1. Readout Chain ELMB OPC Server PVSS Digitization of analog inputs
Client-server architecture
Conversion to physical units
Standard connection for any OPC Client
PVSS
Fine calibration and data display
CANopen
Master/Slave
node
dictionary
Object
ELMB CANopen
Slave node
Voltage channels
OPC Server
PC, VME, etc.
PDO
Exchange
SCADA System
OPC Client
ELMB Course

2. Typical Application ELMB Kvaser PCI card (2 or 4 port)
Maximum of 32 ELMBs in a branch
Kvaser PCI card (2 or 4 port)
CANbus cable from USA15 or US15 to UX15
TIS qualified
Shielded
Length ≈ 150m
Including remote powering, 7 lines:
GND
CAN signals
CAN power (20 mA/ELMB)
Digital + Analog power ( mA/ELMB)
CAN Power Crate or commercial Power Supply
Patch panel
Rack (and wall) mounted ELMB motherboard
ELMB Course

3. Physical Distribution
Kvaser
PCI-CAN PS
USA15
UX15
Rack Mounted
ELMBs
s ~ 5 m
s ~ 0.5 m
Patch Panel
ELMB Course

4. The CAN Bus Each node must have a unique ID
0 reserved; applies to all nodes in the CANbus
Both ends of bus must be terminated
120 ohm resistor between CAN_H and CAN_L
Straight Bus configuration
Star or Ring configurations are not possible
Maximum of 63 ELMBs per bus
Recommended maximum of 32 per bus
Configurable baud rate
Faster rates restrict bus length
125 Kbaud ≈ 500m
250 Kbaud ≈ 270m
ELMB Course

5. The ELMB (Embedded Local Monitor Board)
General purpose CAN node using CANopen
Flexible I/O functions
Multiplexed ADC, 16 bit, 64 channels with signal adaptation. Configurable for rate, range, mode and number of channels
8 input, 8 output and 8 definable I/O ports
SPI bus
Low power consumption, opto-isolated
Add-ons: DAC, 12 bit, channels Interlock facility
Data sent periodically, on-request or on-change
Radiation tolerant
0.5 Gy and 3*1010 neutrons per year
Operation in field of 1.5 Tesla
Remote diagnostics and loading of SW
SEE detection and recovery
Node ID DIP switches
ELMB Course

6. ELMB Motherboard General purpose motherboard
Allows for signal adaptation
Connectors for analog and digital input and outputs
Power connector
CAN bus connector
ELMB Course

7. Motherboard Bottom Side
ELMB Course

8. Adapters Temperature sensors – 2 wire Temperature sensors – 4 wire
For NTC 10K or PT1000
Temperature sensors – 4 wire
For PT100
Differential voltage attenuator
Attenuates 1:100
Inline resistors
1Kohm resistors for simple voltage measurement
Resistor values on adapters may be modified
for greater accuracy over a known voltage range
ELMB Course

9. Motherboard Top Side
ELMB Course

10. ELMB 128 Block Diagram
ELMB Course

11. Powering Ways to power the ELMB
CAN and Digital power supplied through the CAN bus
Need to connect Analog power to Digital or CAN
Recommended to connect Analog power to Digital as CAN draws more current
Useful for highly distributed systems
Supply power through motherboard using up to three different supplies
Possible to connect the three power sections together and supply only one voltage (not recommended)
ELMB Course

12. Installing Kvaser Card
Download drivers from: Then go to ‘Support ▼’, ‘Downloads’ and under heading ‘Files for specific products’ click ‘Files for PCIcan’
Run setup program
Shut-down PC
Check switches (SW-1 and SW-2) on CAN card and set as necessary (only for 4-port card)
Pay special attention to ‘common bus’
Install Kvaser card in free PCI slot
Start PC
Last setup steps will be completed
ELMB Course

13. Kvaser 4-port CAN Card SW-1 SW-2
To connect CAN ground to PC ground (switches 1 and 2 – switch 3 is unused)
SW-2
On-board terminators for “common bus” (switches 1 and 2)
Connection of ports to “common bus” (switches 3 to 10)
ELMB Course

14. Installing OPC Server (and diagnostic software)
Download setup zip file from: or, for a self extracting zip file
Unzip to temporary folder
Login as ‘Administrator’ to local PC
Do NOT login to network
Do NOT login with a different user name (even if the user has administration rights)
Run ‘setup.exe’ from the temporary folder
Install required components
Kvaser and/or NICAN component
Help files
Diagnostic Tools
OPC Server
ELMB Course

