Daikin MicroTech III User manual

WATER-COOLED SCREW CHILLER
MICROTECH III and MICROTECH 4
REV
02
Date
05/2021
Supersedes
D–EOMWC00A07-16_01EN
CONTROL PANEL OPERATING MANUAL
D–EOMWC00A07-16_02EN

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Table of Contents
1INTRODUCTION.................................................................................................................................... 4
2CONTROLLER OPERATING LIMITS.................................................................................................... 5
3CONTROLLER FEATURES .................................................................................................................. 5
4GENERAL DESCRIPTION..................................................................................................................... 6
4.1 GENERAL DESCRIPTION .................................................................................................................... 6
4.2 OPERATION COMMANDS LAYOUT ....................................................................................................... 6
4.3 CONTROLLER DESCRIPTION............................................................................................................... 7
4.4 CONTROL NETWORK DETAILS............................................................................................................10
5SEQUENCE OF OPERATION ..............................................................................................................11
6CONTROLLER OPERATION ...............................................................................................................14
6.1 MICROTECH INPUTS/OUTPUTS..........................................................................................................14
6.2 EXTENSION I/O COMPRESSOR #1 TO #3............................................................................................14
6.3 I/O EXV CIRCUIT #1 TO #3...............................................................................................................15
6.4 EXTENSION I/O FAN MODULE CIRCUIT #2..........................................................................................16
6.5 EXTENSION I/O FAN MODULE CIRCUIT #3..........................................................................................16
6.6 EXTENSION I/O UNIT HEAT PUMP (OLD VERSION)..............................................................................16
6.7 EXTENSION I/O UNIT HEAT PUMP (NEW VERSION)..............................................................................16
6.8 SETPOINTS......................................................................................................................................16
7UNIT FUNCTIONS................................................................................................................................17
7.1 CALCULATIONS................................................................................................................................17
7.2 UNIT MODEL....................................................................................................................................17
7.3 UNIT ENABLE...................................................................................................................................17
7.4 UNIT MODE SELECTION....................................................................................................................17
7.5 UNIT CONTROL STATES....................................................................................................................18
7.6 UNIT STATUS...................................................................................................................................19
7.7 ICE MODE START DELAY..................................................................................................................19
7.8 EVAPORATOR PUMP CONTROL..........................................................................................................19
7.9 CONDENSER PUMP CONTROL...........................................................................................................20
7.10 CONDENSATION CONTROL................................................................................................................20
7.11 LEAVING WATER TEMPERATURE (LWT) RESET..................................................................................22
7.12 UNIT CAPACITY CONTROL ................................................................................................................23
7.13 UNIT CAPACITY OVERRIDES..............................................................................................................25
7.14 ENERGY SAVING MODE....................................................................................................................26
7.15 DAIKIN ON SITE................................................................................................................................26
8CIRCUIT FUNCTIONS..........................................................................................................................27
8.1 CALCULATIONS................................................................................................................................27
8.2 CIRCUIT CONTROL LOGIC.................................................................................................................28
8.3 CIRCUIT STATUS..............................................................................................................................29
8.4 COMPRESSOR CONTROL..................................................................................................................29
8.5 PRESSURECONDENSATION CONTROL................................................................................................31
8.6 EXV CONTROL................................................................................................................................32
8.7 LIQUID INJECTION ............................................................................................................................33
9SOFTWARE OPTIONS.........................................................................................................................34
9.2 INSERTING THE PASSWORD IN A SPARE CONTROLLER.........................................................................34
10 ALARMS AND EVENTS.......................................................................................................................36
10.1 ALARM LOGGING..............................................................................................................................36
10.2 SIGNALING ALARMS .........................................................................................................................36
10.3 CLEARING ALARMS ..........................................................................................................................36
10.4 UNIT RAPID STOP ALARMS ...............................................................................................................37
10.5 UNIT PUMPDOWN STOP ALARMS.......................................................................................................41

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10.6 UNIT EVENTS ..................................................................................................................................43
10.7 CIRCUIT ALARMS.............................................................................................................................46
10.8 CIRCUIT RAPID STOP ALARMS ..........................................................................................................47
10.9 CIRCUIT PUMPDOWN STOP ALARMS..................................................................................................57
10.10 CIRCUIT EVENTS..........................................................................................................................60
11 BASIC CONTROL SYSTEM DIAGNOSTIC..........................................................................................63
12 USING THE CONTROLLER .................................................................................................................65
12.2 NAVIGATING....................................................................................................................................66
13 OPTIONAL REMOTE USER INTERFACE............................................................................................73
14 EMBEDDED WEB INTERFACE ...........................................................................................................75
15 CONTROLLER MAINTENANCE ..........................................................................................................76
16 ICM AND MASTER/SLAVE ..................................................................................................................76

