IM 743-7 • MICROTECH II CHILLER UNIT CONTROLLER 4
www.DaikinApplied.com
Introduction
Hazardous Information Messages
Recognize Safety Symbols, Words and Labels
The following symbols and labels are used throughout this
manual to indicate immediate or potential hazards. It is the
owner and installer’s responsibility to read and comply with
all safety information and instructions accompanying these
symbols. Failure to heed safety information increases the
risk of property damage and/or product damage, serious
personal injury or death. Improper installation, operation and
maintenance can void the warranty.
CAUTION
Cautions indicate potentially hazardous situations, which can result in
personal injury or equipment damage if not avoided.
Static sensitive components. Can cause equipment damage.
Discharge any static electrical charge by touching the bare metal inside the
control panel before performing any service work. Never unplug cables,
circuit board terminal blocks, or power plugs while power is applied to the
panel
WARNING
Warnings indicate potentially hazardous situations, which can result in
property damage, severe personal injury, or death if not avoided.
DANGER
Dangers indicate a hazardous situation which will result in death or
serious injury if not avoided. Electric shock hazard. Can cause personal
injury or equipment damage. This equipment must be properly grounded.
Connections and service to the MicroTech II Unit Controller must be
performed only by personnel knowledgeable in the operation of the
equipment being controlled.
NOTICE
This equipment generates, uses and can radiate radio frequency energy
and, if not installed and used in accordance with this instruction manual,
may cause interference to radio communications. It has been tested and
found to comply with the limits for a Class A digital device, pursuant to
part 15 of the FCC rules. These limits are designed to provide reasonable
protection against harmful interference when the equipment is operated in a
commercial environment. Operation of this equipment in a residential area
is likely to cause harmful interference in which case the user will be required
to correct the interference at his or her own expense. Daikin disclaims any
liability resulting from any interference or for the correction thereof.
The Modbus communication module connects the
MicroTech II chiller unit controller to a building automation
system (BAS). This interface enables the exchange of Modbus
data points between the unit controller and the network.
The Modbus communication module, together with the unit
controller, support the Modbus RTU standard protocol.
Features
• Integration into a building automation and control system
once inserted into the unit controller
• LEDs that indicate communication status and network
activity
• Network addressing and baud rate set directly from the
unit controller
• Modbus application pre-installed and ready for custom
configuration
Specifications
The following section provides a summary of technical data
and conformance to agency listings.
General
Dimensions
2
3/8
” x 1
3/16
” (60 x 30 mm)
Operating
Temperature
14 - 140°F (-10 - 60°C)
Humidity
90% RH
Storage and Transportation
Temperature
-4 - 158°F (-20 - 70°C)
Humidity
90% RH
Electrical
Power
8-38 VDC (+5% / –5%) bus connector, max. 1W
Network cable
RS-485 (EIA-485)
two-wire twisted pair, shielded AWG 20-22, max
3281 ft 888(1000 m)
Bus connection/
Transceiver
Opto-isolated
A-, B+, GND (2 wires)
Bus termination
120
Ω
end of line resistor for units at start or end
of trunk
Data transmission
(baud rate)
1200, 2400, 4800, 9600, 19200, (default) bps
Additional Components
Modbus network
connector
RS-485 connection plug
Agency Listings - Unit Controller
US
UL 873
Canada
CSA C22.2 No. 24-93
