Product manual

KPMWC00905-10EN - page 23/24
• Liquid line temperature
• Chilled water setpoint
• Compressor and unit state and input and output digital and analog values
4. A fault history shall be displayed using an easy to decipher, color coded set of messages that are date and time
stamped. The alarm history shall be downloadable from the unit's USB port. An operating and maintenance
manual specific for the unit shall be viewable on the screen.
5. All setpoints shall be viewable and changeable (multi-level password protected) on the touch screen and include
setpoint description and range of set values.
6. Automatic corrective action to reduce unnecessary cycling shall be accomplished through preemptive control of
low evaporator or high discharge pressure conditions to keep the unit operating through abnormal transient
conditions.
7. Optionally, the factory mounted controller(s) shall support operation on a BACnet®, Modbus® or LONWORKS®
network via one of the data link / physical layers listed below as specified by the successful Building Automation
System (BAS) supplier.
• Modbus
• BACnet MS/TP master (Clause 9)
• BACnet IP
• BACnet ISO 8802-3, (Ethernet)
• LonTalk® FTT-10A. The unit controller shall be LONMARK ® certified.
8. The information communicated between the BAS and the factory mounted unit controllers shall include the
reading and writing of data to allow unit monitoring, control and alarm notification as specified in the unit
sequence of operation and the unit points list.
9. For chillers communicating over a LONMARK network, the corresponding LONMARK eXternal Interface File (XIF)
shall be provided with the chiller submittal data.
10. All communication from the chiller unit controller as specified in the points list shall be via standard BACnet
objects. Proprietary BACnet objects shall not be allowed. BACnet communications shall conform to the BACnet
protocol. A BACnet Protocol Implementation Conformance Statement (PICS) shall be provided along with the unit
submittal.
9 Field power connection, control interlock terminals, and unit control system should be centrally located in an
electric panel (IP 54). Power and starting controls should be separate from safety and operating controls in
different compartments of the same panel.
9 Operating and safety controls should include energy saving control; emergency stop switch; high and low
pressure cut-out switch (for each refrigerant circuit); anti-freeze thermostat; cut-out switch for each compressor.
9 All of the information regarding the unit will be reported on a display and with the internal built-in calendar and
clock that will switch the unit ON/OFF during day time all year long.
9 The following features and functions shall be included:
- leaving water temperature reset
by controlling the water temperature Δt, by a remote 4-20mA DC signal
or by controlling the external ambient temperature;
- soft load function
to prevent the system from operating at full load during the chilled fluid pulldown period;
- password protection
of critical parameters of control;
- start-to-start and stop-to-start timers
to provide minimum compressor off-time with maximum motor
protection;
- communication capability
with a PC or remote monitoring;
- discharge pressure control
through intelligent cycling of condenser fans;
- lead-lag selection
by manual or automatically by circuit run hours;
- double set point
for unit version;
- scheduling
via internal time clock to allow programming of a yearly start-stop schedule accommodating
weekends and holidays.
Optional High Level Communications Interface
Chiller must be able to communicate to BMS (Building Management System) based on the most common protocols as:
• ModbusRTU
• LonWorks, now also based on the international 8040 Standard Chiller Profile and LonMark Technology
• BacNet BTP certifief over IP and MS/TP (class 4) (Native)
• Ethernet TCP/IP.