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1 INTRODUCTION
This manual provides setup, operating, troubleshooting and maintenance information for the DAIKIN Water Cooled Chillers
listed below with 1, 2 and 3 circuits using Microtech III and Microtech 4 Controllers (Microtech in the following sections to
be intended as the two mentioned controllers; this manual does not apply to the previous Microtech controllers).
HAZARD IDENTIFICATION INFORMATION
DANGER
Dangers indicate a hazardous situation which will result in death or serious injury if not avoided.
WARNING
Warnings indicate potentially hazardous situations, which can result in property damage, severe personal injury, or
death if not avoided.
CAUTION
Cautions indicate potentially hazardous situations, which can result in personal injury or equipment damage if not
avoided.
Software Version: This manual covers EWWD G-EWLD G-EWWD I-EWLD I-EWWD J-EWLD J-EWWQ B units. The
unit’s software version number can be viewed by selecting the “About Chiller” menu item accessible without password.
Then, pressing the MENU key will return to the Menu screen.
WARNING
Electric shock hazard: can cause personal injury or equipment damage. This equipment must be properly grounded.
Connections to, and service of, the MicroTech control panel must be performed only by personnel who are
knowledgeable in the operation of this equipment.
CAUTION
Static sensitive components. A static discharge while handling electronic circuit boards can cause damage to the
components. Discharge any static electrical charge by touching the bare metal inside the control panel before
performing any service work. Never unplug any cables, circuit board terminal blocks, or power plugs while power is
applied to the panel.
NOTICE
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance
with this instruction manual, can cause interference to radio communications. Operation of this equipment in a
residential area can cause harmful interference, in which case the user will be required to correct the interference at
the user’s own expense. Daikin disclaims any liability resulting from any interference or for the correction thereof.
!
!
!
!
!

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2 CONTROLLER OPERATING LIMITS
Operation (IEC 721-3-3):
•Temperature -40...+70 °C
•Restriction LCD -20… +60 °C
•Restriction Process-Bus -25….+70 °C
•Humidity < 90 % r.h (no condensation)
•Air pressure min. 700 hPa, corresponding to max. 3,000 m above sea level
Transport(IEC 721-3-2):
•Temperature -40...+70 °C
•Humidity < 95 % r.h (no condensation)
•Air pressure min. 260 hPa, corresponding to max. 10,000 m above sea level.
3 CONTROLLER FEATURES
Readout of the following temperature and pressure readings:
•Entering and leaving chilled water temperature
•Saturated evaporator refrigerant temperature and pressure
•Saturated condenser refrigerant temperature and pressure
•Outside air temperature
•Suction line, and discharge line temperatures −calculated superheat for discharge and suction lines
•Oil pressure
Automatic control of primary and standby chilled water pumps. The control will start one of the pumps (based on lowest
run-hours) when the unit is enabled to run (not necessarily running on a call for cooling) and when the water temperature
reaches a point of freeze possibility.
Two levels of security protection against unauthorized changing of setpoints and other control parameters.
Warning and fault diagnostics to inform operators of warning and fault conditions in plain language. All events and alarms
are time and date-stamped for identification of when the fault condition occurred. In addition, the operating conditions that
existed just prior to an alarm shutdown can be recalled to aid in isolating the cause of the problem.
Twenty-five previous alarms and related operating conditions are available.
Test mode allows the service technician to manually control the controllers’ outputs and can be useful for system checkout.
Building Automation System (BAS) communication capability via LonTalk, Modbus, or BACnetstandard protocols for
all BAS manufacturers.
Pressure transducers for direct reading of system pressures. Preemptive control of low evaporator pressure conditions
and high discharge temperature and pressure to take corrective action prior to a fault trip.

