McQuay MicroTech 200 Series Operating Manual Download Page 27

OM 200MICRO

27

Demand Limit

—Allows the MicroTech to control chiller motor amperage based on a remote 4-20

mA signal supplied by a building automation system input.  The 4-20 mA signal limits the
capacity of the chiller and saves electrical demand charges.

Active Spt=

 This is a status value and cannot be changed.

Active spt

 indicates the set point that is

controlling the chiller.  If current limiting is active, the maximum allowable percent of RLA will be
displayed.  It is a diagnostic aide when compared to the 

max amp spt

 value.

Reset Signal=

 A status value indicating the reset signal 

(in milliamps)

 currently being applied.

Min Amp Spt=

 A value must be entered even if the 

demand limit

 option was not selected.  This is the

minimum amperage 

(low limit)

 of the 

demand limit

 option and 

(low limit)

 for normal chiller operation.

The chiller will not unload below this value.

Network Spt=

 This value cannot be adjusted 

(0-100%).

  It is the value supplied by the network level

1 controllers.

Max Amp Spt=

 This value has priority over demand limit and network spt.  This should be the

maximum operational amperage of the unit.  Normal set point would be 100.  This value can be used to
limit the operational amperage should abnormal conditions exist.

Soft Load=

 This value activates the soft load 

(ramp up)

 option if set to on.  Upon chiller start, soft

load takes over control when the chiller amperage is equal to the 

begin amp

 km and loads up over the

ramp time

 to the 

max amp spt.

Begin Amp Lim=

 A value must be entered if the 

soft load

 option was set to on. Select an amperage

value that allows the chiller to start and establish proper operating conditions.  This will eliminate
nuisance start up trips.

Ramp Time=

 The default ramp time is usually adequate; however the soft load time can be extended

up to 60 minutes.

Press the "NEXT MENU" key and menu 14 

(Set Time/Date)

 will be displayed.  Menu 14 has one

screen.  This menu is password protected and requires the operator password.

These values must be set in the menu to allow MicroTech to control start/stop and holiday functions.
MicroTech will not start the chiller until this menu is completed.

Menu 14, Set Time Date

Item

Screen

Line

Display

Field

Range

Extended Name

hh:mm:ss

1

00:00:00-23:59:59

Current Hour, Min, Sec

day

2

Sun-Sat

Current Day

1

1

mm-dd-yy

3

Jan-Dec, 1-31,00-99

Current Date

Press the "NEXT MENU" key and menu 15 

(Schedule)

 will be displayed.  Menu 15 has two screens.

This menu is password protected and requires the operator password.

Summary of Contents for MicroTech 200 Series

Page 1: ...Operating Manual OM 200MICRO Group Chiller Part Number 585515Y Effective April 2000 Supersedes OM125 1999 McQuay International 200 Series MicroTech Control Panel For Centrifugal Chillers...

Page 2: ...ech Status Menus 18 Control Menu Description 24 Alarm Menus Description 38 Master Slave Setup 41 Alarms 43 McQuay and MicroTech are registered trademarks of McQuay International 1998 McQuay Internatio...

Page 3: ...rge 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...

Page 4: ...ons If a fault condition develops the controller will shut the system down and activate an alarm output Important operating conditions at the time an alarm condition occurs are retained in the control...

Page 5: ...ondition occurred In addition the operating conditions that existed just prior to shutdown can be recalled to aid in isolating the cause of the problem Eight previous faults and related operating cond...

Page 6: ...tus LED s located on the model 280 controller which will indicate the microprocessor s operating condition When power is first applied to the control panel the red reset LED will illuminate for approx...

Page 7: ...will be appropriate for most common installations Step through all of the unit s setpoints by using the keypad display and adjust them as required to meet the specific job requirements Any faults app...

Page 8: ...er Water Pump 1 Off On 18 Condenser Water Pump 2 Off On 19 Spare 20 Spare 21 Spare 22 Spare 23 Spare Analog Digital Input Board ADI The ADI Board provides low voltage power for the temperature and pre...

