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Voltage channels. OPC Server. PDO Exchange. CANopen Master/Slave node. Object dictionary. Object dictionary. ELMB CANopen Slave node. SCADA System OPC Client. PC, VME, etc. Readout Chain. ELMB Digitization of analog inputs OPC Server Client-server architecture

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Readout Chain

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Readout chain

Voltage channels

OPC Server

PDO

Exchange

CANopen

Master/Slave

node

Object

dictionary

Object

dictionary

ELMB CANopen

Slave node

SCADA System

OPC Client

PC, VME, etc.

Readout Chain

  • ELMB

    • Digitization of analog inputs

  • OPC Server

    • Client-server architecture

    • Conversion to physical units

    • Standard connection for any OPC Client

  • PVSS

    • Fine calibration and data display

ELMB Course


Typical application

Typical Application

  • ELMB

    • 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 (15 + 9 mA/ELMB)

  • CAN Power Crate or commercial Power Supply

  • Patch panel

  • Rack (and wall) mounted ELMB motherboard

ELMB Course


Physical distribution

Rack Mounted

ELMBs

s ~ 5 m

s ~ 0.5 m

Physical Distribution

Kvaser

PCI-CAN

PS

USA15

UX15

Patch Panel

ELMB Course


The can bus

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


The elmb embedded local monitor board

Node ID DIP switches

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, 16-64 channelsInterlock 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

ELMB Course


Elmb motherboard

ELMB Motherboard

  • General purpose motherboard

    • Allows for signal adaptation

    • Connectors for analog and digital input and outputs

    • Power connector

    • CAN bus connector

ELMB Course


Motherboard bottom side

Motherboard Bottom Side

ELMB Course


Adapters

Adapters

  • Temperature sensors – 2 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


Motherboard top side

Motherboard Top Side

ELMB Course


Elmb 128 block diagram

ELMB 128 Block Diagram

ELMB Course


Powering

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


Installing kvaser card

Installing Kvaser Card

  • Download drivers from:www.kvaser.comThen 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


Kvaser 4 port can card

Kvaser 4-port CAN Card

  • SW-1

    • 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


Installing opc server and diagnostic software

Installing OPC Server(and diagnostic software)

  • Download setup zip file from:http://atlas.web.cern.ch/Atlas/GROUPS/DAQTRIG/DCS/ELMB/DIST/OPC/OPCSetup.zipor, for a self extracting zip file

    http://atlas.web.cern.ch/Atlas/GROUPS/DAQTRIG/DCS/ELMB/DIST/OPC/OPCSetupZip.exe

  • 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


Can canopen background

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


Canopen device model

CANopen device model

All device parameters are stored in anobject 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

Application

Program,

Device Profile

implementation

TxPDO

RxPDO

Communication

Interface

PDO, SDO, NMT

Process IO

NG

NMT

SYNC

EMCY

ELMB Course


Canopen communication model

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


Canopen communication objects

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


Canopen state model

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


Understanding the elmb messages nmt

Understanding the ELMB messages: NMT

NMT: change node state

COB-ID

0

1

2

0

cmd

nodeId

cmd: 0x01 => Start

0x02 => Stop

0x80 => Set to pre-operational

0x81 => Reset

0x82 => Reset CAN communication

ELMB Course


Understanding the elmb messages sync

Understanding the ELMB messages: SYNC

SYNC: request synchronous inputs from nodes

COB-ID

0

1

2

0x80

ELMB Course


Understanding the elmb messages sdo

Understanding the ELMB messages: SDO

SDO: read node configuration; SDO Upload

SDO Server

SDO Client

COB-ID

0

1

2

3

4

5

6

7

request

Indication

0x600 + ID

Sub-Idx

Index

0x40

COB-ID

0

1

2

3

4

5

6

7

0x580 + ID

Sub-Idx

data0

data1

data2

data3

Index

aaa

Confirmation

Response

aaa: 0x4f => 1 byte read

0x4b => 2 bytes read

0x43 => 4 bytes read

ELMB Course


Understanding the elmb messages sdo1

Understanding the ELMB messages: SDO

SDO: write node configuration; SDO Download

SDO Server

SDO Client

COB-ID

0

1

2

3

4

5

6

7

request

Indication

0x600 + ID

Sub-Idx

data0

data1

data2

data3

Index

aaa

COB-ID

0

1

2

3

4

5

6

7

0x580 + ID

Sub-Idx

Index

0x60

Confirmation

Response

aaa: 0x2f => 1 byte read

0x2b => 2 bytes read

0x23 => 4 bytes read

(If accessed values are unsigned)

ELMB Course


Understanding the elmb messages tpdo

Understanding the ELMB messages: TPDO

Tx-PDO1: read digital inputs from the ELMB

COB-ID

0

1

0x180 + ID

Port F

Port A

Tx-PDO3: read analog inputs from the ELMB. “Multiplexed” PDO

COB-ID

0

1

2

3

4

5

0x380 + ID

chN = 0

status

aaa

bbb

ccc

ddd

Value inmVolts

0x380 + ID

chN = 63

status

aaa

bbb

ccc

ddd

ELMB Course


Understanding the elmb messages rpdo

Understanding the ELMB messages: RPDO

Rx-PDO1: write digital outputs from the ELMB

COB-ID

0

1

0x200 + ID

Port C

Port A

ELMB Course


Saving elmb settings

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


Ole for process control opc

OLE for Process Control (OPC)

Items and Groups:

A Client/Server Architecture:

  • Server Address Space contains OPC Items

  • Client: Organize OPC Items in groups

  • (active, polling-rate, dead-band etc).

  • Server:

    • Holds process data

  • Client

    • Read/write/subscribe

  • Relation n-to-m.

Data Access Mechanism:

  • Synchronous.

  • Asynchronous.

  • Refresh.

  • Subscribe.

OPCClient 1

OPCClient 2

Address Space

Address Space

OPCGroup 1

OPCGroup 1

OPCGroup 2

OPCGroup 1

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

OPC Item

ProcessDataObjects

ProcessDataObjects

OPC Server 1

OPC Server 2

ELMB Course


Elmb canopen opc server

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 defaultaddress 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


Elmb opc default configuration

ELMB OPC default configuration

Items accessed via SDO

ELMB Course


Elmb opc default configuration 2

ELMB OPC default configuration (2)

Items not in the ELMB OD

[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


Elmb canopen opc server1

ELMB/CANopen OPC Server

COB-ID

0

1

2

3

4

5

0x380 + ID

chN = 11

status

aaa

bbb

ccc

ddd

Value inmVolts

ELMB Course


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