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4 GENERAL DESCRIPTION
The control panel is located on the front of the unit at the compressor end. There are three doors. The control panel is
behind to left-hand door. The power panel is behind the middle and right-hand doors.
4.1 General Description
The MicroTech control system consists of a microprocessor-based controller and a number of extension modules, which
vary depending on the unit size and conformation. The control system provides the monitoring and control functions
required for the controlled, efficient operation of the chiller.
The operator can monitor all critical operating conditions by using the screen located on the main controller. In addition to
providing all normal operating controls, the MicroTech control system will take corrective action if the chiller is operating
outside of its normal design conditions. If a fault condition develops, the controller will shut a compressor, or the entire
unit, down and activate an alarm output.
The system is password protected and only allows access by authorized personnel. Except that some basic information
is viewable and alarms can be cleared without a password. No settings can be changed.
4.2 Operation Commands Layout
Figure 1, Operation Commands
Unit On/Off Switch
#1 Compressor
On/Off Switch
#2 Compressor
On/Off Switch
Heat/Cool Switch

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Figure 2, Operation Commands
4.3 Controller Description
4.3.1 Hardware Structure
The MicroTech control system for water cooled screw chillers consists of a main unit controller with a number of extension
I/O modules attached depending on the chiller size and configuration.
Up to two optional BAS communication modules may be included on request.
An optional Remote Operator Interface panel may be included, connected with up to nine units.
Unit On/Off Switch
#1 Compressor On/Off Switch
#2 Compressor On/Off Switch
Unit On/Off Switch
#1 Compressor On/Off Switch
Heat Pump Switch

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Figure 3, hardware structure
4.3.2 System Architecture
The overall controls architecture uses the following:
•One Microtech main controller
•I/O extension modules as needed depending on the configuration of the unit
•Optional BAS interface as selected
Communication Cards
BACnet/IP
BACnet/
MSTP
MODbus
LON
Remote Operator Interface
MicroTech III Unit Controller
Extension I/O Modules
AWC

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Figure 4, System Architecture

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4.4 Control network details
Peripheral Bus is used to connect I/O extensions to the main controller.
Controller/
Extension Module
Siemens Part Number
Address
Usage
Unit
POL687.70/MCQ
POL688.80/MCQ
n/a
Used on all configurations
Comp. #1
POL965.00/MCQ
2
EEXV #1
POL94U.00/MCQ
3
Comp. #2
POL965.00/MCQ
4
Used when configured for 2
EEXV #2
POL94U.00/MCQ
5
Fan#2
POL945.00/MCQ
6
Comp. #3
POL965.00/MCQ
7
Used when configured for 3
EEXV #3
POL94U.00/MCQ
8
Fan#3
POL945.00/MCQ
9
HP
POL925.00/MCQ
25
Heat Pump Option (old version)
HP
POL945.00/MCQ
26
Heat Pump Option (new version) +
Leak detector + Marine version.
Communication modules
The new Microtech 4 has the possibility to offer Modbus RTU and Bacnet (MSTP or IP) communications integrated in the
controller. To activate this feature a specific procedure is used to activate them. This procedure will ask for an activation
key to be entered as a setpoint. This will be done in the factory as part of the unit manufacturing or in the field by asking
for the activation code as a Spare part. Because these features may conflict with others (for example Bacnet IP and Daikin
on Site).
Any of the following modules can be connected directly to the left side of the main controller to allow a BAS interface to
function.
Module
Siemens Part Number
Usage
BacNet/IP
POL908.00/MCQ
Optional
Lon
POL906.00/MCQ
Optional
Modbus
POL902.00/MCQ
Optional
BACnet/MSTP
POL904.00/MCQ
Optional

