Danfoss VLT HVAC Drive Metasys N2 User manual

Contents
Introduction 3
About this Manual 3
References 3
Abbreviations and Definitions 5
Network Connection 5
Hardware Set-up 5
VLT Parameters 7
Analog Inputs (AI) 23
Binary Inputs (BI) 24
Analog Outputs (AO) 28
Binary Outputs (BO) 29
Internal Floating Point (ADF) 30
Internal Integers (ADI) 33
Index
35
VLT
®
HVAC Drive Metasys N2 Contents
MG.11.G1.02 - VLT®is a registered Danfoss trademark 1

1. Overview VLT
®
HVAC Drive Metasys N2
2 MG.11.G1.02 - VLT®is a registered Danfoss trademark
1

1.1.1. Introduction
The frequency converter control board is program selectable for use with the Johnson controls
Metasys N2 protocol. Metasys N2 is a master/slave control network. The physical layer is RS-485
compatible, half duplex 9600 baud shielded twisted pair. The N2 software protocol is designed to
be general in nature to accommodate the unique properties each device type may have. Every
device connection to the N2 network can be thought of as a small data manager. Data points in
the database are classified as analog I/O (floating point), binary I/O or integer data points - floats,
integers or bytes. Each data type has its own unique structure defined in the Metasys N2 system
Protocol Specification for Vendors.
The information in this manual is intended to provide you with comprehensive information on how
to install and set up the frequency converter for communication over a Metasys network.
For specific information on operation of the drive, refer to the
VLT
®
HVAC Drive Operating In-
structions, MG.11.Ax.yy.
1.1.2. About this Manual
This manual is for both instructional and for reference purposes. This manual can also serve as a
guideline when you specify and optimize your communication system.
It is highly recommended that you read this manual in its entirety before initiating any program-
ming. It is assumed that the user has full knowledge of the capabilities and limitation of the
controller node in addition to full knowledge of the frequency converter.
1.1.3. References
In addition to this manual, the following two manuals should be consulted: VLT
®
HVAC Drive
Operating Instruction, MG.11.Ax.yy
and Johnson Controls METASYS N2 System Protocol Specifi-
cation for Vendors, Johnson Controls number 04-3402-22, rev A
.
VLT
®
HVAC Drive Metasys N2 1. Overview
MG.11.G1.02 - VLT®is a registered Danfoss trademark 3
1

2. Instructions VLT
®
HVAC Drive Metasys N2
4 MG.11.G1.02 - VLT®is a registered Danfoss trademark
2

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 5
2

Illustration 2.1: Bus termination switch
In order to avoid potential equalizing currents in the screen, earth the cable screen via terminal
61, which is connected to the frame via an RC-link.
Bus termination: The RS485 bus must be terminated by a resistor network at both ends. For this
purpose, set switch S801 on the control card to "ON". For more information, see the paragraph:
Switches S201, S202 and S801.
NB!
Communication protocol must be set to FC MC par. 8-30.
2. Instructions VLT
®
HVAC Drive Metasys N2
6 MG.11.G1.02 - VLT®is a registered Danfoss trademark
2

