Danfoss VLT HVAC Drive Metasys N2, Manual

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2.1.1. Abbreviations and Definitions
Abbreviations and definitions
ACK Acknowledge
ADF Internal Floating Points
ADI Internal Integers
AI Analog Inputs
AO Analog Outputs
BI Binary Inputs
BO Binary Outputs
COS Change Of State
HPFB High Performance Field Bus
JCI Johnson Controls Inc. developers of the METASYS N2 protocol
N2 METASYS N2
N2 master A N2 master is either a PC with JCI software or a dedicated JCI controller
NAK Not acknowledged
NPA N2 Point Address (Each N2 Point Type has a address range from 0 to 255)
NPT N2 Point Type
PAR Parameter Number
2.1.2. Network Connection
Connect signal wires to terminal 68 (N+) and terminal 69 (N-) on main control board of the drive.
If shielded cabling is used, connect one end of the shield to terminal 61. This terminal is connected
to ground via an internal RC link. It is highly recommended to use twisted-pair cables to reduce
the differential mode interference between the conductors
Torque Specifications: 4.5 in.lb. (0.5 Nm)
Control wire: 18 - 24 AWG, shielded, twisted pair
2.1.3. Hardware Set-up
RS 485 Bus Connection:
One or more frequency converters can be connected to a control (or master) using the RS485
standardized interface. Terminal 68 is connected to the P signal (TX+, RX+), while terminal 69 is
connected to the N signal (TX-,RX-). If more than one frequency converter is connected to a
master, use parallel connections.
VLT ® HVAC Drive Metasys N2 2. Instructions
MG.11.G1.02 - VLT ® is a registered Danfoss trademark
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