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5 SEQUENCE OF OPERATION
Figure 5, Unit Sequence of Operation (see Figure 9 for circuit sequence of operation)
Is unit enabled?
Is flow present?
Evaporator pump output on
Wait for chilled water loop to
recirculate.
Yes
Yes
No
Unit power up
Unit in Off state
No
The chiller may be disabled via the unit switch, the remote switch, the keypad
enable setting, or the BAS network. In addition, the chiller will be disabled if all
circuits are disabled, or if there is a unit alarm. If the chiller is disabled, the unit
status display will reflect this and also show why it is disabled.
If the unit switch is off, the unit status will be Off:Unit Switch. If the chiller is
disabled due to network command, the unit status will be Off:BAS Disable. When
the remote switch is open, the unit status will be Off:Remote Switch. When a unit
alarm is active, the unit status will be Off:Unit Alarm. In cases where no circuits
are enabled, the unit status will be Off:All Cir Disabled. If the unit is disabled via
the Chiller Enable set point, the unit status will be Off:Keypad Disable.
If the chiller is enabled, then the unit will be in the Auto state and the evaporator
water pump output will be activated.
After establishing flow, the chiller will wait some time to allow the chilled water loop
to recirculate for an accurate reading of the leaving water temperature. The unit
status during this time is Auto:Evap Recirc.
The chiller will then wait for the flow switch to close, during which time the unit
status will be Auto:Wait for flow.
Is low ambient lockout
active?
Yes
No
Low ambient lockout will prevent the chiller from starting even if it is otherwise
enabled. When this lockout is active, the unit status will be Off:Low OAT Lock.
Is there enough load to
start chiller?
No
Keep pump output on while
chiller is enabled and either
running or ready to run.
The chiller is now ready to start if enough load is present. If the LWT is not higher
than the Active Setpoint plus the Start Up Delta T, the unit status will be Auto:Wait
for load.
If the LWT is higher than the Active Setpoint plus the Start Up Delta T, the unit
status will be Auto. A circuit can start at this time.
Yes
AWS Chiller Sequence of Operation in Cool Mode

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Start first circuit.
Yes
The first circuit to start is generally the available circuit with the least number of
starts. This circuit will go through its start sequence at this point.
Is more capacity
needed to satisfy load?
Has the stage up time
delay expired?
Yes
No
Load/unload as needed to
satisfy load.
No
The first circuit will be loaded and unloaded as needed in an attempt to satisfy the
load by controlling LWT to the Active Setpoint.
A minimum time must pass between the starting of circuits. The time remaining
can be viewed on the HMI if the minimum password level is active.
If a single circuit is not enough to satisfy the load, additional circuits will need to be
started. An additional circuit will be started when all running compressors are
loaded to a specific capacity and the LWT is higher than the Active Setpoint plus
the Stage Up Delta T.
Start next circuit.
Yes The second circuit will go through its start sequence at this point.
Note that a third circuit can be started if available. The two preceding conditions
must again be satisfied after starting the second circuit before starting the third
circuit.
Load/unload as needed to
satisfy load.
Can less circuits handle
the load?
No As the load drops off, the circuits will unload accordingly. If the LWT drops below
the Active Setpoint minus the Stage Down Delta T, one circuit will shut off. If all
running circuits are unloaded below a minimum value, this can also result in one
circuit shutting off.
A minimum time must pass between the shutting down of circuits. The time
remaining can be viewed on the HMI if the minimum password level is active.
All running circuits will now be loaded/unloaded as needed to satisfy the load.
When possible, they will load balance so that running circuits are providing nearly
equal capacity.
Yes
Shut down one circuit. The next circuit to shut off is generally the one with the most run hours.
* The points highlighted are considered only in 2 or 3 circuits units
*
*
*
*
*

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Figure 6, Circuit Sequence of Operation
Is circuit commanded to
start?
Is circuit commanded to
shut down?
Pumpdown circuit
Yes
Yes
No
Unit power up
Circuit is in Off state
No
Run circuit When the circuit begins to run, the compressor will be started and the EXV, fans,
and other devices will be controlled as needed. The normal circuit status at this
time will be Run.
When the circuit is commanded to shut down, a normal shut down of the circuit will
be performed. The circuit status during this time will be Run:Pumpdown. After
the shut down is completed, the circuit status will normally be Off:Cycle Timer
initially.
When the circuit is in the Off state the EXV is closed, compressor is off, and all fans
are off.
Is circuit is enabled to
start?
Yes
No The circuit must be enabled before it can run. It may be disabled for several
reasons. When the circuit switch is off, the status will be Off:Circuit Switch.
If the BAS has disabled the circuit, the status will be Off:BAS Disable. If the circuit
has an active stop alarm then the status will be Off:Cir Alarm. If the circuit has
been disabled via the circuit mode set point, the status will be Off:Cir Mode
Disable.
Is compressor oil sump
ready?
Yes
No
If the compressor is not ready due to refrigerant in the oil, the circuit cannot start.
The circuit status will be Off:Refr In Oil.
Circuit is ready to start If the compressor is ready to start when needed, the circuit status will be
Off:Ready.
Are compressor cycle
timers active?
No
Yes
A minimum time must pass between the previous start and stop of a compressor
and the next start. If this time has not passed, a cycle timer will be active and the
circuit status will be Off:Cycle Timer.
AWS Sequence of Operation - Circuits