2.1.4. Error Codes
Error codes
Error Code 00 is issued after power up or after a time out where all overridden points
were released, as long as no Identify yourself command has been issued
by the master.
Error Code 01 is issued if the command is not supported or not known by the drive.
Error Code 02 is issued if the received telegram has a checksum error.
Error Code 03 is issued if the N2 telegram receive buffer exceeds 256 characters.
Error Code 05 is issued if the received N2 telegram is too long.
Error Code 10 is issued the data is out of expected range
Error Code 11 is issued when:
1. A point attributes or attribute bit is unused.
2. A point attributes or attribute bit is for JCI use only.
3. An internal data point attribute for current value can not be changed
while running
Error Code 12 is issued when:
1. The N2 master tries to change attribute 2 bit 6 "Current State" on a BO
and the drive is tripped.
2. The N2 master tries to change attribute 2 bit 6 "Current State" on a BO
and the drive is trip locked except for BO 5 "reset"
2.1.5. VLT Parameters
The following parameters may need to be manually set for each drive in the Metasys N2 network.
Refer to the Installation, Operation and Maintenance Manual for the frequency converter for pro-
gramming.
Parameter list
FC PARAMETER DESCRIPTION DEFAULT DESIRED SETTING
8-01 Control side Digital & Ctrl. Word
8-02 Control source FC Port FC Port
8-03 Control word timeout 60 s 1-18000 s
8-30 Protocol FC Metasys N2
8-31 Address 11-255
8-32 Baud rate 9600 Fixed to 9600
8-33 Parity Even, 1stop Fixed to No Parity, 1stop
8-37 Max Inter-char delay 25 s for Metasys N2
VLT
®
HVAC Drive Metasys N2 2. Instructions
MG.11.G1.02 - VLT®is a registered Danfoss trademark 7
2

2.1.6. General Commands (Acknowledged)
VLT Re-
sponse Com- mand Subcom- mand NPA Ob- ject no. Attribute Mes- sage Type Error Code Comments
ACK 0 4 - Poll Message
No Acknowledge -The slave is to respond with any
data points, analog or binary I/O
that have been flagged for COS
ACK 0 5 - Poll message
With Acknowledge -The slave is to respond with any
data points, analog or binary I/O
that have been flagged for COS
ACK 0 9 - Status update Mes-
sage -
Slave device must respond with de-
vice manufacturing model number
(Par. 621), days in service (Par.
600) and device status
ACK F - - Identify Device
Type -Slave device responds with an iden-
tification number of 10H to indicate
non JCI device
ACK 0 0 - Synch Time -The internal clock is syncronized by
this command
ACK, no ac-
tion 80- Upload -
Optional, no support in the fre-
quency converter
ACK, no ac-
tion 8 1 - Upload -Optional, no support in the fre- quency converter
ACK, no ac-
tion 8 3 - Upload Record - Optional, no support in the fre-
quency converter
ACK, no ac-
tion 8 4 - Upload Complete -Optional, no support in the fre- quency converter
ACK, no ac-
tion 90-Download-
Optional, no support in the fre-
quency converter
ACK, no ac-
tion 9 1 - Download -Optional, no support in the fre- quency converter
ACK, no ac-
tion 93-Download-
Record optional, no support in the
frequency converter
ACK, no ac-
tion 9 4 - Download Complete -Optional, no support in the fre- quency converter
NAK 0 1 - Read Memory 01 Slave device memory read based
on memory addresses
NAK 0 8 - Warm Start 01 JCI use only
Table 2.1: No Region, Attribute Number and -type in this table.
2. Instructions VLT
®
HVAC Drive Metasys N2
8 MG.11.G1.02 - VLT®is a registered Danfoss trademark
2

