal. 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 ha r dwired into the num ber one 8-inpu t module .
If the 4- 20 mA si gnal is externa lly powered from the 8-inp ut modul e, the signal is wired 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 wir ed to J1-7(+ ) 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.
Rese t Typ e 2 reset based on a remote temperature sensor input. This type permits ±30° F (±16° C) of
(Requir es opti onal 8-input module) — A utomatic c hilled water tem per atur e
(Requir es opti onal 8-input module) — A utomatic c hilled water tem per atur e
SELECT/ENABLE RESET TYPE
input line.
auto m atic res et to the se t po int based on a temperat ur e s ensor wir ed to the numbe r one 8­input m odule (s ee wiring diagr am s or c er tified drawi ngs ) .
The t em perat ur e s ensor m us t be wire d to termi nal 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 reset will occur. The n, enter the maxi mum amount of re set required t o oper ate the machine. Reset Type 2 can now be activated.
3. Rese t Typ e 3 diff er ence. This typ e of reset will add ±30° F (±16° C) bas ed on the temperature difference betw een enter ing and leavi ng c hille d water tem perat ur e. This is the only type of reset available withou t t he need of the numb er one 8-input module. No wir ing is required 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 differenc e (the differenc e betw een enter ing and leavi ng c hille d water) at which no t em perat ur e r es et occurs. This chi lled water tempe r ature di ff er ence is us uall y the full design lo ad tempe r ature difference. The difference in ch illed wa ter temp er ature at which the full am ount 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 entered . Reset Type 3 can now be activated.
— Automatic chilled water temperature reset based on cooler temperature

Demand Limit Control, Option (Requi res Optional 8-Inp ut 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 with 4 mA and an operator c onfigur 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 , t he s ignal is wir ed to term inals J1- 3(+) and J 1- 2(–). When enabled, the co ntrol is s et for 100% demand with 4 mA and an ope r ator conf igured 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 ac tion. Lif t is defined as th e difference bet ween the pressure at the impel ler ey e and the im pell er dis c harge. The maximum lift tha t a partic ular impeller wheel can perfor m va r ies with the gas flow ac r oss the impel ler , and the size of the wheel.
The alg or ithm f ir s t de termines if corr 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/ P 2) . These points hav e default settings as defined on the Service1 table, or on Table 4. These settings and the algorithm function are graphically displayed in Figure 21 and
Figu r e 22. The 2 sets of load points on this graph (default se tt ings are s hown) descr ibe a line
which the algorithm uses to determine the maximum lift of the compressor. Whenever the actual diff er ential pr essur e between the co oler and conden s er , and the t em perat ur e difference betwe en the en te r ing and le av ing chilled water are above the line on the graph (a s defined by the MINIMUM and MAXIMUM Lo ad Points) the algorithm will go in to a co rrective action mode. If the act ual values are below the line, the algor ithm tak es no acti on. Modi ficat ion of the default set points of the MINIMUM and MAXIMUM load points is described in the Input Service
Configurations section.
Corre c tive action can be taken by ma ki ng 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, Capacity Overrides. B oth of the s e c or r ec tive ac tions wi ll r educe t he lift exper ienced by the compressor and hel p to prevent a surg e c ondition. Surge is a condition when the lift becomes so high that the gas flow across the impeller reverses. This condition can eventuall y caus e m ac hine damag e. The sur ge pr event ion alg or ithm is intended to not ify the operator th at machine oper ating co nditions ar e marginal, and to take ac tion, such as lowering entering condenser water temperature, to help prevent machine damage.

Surge Protection

Surging of th e c om pr essor c an be deter m ined by t he P IC through ope r ator conf igured settings. S ur ge will ca us e am perage fluctuations of the compres s or motor. The PIC monitors these amperage swings, and if the swing is greater than the configurable setting in one second, then one surge count has occurred. The and configured on the Service1 screen. It has a default setting of 25% amps,
PROTECTION COUNTS
A surge protec tion shutdown of the machine will oc c ur whenever t he s ur ge prot ec tion counter reaches 12 counts within an operator specified time, known as the
PERIOD
has a default of 2 minutes .
. The
SURGE TIME PERIOD
can be mo nitore d on the Maint03 t able.
SURGE DELTA PERCENT AMPS
is displayed and configured on the Service1 screen. It
setting is displayed
SURGE
SURGE TIME
Click here for Figure 21 — 17/19EX Hot Gas Bypass/Surge Prevention
Click here for Figure 22 — 17/19EX With Default Metric Settings