15. CAN/CANopen background
CAN is one of the three recommended fieldbuses at CERN
Defines two first layers of the OSI communication model
Physical: Communication medium
Data link: How the data frames look like
CANopen is a High-level communication protocol on top of CAN
Defines how CAN frames are used
CANopen chosen on the basis of its flexibility and acceptance
The ELMB framework will try to hide CAN/CANopen from the users
However, a small background on the technologies will help you to understand
why things have to be executed in a given sequence
ELMB Course

16. All device parameters are stored in an object dictionary.
CANopen device model
All device parameters are stored in an object dictionary.
The object dictionary contains the description, data type and structure of a parameter, as well as its address
CANopen device
SDO
Object Dictionary
Data types,
Communication
and application
objects
Application
Program,
Device Profile
implementation
TxPDO
RxPDO
Communication
PDO, SDO, NMT
Interface
Process IO NG
NMT
SYNC
EMCY
ELMB Course

17. CANopen communication model
Master-slave and slave-slave communication modes
The ELMB standard readout chain implements the master-slave model
PVSS application, using the OPC server, is CANopen master.
A CANopen master as a network manager
node configuration
network boot
supervision
ELMB Course

18. CANopen communication objects
CANopen communication objects can be classified in four categories
Process Data Objects (PDO):
Real time transfers
Unconfirmed in broadcast mode
Up to 8 data bytes
Two types:
Received (RxPDO): Outputs
Transmitted (TxPDO): Inputs
Service Data Objects (SDO):
Mainly used for device configuration
Access to object dictionary
Peer-to-peer
Confirmed data transfer of arbitrary length
Administrative Objects:
Network Management (NMT)
Node Guarding (NG)
Special Function Objects:
Network synchronization (SYNC)
Error conditions (EMCY)
Time stamping
ELMB Course

19. CANopen state model NMT = Stop SDO Stopped NMT = Reset NMT = Start SDO
PDO
NMT = Stop
Operational
SDO
NMT = Start
EMCY
Boot up
PDO
Pre-operational
NMT = Set to Pre-Op
Initial
PDO
Power up
OFF
NMT = Reset
ELMB Course

20. Understanding the ELMB messages: NMT
NMT: change node state
COB-ID 1 2
cmd
nodeId
cmd: 0x01 => Start
0x02 => Stop
0x80 => Set to pre-operational
0x81 => Reset
0x82 => Reset CAN communication
ELMB Course

21. Understanding the ELMB messages: SYNC
SYNC: request synchronous inputs from nodes
COB-ID 1 2
0x80
ELMB Course

22. Understanding the ELMB messages: SDO
SDO: read node configuration; SDO Upload
SDO Server
SDO Client
COB-ID 1 2 3 4 5 6 7
request
Indication
0x600 + ID
Sub-Idx
0x40
Index
COB-ID 1 2 3 4 5 6 7
0x580 + ID
Index
Sub-Idx
data0
data1
data2
data3
aaa
Confirmation
Response
aaa: 0x4f => 1 byte read
0x4b => 2 bytes read
0x43 => 4 bytes read
ELMB Course

23. Understanding the ELMB messages: SDO
SDO: write node configuration; SDO Download
SDO Server
SDO Client
COB-ID 1 2 3 4 5 6 7
request
Indication
0x600 + ID
Index
Sub-Idx
data0
data1
data2
data3
aaa
COB-ID 1 2 3 4 5 6 7
0x580 + ID
0x60
Index
Sub-Idx
Confirmation
Response
aaa: 0x2f => 1 byte read
0x2b => 2 bytes read
0x23 => 4 bytes read
(If accessed values are unsigned)
ELMB Course

24. Understanding the ELMB messages: TPDO
Tx-PDO1: read digital inputs from the ELMB
COB-ID 1
0x180 + ID
Port F
Port A
Tx-PDO3: read analog inputs from the ELMB “Multiplexed” PDO
COB-ID 1 2 3 4 5
0x380 + ID
chN = 0
status
aaa
bbb
ccc
ddd
Value in mVolts
0x380 + ID
chN = 63
status
aaa
bbb
ccc
ddd
ELMB Course

25. Understanding the ELMB messages: RPDO
Rx-PDO1: write digital outputs from the ELMB
COB-ID 1
0x200 + ID
Port C
Port A
ELMB Course

26. Saving ELMB settings
All configuration changes are written to the RAM
Volatile memory, i.e. lost when the program is reinitialized, e.g. power cut
When the program is initialized, default configuration parameters are read from the EEPROM
In order to make your changes permanent, you must explicitly save them
ELMB Course

