Quantech QTC3040T, Installation Operation & Maintenance, Page: 17 / 190

17
QUANTECH
FORM QTC3-NM1
ISSUE DATE 08/03/2022
SECTION 2 – PRODUCT DESCRIPTION
2
Control Center
All controls are contained in a NEMA 3R/12 cabinet
with hinged outer door and includes a Liquid Crystal
Display with Light Emitting Diode backlighting for
outdoor viewing:
• Two display lines
• Twenty characters per line
Display/Print Keys
• Color coded 12-button non-tactile keypad with sec-
tions for display and print of typical information:
• Chilled liquid temperatures
• Ambient temperature
• System pressures (each circuit)
• Operating hours and starts (each compressor)
• Print calls up to the liquid crystal display
• Operating data for the systems
• History of fault shutdown data for up to the last
six fault shutdown conditions.
• An RS-232 port, in conjunction with this press-to-
print button, is provided to permit the capability
of hard copy print-outs via a separate printer (by
others)
Entry Keys
This section is used to enter setpoints or modify system
values.
Setpoints Keys
Updating can be performed to:
• Chilled liquid temperature setpoint and range
• Remote reset temperature range
• Set daily schedule/holiday for start/stop
• Manual override for servicing
• Low and high ambient cutouts
• Number of compressors
• Low liquid temperature cutout
• Low suction pressure cutout
• High discharge pressure cutout
• Anti-recycle timer (compressor start cycle time)
• Anti-coincident timer (delay compressor starts)
Unit Keys
This section is used to:
• Set time
• Set unit options
Oper Data Key
The microprocessor control center is capable of dis-
playing the following:
• Return and leaving liquid temperature
• Low leaving liquid temperature cutout setting
• Low ambient temperature cutout setting
• Outdoor air temperature
• English or Metric data
• Suction pressure cutout setting
• Each system suction pressure
• Discharge pressure (optional)
• Liquid Temperature Reset via a Johnson Controls
ISN DDC or Building Automation System (by
others) via a 4 mA to 20 mA or 0 VDC to10 VDC
input
• Anti-recycle timer status for each system
• Anti-coincident system start timer condition
• Compressor run status
• No cooling load condition
• Day, date and time
• Daily start/stop times
• Holiday status
• Automatic or manual system lead/lag control
•
Lead system definition
• Compressor starts and operating hours
• (each compressor)
• Status of hot gas valves, evaporator heater and fan
operation
• Run permissive status
• Number of compressors running
• Liquid solenoid valve status
• Load and unload timer status
• Water pump status
Provisions are included for: pumpdown at shutdown;
optional remote chilled water temperature reset and
two steps of demand load limiting from an external
building automation system. Unit alarm contacts are
standard.
The operating program is stored in non-volatile-memo-
ry, battery backed RAM to eliminate chiller failure due
to AC powered failure/battery discharge. Programmed
setpoints are retained in lithium battery-backed RTC
memory for 5 years minimum.