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6 CONTROLLER OPERATION
6.1 MicroTech Inputs/Outputs
The chiller may be equipped with one up to three compressors.
6.1.1 Analog Inputs
#
Description
Signal Source
Expected Range
AI1
Evaporator Entering Water Temp
NTC Thermister (10K@25°C)
-50°C –120°C
AI2
Evaporator Leaving Water Temp
NTC Thermister (10K@25°C)
-50°C –120°C
AI3
Condenser Entering Water Temp
NTC Thermister (10K@25°C)
-50°C –120°C
X1
Condenser Leaving Water Temp
NTC Thermister (10K@25°C)
-50°C –120°C
X4
LWT Reset
4-20 mA Current
1 to 23 mA
X7
Demand Limit
4-20 mA Current
1 to 23 mA
X8
Unit Current
4-20 mA Current
1 to 23 mA
6.1.2 Analog Outputs
#
Description
Output Signal
Range
X5
Condenser Pump VFD
0-10VDC
0 to 100% (1000 steps resolution)
X6
Condenser Bypass Valve
0-10VDC
0 to 100% (1000 steps resolution)
6.1.3 Digital Inputs
#
Description
Signal Off
Signal On
DI1
Unit PVM
Fault
No Fault
DI2
Evaporator Flow Switch
No Flow
Flow
DI3
Double Set Point/ Mode Switch
Cool mode
Ice mode
DI4
External Alarm
Remote off
Remote on
DI5
Unit Switch
Unit off
Unit on
DI6
Emergency Stop
Unit off/rapid stop
Unit on
X2
Current Limit Enable
Disabled
Enabled
X3
Condenser Flow Switch
No Flow
Flow
6.1.4 Digital Outputs
#
Description
Output OFF
Output ON
DO1
Evaporator Water Pump #1
Pump Off
Pump On
DO2
Unit Alarm
Alarm not Active
Alarm Active (Flashing=
circuit alarm)
DO3
Cooling Tower Out 1
Fan Off
Fan On
DO4
Cooling Tower Out 2
Fan Off
Fan On
DO5
Cooling Tower Out 3
Fan Off
Fan On
DO6
Cooling Tower Out 4
Fan Off
Fan On
DO7
DO8
Evaporator Water Pump #2
Pump Off
Pump On
DO9
Condenser Water Pump
Pump Off
Pump On
6.2 Extension I/O Compressor #1 to #3
6.2.1 Analog Inputs
#
Description
Signal Source
Expected Range
X1
Discharge Temperature
NTC Thermister (10K@25°C)
-50°C –120°C
X2
Evaporator Pressure
Ratiometric (0,5-4,5 Vdc)
0 to 5 Vdc
X3
Oil Pressure
Ratiometric (0,5-4,5 Vdc)
0 to 5 Vdc
X4
Condenser Pressure
Ratiometric (0,5-4,5 Vdc)
0 to 5 Vdc

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X7
Motor Protection
PTC Thermistor
n/a
6.2.2 Analog Outputs
#
Description
Output Signal
Range
Not Needed
6.2.3 Digital Inputs
#
Description
Signal Off
Signal On
X6
Starter Fault
Fault
No fault
X8
Circuit Switch
Circuit Off
Circuit On
DI1
High Pressure Switch
Fault
No fault
6.2.4 Digital Outputs
#
Description
Output Off
Output On
DO1
Start Compressor
Compressor Off
Compressor On
DO2
Circuit Alarm
Circuit Alarm Off
Circuit Alarm On
DO3
Load #2 Circuit
Load 2 Circuit Off
Load 2 Circuit On
DO4
Unload #2 Circuit / Liquid Injection
Unload 2 Circuit Off /
Liquid Injection Off
Unload 2 Circuit On /
Liquid Injection On
DO5
Load #1 Circuit
Load 1 Circuit Off
Load 1 Circuit On
DO6
Unload #1 Circuit
Unload 1 Circuit Off
Unload 1 Circuit On
X5
Turbo Slide
Turbo Slide Off
Turbo Slide On
6.3 I/O EXV Circuit #1 to #3
6.3.1 Analog Inputs
#
Description
Signal Source
Expected Range
X1
Evaporator Leaving Water Temp (*)
NTC Thermister 10K@25°C)
-50°C –120°C
X2
Suction Temperature
NTC Thermister 10K@25°C)
-50°C –120°C
X3
6.3.2 Analog Outputs
#
Description
Output Signal
Range
Not Needed
6.3.3 Digital Inputs
#
Description
Signal Off
Signal On
DI1
Evaporator Flow Switch (Circuit)
No Flow
Flow
6.3.4 Digital Outputs
#
Description
Output Off
Output On
DO1
Liquid Line Solenoid Valve
Liquid Line Solenoid Valve Off
Liquid Line Solenoid Valve
On
6.3.5 Stepper Motor Output
#
Description
M1+
EXV Stepper Coil 1
M1-
M2+
EXV Stepper Coil 2
M2-

