Bus Termination; Transmission Specifications; Software Interface To Unit Controller - Daikin MicroTech III Installation And Maintenance Manual

Bus Termination

Bus termination resistors are used for properly terminating
a network based on twisted pair cabling with attention to
impedance.
NOTE: Refer to Echelon L
User's Guide for details regarding acceptable
configurations, cabling requirements,
terminations, impedance, and other requirements
(www.echelon.com).

Transmission Specifications

Component Value
Network topology Flexible Free Topology
Neuron chip processor 3150
Free Topology Transceiver
50051
(FTT-10A)
Cable types TIA Category 5 (recommended)
Maximum cable length 1476 ft (450 m) per segment (total of all lines)
Maximum node separation 820 ft (250 m)
Data transmission Two-wire, half duplex
Data transmission rate 78 kbps (baud)
Free topology: use one (1) 52.3 Ω bus terminator
at the busiest point of the network
Bus terminator
Daisy chain or standard line (dual) topology: use
two (2) 105 Ω bus terminators at the end of both
network segments
Repeaters and router are typically used when the
entire cable length in a given segment exceeds
1476 ft (450 m) in a free topology or 2953 ft
(900 m) in a line topology.
Repeaters and routers
Each trunk can have at maximum one physical
repeater. Repeaters and routers may not be used
in a ring topology. They must be placed before
the network's ring port.
www.DaikinApplied.com
W FTT-10A Transceiver
on orks

Software Interface to Unit Controller

The L W communication module software translates
on orks
the Standard Network Variable Types (SNVTs) and Standard
Network Configuration Parameter Types (SCPTs) used in
the MicroTech III chiller unit controller into the variables and
parameters used by the L
conforms to the LonMark 3.4 chiller profile. Refer to MicroTech
III Chiller Unit Controller Protocol Document, ED 15120 for
additional information (www.DaikinApplied.com).
7 IM 968-4 • MICROTECH III CHILLER UNIT CONTROLLER
I
nTroduCTIon
W network. The software
on orks