27. OLE for Process Control (OPC)
A Client/Server Architecture:
Items and Groups:
Server:
Holds process data
Client
Read/write/subscribe
Relation n-to-m.
Server Address Space contains OPC Items
Client: Organize OPC Items in groups
(active, polling-rate, dead-band etc).
Data Access Mechanism:
Synchronous.
Asynchronous.
Refresh.
Subscribe.
OPC Client 1
OPC Client 2
Address Space
Address Space
OPC Group 1
OPC Group 1
OPC Group 2
OPC Group 1
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
OPC Item
Process Data Objects
Process Data Objects
OPC Server 1
OPC Server 2
ELMB Course

28. ELMB/CANopen OPC Server
Generic CAN and CANopen OPC server
Can be used with other CAN or CANopen devices
Additional functionality to ease the work with the ELMB
Default configuration
Configuration file describe the network topology
When the ELMB default configuration is used, the OPC server implements a default address space which contains all OPC items required by standard users
e.g. items for SYNC, NMT, some SDO, PDO for AI, DI and DO, NG, EMCY
ELMB Course

29. ELMB OPC default configuration
Items accessed via SDO
OPC Item
Description
OD Index, Subindex
Type
<bus>.<node>.hwVersion
Contains hardware version
1009, 0
VT_UI4
<bus>.<node>.swVersion
ELMB software version
100A, 0
BSTR
<bus>.<node>.serialNumber
Contains the serial number of the ELMB
3100, 0
<bus>.<node>.guardTime
Read only value set to 1000 (1s)
100C, 0
VT_UI2
<bus>.<node>.lifeTime
Life guarding timeout in seconds
100D, 0
VT_UI1
<bus>.<node>.rate
ADC conversion rate
2100, 2
<bus>.<node>.range
ADC range
2100, 3
<bus>.<node>.mode
ADC measurement mode
2100, 4
<bus>.<node>.channelMax
Highest ADC channel number in use
2100, 1
<bus>.<node>.aiTransmissionType
Transmission type for analog inputs
1802, 2
<bus>.<node>.aiEventTimer
Event timer for analog inputs
1802, 5
<bus>.<node>.diDebounceTimer
Debounce timer for digital inputs
2200, 0
<bus>.<node>.diTransmissionType
Transmission type for digital inputs
1800, 2
<bus>.<node>.diEventTimer
Event timer for digital inputs
1800, 5
<bus>.<node>.digitalInEnable
Enables asynchronous transmission of Digital Input signals
6005, 0
VT_BOOL
<bus>.<node>.initHigh
Can be set to initialize digital outputs high after a hard reset
2300, 0
<bus>.<node>.save
Saves configuration to EEPROM
1010, 1
<bus>.<node>.load
Loads default configuration from EEPROM
1011, 1
<bus>.<node>.Error
Current value of the error register
1001, 0
ELMB Course

30. ELMB OPC default configuration (2)
Items not in the ELMB OD
OPC Item
Description
Type
<bus>.<node>.State
Integer value indicating current operating state of ELMB
VT_UI1
<bus>.<node>.NMT
Allows Network ManagemenT commands to be given to the ELMB
<bus>.<node>.bootupMessage
Value increments when bootup message received from ELMB
VT_UI4
<bus>.<node>.ai_#
Analog Input Channel #
VT_UI2/VT_UI4[1]
<bus>.<node>.di_F_# (#-0..7)
Digital Inputs (ELMB Port F)
VT_BOOL
<bus>.<node>.do_C_# (#-0...7)
Digital Outputs (ELMB Port C)
<bus>.<node>.do_A_# (#-0...7)
Digital Outputs (ELMB Port A)
<bus>.<node>.emergencyErrorCode
Gives emergency error code of last emergency message
VT_UI2
<bus>.<node>.specificErrorCodeByte1
First byte of specific error code given in last emergency message (actual byte 3 of emergency message)
<bus>.<node>.specificErrorCodeByte2
Second byte of specific error code given in last emergency message (actual byte 4 of emergency message)
<bus>.<node>.specificErrorCodeByte3
Third byte of specific error code given in last emergency message (actual byte 5 of emergency message)
<bus>.<node>.specificErrorCodeByte4
Fourth byte of specific error code given in last emergency message (actual byte 6 of emergency message)
<bus>.<node>.specificErrorCodeByte5
Fifth byte of specific error code given in last emergency message (actual byte 7 of emergency message)
[1] The type of these items depends on the setFlag. If the setFlag is “counts” the type is VT_IU2, otherwise it is VT_UI4
ELMB Course

31. ELMB/CANopen OPC Server
COB-ID 1 2 3 4 5
0x380 + ID
chN = 11
status
aaa
bbb
ccc
ddd
Value in mVolts
ELMB Course