Lead/Lag Control

Lead/Lag is a control system process that automatically starts and stops a lag or second chiller in a 2-chiller water system. Refer to Figure 16 and Figure 17 for menu, table, and screen selec tion in fo r m ation . O n m ac hines t hat have PSI O software with Lead/Lag capability, it is possible to ut ilize t he P IC contr ols to pe r form the lead/lag function on 2 mac hine s . A th ir d 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 configuration is viewed and edited under Lead/Lag in the Equipment Configura­tion t able (located in the Service menu). Le ad/lag s tatus dur ing machine op er atio n 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 soft war e capable of performing the lead/lag function
water pumps M US T be ener giz ed fro m the PIC con trols
water flows sh ould be constant
CCN Time Schedules f or all machines mus t be identical
Operat ion Features:
2 chiller le ad/lag
addition of a thir d chiller fo r bac k up
manu al r otation of lead chiller
load balancing if c onfigur ed
staggered restart of the chillers after a power failure
chillers may be pipe d in parallel or in se r ies c hille d water flow

Common Point Sensor Installation

Lead/ lag operation does not r equire a com m on chilled water poin t sensor. Common point 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 lea v ing chilled water sensor of the upstrea m ch iller mus t be moved into the lea v ing chilled wa te r pipe of the downst r eam chiller.
chil led water s ens or should be in s talled. If this se ns or is not ins talled, the return chilled water senso r of t he downst r eam ch iller mus t be relo c ated to th e r eturn chilled water pi pe of the upstream machine.
parallel, the water flow through the shutdown chillers must be isolated so that no water by-pass around the operating chiller occurs. The common point sensor option must not be used if water bypas s ar ound the operating ch iller is oc c ur r ing.
If the common point sensor option is chosen on a chilled water system, both machines should have th eir own 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 poin t sensor for cont r ol, when that mac hine 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 ser ies, a comm on point se ns or s hould be use d. If a common point
If ret ur n c hille d water control is re quired on chill er s piped in se r ies , the com m on poin t return
To properly control the common supp ly point temperat ur e sensor when chiller s ar e piped in

Machi ne Communicati on Wir i ng

Refer to the machine’s Installation Instructions and Carrier Comfort N etwork Interface section for information on machine communication wiring.

Lead/Lag Operation

The PIC co ntrol provides the ability to operat e 2 c hillers in the LE A D/LAG mo de. It also provides the additional ability to start a des ignated stan dby c hille r when either the lead or lag chil ler is faulted and ca pac ity require m ents are not met. The lead/lag option oper ates in CCN mode only . If any other ch iller configur ed for le ad/lag is s et to the LOCA L or OFF modes, it will be unavailable for lead/lag operation.
Note:
Lead/Lag Chiller Configuration and Operation
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 hille r is co nfigur ed to a value of ‘‘3.’’ A value of ‘‘0’’ disables the lead/lag in that chill er .
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.
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 ta ble in th e Contro l A lgorit hm S tatus table.
The conf igured lead chiller is identif ied when the LEAD/L A G SE LE CT valu e for that chiller is
To configure the LAG ADDRESS value on the LEAD/LAG Configuration table, always use
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 th e LE A D/LAG CONFIGURATION and CURRE NT MODE field s .
The lea d c hiller r es pond s to normal start/stop con trols suc h as oc c upan c y schedule, forc ed start/ s top, and remote star t contac t inputs. After c om pleting start up and ramp loading, th e P IC 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 atur es alone, then the operating lag ch iller is s topped.
If the lead chiller is stopped 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 topped. If the co nfigur ed lead chiller stops for and alar 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 lag c hiller.
If the config ur ed lead ch iller does not co m plete the start- up befor 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 chill er then mon itors th e s tart req ues t from the acting lead chiller to start. The PRESTART FAULT TIMER is initiated at the time of a start request. The PRESTART FAULT TIMER’s function is to pr ov ide a tim eout in the event that the r e is a pr es tart alert condition prev enti ng the machine from s tarting in a tim ely m anner. The timer is c onfigur ed under Lead/ Lag, found in the Equipment Conf igurat ion table of the Ser v ice menu.
If the lag chill er does not achie v e s ta r t-up bef or e the PR E S TART FAULT TIMER elapses, then the lag chiller shall be stopped and the standby chiller will be re queste d to start, if configured and ready.
Standby Chiller Configuration and Operation
The conf igured stan dby c hille r is id entified as such by having the LEA D/LAG SELECT configured to the value of ‘‘3.’’ The standby chiller can only operate as a replacement for the lag chil ler if one of t he other two chill er s is in an alarm ( *) c ondition (as s hown on the LID panel). If both le ad and lag ch illers ar e in an ala r m (* ) conditi on, the standby ch iller shall default to operate in CC N mo de based on its configured Occup anc y S c hedule and r em ote co ntacts input.
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