Page 9: ...OM 200MICRO 9 of 4 20 mA Temperature and pressure readings have a resolution of 0 1 F and 0 1 psi respectively Flow readings and remote reset signals are resolved to 1...

Page 10: ...Vent Pressure 0 165 psig 0 1137 6 kPa 16 S16 Evaporator Refrigerant Pressure 0 165 psig 0 1137 6 kPa 17 S17 Condenser Refrigerant Pressure 0 165 psig 0 1137 6 kPa 18 S18 Oil Feed Gauge Pressure 0 165...

Page 11: ...analog signal that is proportional to compressor motor current Figure 7 AOX Board Analog Outputs Optional The analog outputs available at the AOX board provide a variable voltage used to control field...

Page 12: ...ardistor board monitors the motor winding temperature through the embedded Guardistor sensors If the motor temperature rises to an unsafe level the board will signal the M280 controller and the chille...

Page 13: ...can be accessed through the keypad by following the tree like structure of menus and menu items The keypad keys are divided into four groups with four or more keys in each to ease navigation through t...

Page 14: ...11 Control Mode which is the first menu of the CONTROL category Alarm Key Menus and menu items in this category provide information regarding current and previous fault conditions along with the oper...

Page 15: ...he display pressing NEXT causes and end of items message to appear in the display Previous Item Pressing PREV shifts the display to the previous group of items within a menu Note When the first item i...

Page 16: ...ries After entering the correct password the controller will allow a 5 minute time period during which the operator may make any necessary setpoint adjustments Any keypad activity will reset the timer...

Page 17: ...change the numeric value or select the next option When the correct value or option is flashing press the ENTER key to store it into memory The flashing will stop and the time and date is returned to...

Page 18: ...Field Range Extended Name AllSystemsOff Off Alarm Off Ambient Lockout Off Front Panel Sw Off Remote Contacts Off Remote Comm Off Time Schedule Off Manual Setpoint Off System Comm Start Requested Waiti...

Page 19: ...Lvg Ht Rcvy xx x F 1 Heat Recv Lvg Water Temp 2 Cond Flow xxxxgpm 2 Averaged Cond Water Flow 2 3 Delta T xx x F 1 Heat Rcvy Delta Temp Press the NEXT MENU key and Menu 3 Refrig Temps Press will be dis...

Page 20: ...g value if limiting is being enforced by the control software Pressing the switch key will toggle between this menu and Menu 13 MotorAmp Set Points This allows the operator to compare actual operating...

Page 21: ...ower valve is controlled by the chiller Screen 2 line 1 field 1 indicates the outdoor air temperature This is optional and will be valid if an out door thermistor is installed Pressing the switch key...

Page 22: ...perator to compare actual operating conditions versus set points Menu 23 is only available on the master chiller when a network exists between two 200 Series MicroTech chillers A network can be establ...

Page 23: ...Temp 2 Evap Flow xx x F 2 Recorded Evap Water Flow Feed Press xx xpsi 1 Recorded Oil Feed Pressure 4 3 Cond Flow xxxxpgm 1 Recorded Cond Water Flow 1 Wk Ending 1 Date of Previous Log Peak xxx 1 Record...

Page 24: ...al Off Selected Unit Operation Manual Off This mode causes the chiller to stop If the unit is operating it will go through a controlled shutdown and remain off If the unit is off it will remain off Au...

Page 25: ...ater temperature set point Local Spt This is the actual chilled water leaving temperature for the chiller to maintain if there is not a network Local spt is active depending upon which set point sourc...

Page 26: ...elected as a reset option If this set point is set to high it can cause the compressor to surge and damage the chiller Return Spt This value will control the MicroTech if the chw reset option was set...

Page 27: ...This value can be used to limit the operational amperage should abnormal conditions exist Soft Load This value activates the soft load ramp up option if set to on Upon chiller start soft load takes ov...

Page 28: ...for each day of the week should be entered The default value 00 00 23 59 allows the chiller to operate continuously Hol The time entered at this menu will control the chiller nun time for the holiday...