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6.4 Extension I/O Fan Module Circuit #2
6.4.1 Digital Outputs
#
Description
Signal source
Output On
DO1
Circuit #2 Fan Step #1 Fan Off Fan On
Fan Off
Fan On
DO2
Circuit #2 Fan Step #2 Fan Off Fan On
Fan Off
Fan On
DO3
Circuit #2 Fan Step #3 Fan Off Fan On
Fan Off
Fan On
DO4
Circuit #2 Fan Step #4 Fan Off Fan On
Fan Off
Fan On
6.5 Extension I/O Fan Module Circuit #3
6.5.1 Digital Outputs
#
Description
Output Off
Output On
DO1
Circuit #3 Fan Step #1 Fan Off Fan On
Fan Off
Fan On
DO2
Circuit #3 Fan Step #2 Fan Off Fan On
Fan Off
Fan On
DO3
Circuit #3 Fan Step #3 Fan Off Fan On
Fan Off
Fan On
DO4
Circuit #3 Fan Step #4 Fan Off Fan On
Fan Off
Fan On
6.6 Extension I/O Unit Heat Pump (Old Version)
6.6.1 Digital Inputs
#
Description
Signal Off
Signal On
DI1
Cool Heat Switch
Cooling Mode
Heating Mode
DI2
Leak Detector
No Leak detected
Leak detected
6.7 Extension I/O Unit Heat Pump (New Version)
6.7.1 Digital Outputs
#
Description
Output Off
Output On
DO1
Power Request (Marine option)
DO2
DO3
DO4
6.7.2 Analog Inputs
#
Description
Signal Source
Expected Range
AI1
Common Condenser Water Temperature
NTC Thermister 10K@25°C)
-50°C –120°C
6.7.3 Digital Inputs
#
Description
Signal Off
Signal On
AI 2
Mode Switch
Cooling Mode
Heating Mode
AI 3
Leak Detector
No Leak detected
Leak detected
AI 4
Power Available (Marine option)
6.8 Setpoints
6.8.1 Auto Adjusted Ranges
Some settings have different ranges of adjustment based on the refrigerant type and operating mode.
Please refer to the product catalog for further information.

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7 UNIT FUNCTIONS
7.1 Calculations
7.1.1 LWT Slope
LWT slope is calculated such that the slope represents the change in LWT over a time frame of one minute with at least
five samples per minute for both evaporator and condenser.
7.1.2 Pulldown Rate
The slope value calculated above will be a negative value as the water temperature is dropping. For use in some control
functions, the negative slope is converted to a positive value by multiplying by –1.
7.2 Unit Model
Theunit model can be selected between the fouravailable for this application. Depending on themodeltemperature ranges
and refrigerant type are selected automatically.
7.3 Unit Enable
Enabling and disabling the chiller is accomplished using set points and inputs to the chiller. The unit switch, remote switch
input, and Unit Enable Set Point all are required to be on for the unit to be enabled when the control source is set to local.
The same is true if the control source is set to network, with the additional requirement that the BAS request must be on.
Unit is enabled according to the following table.
NOTE: An x indicates that the value is ignored.
Unit Switch
Control Source
Set Point
Remote Switch
Input
Unit Enable Set
Point
BAS Request
Unit Enable
Off
x
x
x
x
Off
x
x
x
Off
x
Off
x
x
Off
x
x
Off
On
Local
On
On
x
On
x
Network
x
x
Off
Off
On
Network
On
On
On
On
All of the methods for disabling the chiller, discussed in this section, will cause a normal shutdown (pumpdown) of any
running circuits.
When the controller is powered up, the Unit Enable Set Point will be initialized to ‘off’ if the Unit Status After Power Fai lure
Set Point is set to ‘off’.
7.4 Unit Mode Selection
The operating mode of the unit is determined by setpoints and inputs to the chiller. The Available Modes Set Point
determines what modes of operation can be used. This setpoint also determines whether the unit is configured for glycol
use. The Control Source Set Point determines where a command to change modes will come from. A digital input switches
between cool mode and ice mode if they are available and the control source is set to local. The BAS mode request
switches between cool mode and ice mode if they are both available and the control source is set to network.