2.1.7. Analog Input Commands (Acknowledged)
VLT Re-
sponse Com- mand
Sub-
com-
mand
Re-
gion NPA Object no. Attrib- ute No. Attribute Message Type Comments
ACK 1 - 1 0-23 1Byte Read Analog
Input
Read Object Configura-
tion attribute associ-
ated with each individ-
ual point
ACK 1 - 1 0-23 2Byte Read Analog
Input
1) Read Object Status
attribute associated
with each individual
point
ACK 1 - 1 0-23 3Float Read Analog
Input
2) Read Analog Input
Value attribute associ-
ated with each individ-
ual point
ACK 1 - 1 0-23 8Float Read Analog
Input
Read Low Alarm attrib-
ute associated with
each individual point
ACK 1 - 1 0-23 9Float Read Analog
Input
Read Low Warning at-
tribute associated with
each individual point
ACK 1 - 1 0-23 10 Float Read Analog
Input
Read High Warning at-
tribute associated with
each individual point
ACK 1 - 1 0-23 11 Float Read Analog
Input
Read High Alarm attrib-
ute associated with
each individual point
ACK 1 - 1 0-23 12 Float Read Analog
Input
Read Differential attrib-
ute associated with
each individual point
ACK 2 - 1 0-23 1Byte Write Analog
Input
Write to Object Config-
uration attribute associ-
ated with each individ-
ual point
ACK 2 - 1 0-23 8Float Write Analog
Input
Write toLow Alarm Lim-
it attribute associated
with each individual
point
ACK 2 - 1 0-23 9Float Write Analog
Input
Write to Low Warning
Limit attribute associ-
ated with each individ-
ual point
ACK 2 - 1 0-23 10 Float Write Analog
Input
Write to High Warning
Limitattribute associ-
ated with each individ-
ual point
ACK 2 - 1 0-23 11 Float Write Analog
Input
Write to High Alarm
Limit attribute associ-
ated with each individ-
ual point
ACK 2 - 1 0-23 12 Float Write Analog
Input
Write to Differential at-
tribute associated with
each individual point
ACK, no ac-
tion 7 2 1 0-23 -Float Override Ana- log inputs
Analog inputs are "out-
puts" from the frequen-
cy converter and should
not be written over by
the network controller
ACK, no ac-
tion 7 3 1 0-23 - - Override Ana- log Release
Analog inputs are "out-
puts" from the frequen-
cy converter and should
not be written over by
the network controller
ACK, no ac-
tion 7 7 1 0-23 - - Write Analog Input Attributes
Optional command for
slave devices. Only
used for N2 commis-
sioning purposes
Table 2.2: No Error code in this table.
VLT
®
HVAC Drive Metasys N2 2. Instructions
MG.11.G1.02 - VLT®is a registered Danfoss trademark 9
2

2.1.8. Analog Input Commands (Not Acknowledged)
VLT
Re-
sponse
Com
man
d
Re-
gio
n
NPA Ob-
ject no. Attribu- te No. Attribute Mes- sage Type Er- ror
Cod
e
Comments
NAK 1 1 0-23 4Float Read Ana-
log Input 11
1 )
Read Linear Ranging
Parameter 1 attrib-
ute associated with
each individual
point. (JCI use only)
NAK 1 1 0-23 5Float Read Ana-
log Input 11
1)
Read Linear Ranging
Parameter 2 attrib-
ute associated with
each individual
point. (JCI use only)
NAK 2 - 0-23 2Byte Write Ana-
log Input 11
1)
Object Status write-
able
NAK 2 - 0-23 3Float Write Ana-
log Input 11
1)
Analog Input Value
not writeable
NAK 2 - 0-23 4Float Write Ana-
log Input 11
1)
Write to Linear
Ranging Parameter
1 attribute associ-
ated with each indi-
vidual point. (JCI use
only)
NAK 2 - 0-23 5Float Write Ana-
log Input 11
1)
Write to Linear
Ranging Parameter
2 attribute associ-
ated with each indi-
vidual point. (JCI use
only)
NAK 2 - 0-23 6Float Write Ana-
log Input 11
1)
Write to Linear
Ranging Parameter
3 attribute associ-
ated with each indi-
vidual point. (JCI use
only)
NAK 2 - 0-23 7Float Write Ana-
log Input 11
1)
Write to Linear
Ranging Parameter
4 attribute associ-
ated with each indi-
vidual point. (JCI use
only)
NAK 2 - 0-23 13 Inte-
ger Write Ana- log Input 11
1)
Write to Filter
Weight attribute as-
sociated with each
individual point. (JCI
use only)
NAK 2 - 0-23 14 Float Write Ana-
log Input 11
1)
Write to AI Offset at-
tribute associated
with each individual
point. (JCI use only)
1)
Error code 11 is used because attributes are considered as fields/records in the point map
database.
Table 2.3: No Subcommand coloumn in this table.
2. Instructions VLT
®
HVAC Drive Metasys N2
10 MG.11.G1.02 - VLT®is a registered Danfoss trademark
2