Page 29: ...t to Start Delay Timer 2 Evap Recirc 15Sec 1 15 Sec 5 Min Chilled Water Recirculation Timer 1 3 Stop Start 3Min 1 3 20 Min Stop to Start Delay Timer Start Start This value determines the minimum time...

Page 30: ...econd pump number 2 will not be started if number 1 fails Pmp 2 Only The pump designated as number 2 will be started and the second pump number 1 will not be started if number 2 fails Auto Lead The Mi...

Page 31: ...Stageup Time This value will delay the MicroTech from starting the staging control This can be used to provide specific system control requirements Stagedn Time This value will delay the MicroTech fr...

Page 32: ...egration Time Max Change 4 1 1 20 Max Allowable Valve Pos Change 2 3 PA Time 15Min 2 1 0 60 Min Proj Ahead Calculation Window Min Start Pos 0 1 0 100 Min Valve Position at Startup 1 Max Start Position...

Page 33: ...an Changing these values could cause compressor damage The menu can be monitored and set points compared to actual operating conditions Menu 22 Alarm Set Points Item Screen Line Display Field Range Ex...

Page 34: ...ad unit The chiller with the most run time will turn off first when only one chiller is required to meet load conditions Slave Lead The slave chiller will start first each time and the master chiller...

Page 35: ...d protected and requires the service password Menu 25 Service Testing Item Screen Line Display Field Range Extended Name Output 0 Off 1 Off On Manual Output Control 1 Output 3 Off 2 Off On Manual Outp...

Page 36: ...pe WSC063 2 WSC126 Chiller Model Number L1 TTY Master L1 TTY TTY L2 Master Slave L2 TTY Slave Config L2 TTY Slave 1 L3 TTY Slave Unit Controller Configuration Chiller 2 Chiller Only 2 Templifier Chill...

Page 37: ...orator flow sensor The MicroTech scales the value linearly between 4 and 20 milliamp input or 0 to 10VDC input Ambient Lockout This value determines according to the outside air temperature the point...

Page 38: ...ooling at Alarm Dsch Suprht xxx x F 1 Discharge Superheat at Alarm 2 Sump Temp xxx x F 2 Oil Sump Temp at Alarm Suct Suprhtxxx x F 1 Suction Superheat at Alarm 3 3 Feed Tempxxx x F 2 Oil Feed Temp at...

Page 39: ...depending on this setting Problems This value will define how problems will report open close or how fast slow the reporting will occur Only one can be selected If fast slow is selected the alarm cont...

Page 40: ...40 OM 200MICRO Menu 37 Message Board Item Screen Line Display Field Range Extended Name 1 1 No Message A Message can be Posted via a Connected Computer...

Page 41: ...Low Temperature No 2 No Yes Ice Operation Master Master Slave Slave 1 Slave Network Configuration 1 Evap Gpm Sensor No 2 Yes No Evaporator Flow Transmitter None Local OAT Sensor None 1 Remote Locatio...

Page 42: ...the least run time will start as the lead unit The chiller with the most run time will turn off first when only one chiller is required to meet load conditions Slave Lead The slave chiller will start...

Page 43: ...ride normal chiller operation in order to keep the unit on line PROBLEM CONDITION DISPLAY ACTION CLEAR Entering Evaporator Water Temperature Sensor Fail Problem Sensor is shorted or open and Leaving W...

Page 44: ...pPumpsOff and Evaporator Water Flow switch digital input in No Flow position for more then 3 seconds adjustable and Evaporator pump 1 is present and Evaporator pump 1 has not yet failed Evap Pump 2 Fa...

Page 45: ...ch Hi Pres Switch High Motor Temperature Motor High Temperature digital input in Alarm position High Motor Temp High Suction Superheat Suction Superheat temperature Set Point 50 F Hi Suction Superht N...

Page 46: ...Post Office Box 2510 Staunton Virginia 24402 2510 800 432 1342 www mcquay com...

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