Daikin WMC, Инструкция по установке, эксплуатации и обслуживанию, Страница: 60 / 68

o
peraTIon
IOM 1210-1 • MAGNITUDE
®
MODEL WMC CHILLERS 58 www.DaikinApplied.com
Building Automation
Systems (BAS)
All MicroTech
®
II controllers with Open Choices
™
are
capable of BAS communications, providing easy integration
and comprehensive monitoring, control, and two-way data
exchange with open standard protocols such as LonTalk
®
,
Modbus
®
or BACnet
®
.
Daikin Applied unit controllers strictly conform to the
interoperability guidelines of the LonMark
®
Interoperability
Association and BACnet ® International. They have received
LonMark
®
certification with optional L
on
W
orks
®
communication
module.
Protocol Options
The following protocol options are available:
• BACnet
®
MS/TP
• L
on
W
orks
®
• BACnet ® IP
• Modbus
®
RTU
• BACnet
®
Ethernet
The BAS communication module can be ordered with the
chiller and factory-mounted or can be field-mounted at any time
after the chiller unit is installed. Connection to the chiller for all
BAS protocols will be at the unit controller. An interface card,
depending on the protocol being used, will have been factory
installed in the unit controller if so ordered, or it can be field
installed.
If an interface module was ordered, the appropriate BAS
interface installation manual was shipped with the unit. If
necessary, contact your local Daikin Applied sales office for a
replacement manual or obtain one from www.DaikinApplied.
com . These documents can be easily found on the website
using the “Search Literature” feature.
Use with On-Site Generators
Magnitude ® Model WMC chillers have their total tonnage
divided between the number of compressors on the chiller.
The compressor(s) are operated with variable frequency
drives and if the unit has two compressors, the compressors
start sequentially. These features make Magnitude ® chillers
especially appropriate for use in applications where they may
be required to run with on-site electrical generators. This is
particularly true when the generators are used for temporary
power when the utility power is lost.
Generator Sizing
Gas and diesel generators are sensitive to the compressor’s
locked-rotor characteristics when the chillers start up. Use the
electrical data supplied with the performance output sheet,
obtained from the Daikin Applied sales office, for generator
sizing purposes. The chiller data sheet will show the RLA,
which is for each compressor. Refer to Electrical Data to
determine the LRA, which is based on the RLA. It is important
to size the generator to handle the LRA at startup.
WARNING
Generator must be sized by an electrical engineer familiar
with generator applications.
Transfer Back to Grid Power
Proper transfer from stand-by generator power back to grid
power is essential to avoid compressor damage.
WARNING
Stop the chiller before transferring supply power from the
generator back to the utility power grid. Transferring power
while the chiller is running can cause severe compressor
damage.
The necessary procedure for reconnecting power from the
generator back to the utility grid is as follows:
1. Set the generator to always run five minutes longer than
the unit start-to-start timer, which can be set from two to
sixty minutes. The actual setting can be viewed on the
OITS on the TIMERS Setpoint Screen (see Figure 28 on
page 28 ).
2. Configure the transfer switch provided with the
generator to automatically shut down the chiller before
transfer is made. The automatic shut-off function can
be accomplished through a BAS interface or with the
“remote on/off” wiring connection shown in "Figure 13:
Controller Box Wiring" on page 14 .
It is not necessary to shutdown the chiller if pumps are not
directly controlled by the chiller. Doing so, however, provides a
more coordinated restart.
A start signal can be given anytime after the stop signal since
the three-minute start-to-start timer will be in effect.