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The Available Modes Set Point must only be changed when the unit switch is off. This is to avoid changing modes of
operation inadvertently while the chiller is running.
Unit Mode is set according to the following table.
NOTE: An “x” indicates that the value is ignored.
Control Source
Set Point
Mode
Input
HP Switch
BAS Request
Available Modes Set
Point
Unit Mode
x
x
x
x
Cool
Cool
x
x
x
x
Cool w/Glycol
Cool
Local
Off
x
x
Cool/Ice w/Glycol
Cool
Local
On
x
x
Cool/Ice w/Glycol
Ice
Network
x
x
Cool
Cool/Ice w/Glycol
Cool
Network
x
x
Ice
Cool/Ice w/Glycol
Ice
x
x
x
x
Ice w/Glycol
Ice
Local
x
Off
x
Cool/Heat
Cool
Local
x
On
x
Cool/Heat
Heat
Network
x
x
Cool
Cool/Heat
Cool
Network
x
x
Heat
Cool/Heat
Heat
Local
Off
Off
x
Cool/Ice w/Glycol/ Heat
Cool
Local
On
Off
x
Cool/Ice w/Glycol/ Heat
Ice
Local
x
On
x
Cool w/Glycol/Heat
Cool
Local
x
On
x
Cool w/Glycol/Heat
Heat
Network
x
x
Cool
Cool/Ice w/Glycol/ Heat
Cool
Network
x
x
Ice
Cool/Ice w/Glycol/ Heat
Ice
Network
x
x
Heat
Cool/Ice w/Glycol/ Heat
Heat
x
x
x
Test
Test
7.4.1 Glycol Configuration
If the Available Modes Set Point is set to an option w/Glycol, then glycol operation is enabled for the unit. Glycol operation
must be disabled only when the Available Modes Set Point is set to Cool.
7.5 Unit Control States
The unit will always be in one of three states:
•Off –Unit is not enabled to run.
•Auto –Unit is enabled to run.
•Pumpdown –Unit is doing a normal shutdown.
The unit will be in the Off state if any of the following are true:
•A manual reset unit alarm is active
•All circuits are unavailable to start (cannot start even after any cycle timers have expired)
•The unit mode is ice, all circuits are off, and the ice mode delay is active
The unit will be in the Auto state if any of the following are true:
•Unit enabled based on settings and switches
•If unit mode is ice, the ice timer has expired
•No manual reset unit alarms are active
•At least one circuit is enabled and available to start
The unit will be in Pumpdown until all running compressors finish pumping down if any of the following are true:
•Unit is disabled via settings and/or inputs in section 7.2

19/77
Operation Manual
D–EOMWC00A07-16_02EN
7.6 Unit Status
The displayed unit status is determined by the conditions in the following table:
Enum
Status
Conditions
0
Auto
Unit State = Auto
1
Off:Ice Mode Timer
Unit State = Off, Unit Mode = Ice, and Ice Delay = Active
2
-
-
3
Off:All Cir Disabled
Unit State = Off and all compressors unavailable
4
Off:Unit Alarm
Unit State = Off and Unit Alarm active
5
Off:Keypad Disable
Unit State = Off and Unit Enable Set Point = Disable
6
Off:Remote Switch
Unit State = Off and Remote Switch is open
7
Off:BAS Disable
Unit State = Off, Control Source = Network, and BAS Enable = false
8
Off:Unit Switch
Unit State = Off and Unit Switch = Disable
9
Off:Test Mode
Unit State = Off and Unit Mode = Test
10
Auto:Noise Reduction
Unit State = Auto and Noise Reduction is active
11
Auto:Wait for load
Unit State = Auto, no circuits running, and LWT is less than the active
set point + startup delta
12
Auto:Evap Recirc
Unit State = Auto and Evaporator State = Start
13
Auto:Wait for flow
Unit State = Auto, Evaporator State = Start, and Flow Switch is open
14
Auto:Pumpdown
Unit State = Pumpdown
15
Auto:Max Pulldown
Unit State = Auto, max pulldown rate has been met or exceeded
16
Auto:Unit Cap Limit
Unit State = Auto, unit capacity limit has been met or exceeded
17
Auto:Current Limit
Unit State = Auto, unit current limit has been met or exceeded
18
Off:Config Changed, Reboot
Unit State = Off and Unit Enable Set Point = Disable
19
Off:Set Mfg Location
Unit State = Off and Unit Enable Set Point = Disable
7.7 Ice Mode Start Delay
An adjustable start-to-start ice delay timer will limit the frequency with which the chiller may start in Ice mode. The timer
starts when the first compressor starts while the unit is in ice mode. While this timer is active, the chiller cannot restart in
Ice mode. The time delay is user adjustable.
The ice delay timer may be manually cleared to force a restart in ice mode. A set point specifically for clearing the ice mode
delay is available. In addition, cycling the power to the controller will clear the ice delay timer.
7.8 Evaporator Pump Control
Three evaporator pump control states for control of the evaporator pumps:
•Off - No pump on.
•Start –Pump is on, water loop is being recirculated.
•Run –Pump is on, water loop has been recirculated.
The control state is Off when all of the following are true:
•Unit state is Off
•LWT is higher than the Evap Freeze set point or LWT sensor fault is active
•EWT is higher than the Evap Freeze set point or EWT sensor fault is active
The control state is Start when any of the following are true:
•The unit state is auto
•LWT is less than the Evap Freeze set point minus 0.6 °C and LWT sensor fault isn’t active
•EWT is less than the Evap Freeze set point minus 0.6 °C and EWT sensor fault isn’t active
The control state is Run when the flow switch input has been closed for a time greater than the Evaporator Recirculate set
point.

D–EOMWC00A07-16_02EN
Operation Manual
20/77
7.8.1 Pump Selection
The pump output used is determined by the Evap Pump Control set point. This setting allows the following configurations:
•#1 only –Pump 1 will always be used
•#2 only –Pump 2 will always be used
•Auto –The primary pump is the one with the least run hours, the other is used as a backup
•#1 Primary –Pump 1 is used normally, with pump 2 as a backup
•#2 Primary –Pump 2 is used normally, with pump 1 as a backup
Primary/Standby Pump Staging
The pump designated as primary will start first. If the evaporator state is start for a time greater than the recirculate timeout
set point and there is no flow, then the primary pump will shut off and the standby pump will start. When the evaporator is
in the run state, if flow is lost for more than half of the flow proof set point value, the primary pump will shut off and the
standby pump will start. Once the standby pump is started, the flow loss alarm logic will apply if flow cannot be established
in the evaporator start state, or if flow is lost in the evaporator run state.
Auto Control
If auto pump control is selected, the primary/standby logic above is still used. When the evaporator is not in the run state,
the run hours of the pumps will be compared. The pump with the least hours will be designated as the primary at this time.
7.9 Condenser Pump Control
There are three condenser pump control states for control of the condenser pump:
•Off
•Start –Pump is on, water loop is being recirculated
•Run –Pump is on, water loop has been recirculated
The control state is Off when any of the following are true:
•Unit state is Off
•LWT is higher of Evap Freeze set point or LWT sensor fault is active
•EWT is higher of Evap Freeze set point or EWT sensor fault is active
The control state is Start when any of the following are true:
•The unit state is auto
•LWT is lower than (Evap Freeze set point - 0.6 °C) and LWT sensor fault is not active or EWT is lower than
(Evap Freeze set point –0.6 °C) and EWT sensor fault is not active.
The control state is Run when the flow switch input has been closed for a time greater than the loop Recirculate set point.
7.10 Condensation Control
Three condensation control modes are available:
•Cond In –the condensation control measure is the condenser entering water temperature
•Cond Out - the condensation control measure is the condenser leaving water temperature
•Pressure - the condensation control measure is the gas pressure referred to condenser saturated temperature
The Condenser control mode is determined by the Condensation Control Value set point.
Within these control modes, the application manages the outputs for the control of condensation devices:
•n.4 on/off signals, always available
•n.1 modulating 0-10V signal, whose availability is determined by the Condensation Analog Output type set
point.