ESD CAN-T-Connector User manual

CAN-T-Connector
Manual
to Product C.1311.03
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 1 of 22
esd electronics gmbh
Vahrenwalder Str. 207 • 30165 Hannover • German
http://www.esd.eu
Phone: [phone] • Fax: [phone]

N O T E
T e information in t is document as been carefully c ecked and is believed to be entirely reliable.
esd makes no warranty of any kind wit regard to t e material in t is document, and assumes no
responsibility for any errors t at may appear in t is document. In particular descriptions and
tec nical data specified in t is document may not be constituted to be guaranteed product features
in any legal sense.
esd reserves t e rig t to make c anges wit out notice to t is, or any of its products, to improve
reliability, performance or design.
All rig ts to t is documentation are reserved by esd. Distribution to t ird parties, and reproduction
of t is document in any form, w ole or in part, are subject to esd's written approval.
© 2018 esd electronics gmb , Hannover
esd electronics gmb
Va renwalder Str. 207
30165 Hannover
Germany
P one: [phone]
Fax: [phone]
E-Mail: [email protected]
Internet: www.esd.eu
T is manual contains important information and instructions on safe and efficient
andling of t e CAN-T-Connector. Carefully read t is manual before commencing any
work and follow t e instructions.
T e manual is a product component, please retain it for future use.
Trademark Notices
CANopen® and CiA® are registered EU trademarks of CAN in Automation e.V.
All ot er trademarks, product names, company names or company logos used in t is manual are reserved
by t eir respective owners.
Page 2 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector

Document file: I:\Texte\Doku\MANUALS\CAN\T-Connector\CAN-T-Connector_Manual_en_13.odt
Date of print: 2018-01-16
Document type
number: DOC0800
Document History
T e c anges in t e document listed below affect c anges in t e ardware as well as c anges in
t e description of t e facts, only.
Rev. C apter C anges versus previous version Date
1.0 - First released version in Englis 2010-11-01
1.1
-Safety Instructions and Classification of Warning Messages and Safety
Instructions inserted
2017-04-26
1.2 Figure 2 new
2.1 C apter revised, note concerning s ielding inserted
2.1.1 New c apter: S ielding General Description
2.1.2 New c apter: Usage in Lig t Industrial Environment (Single Twisted Pair Cable)
2.1.3 New c apter: Usage in Heavy Industrial Environment (Double Twisted Pair Cable)
3.,4. CAN Wiring Hints an Trouble S ooting Guide inserted
5. C apter: Declaration of Conformity
6. Order Information moved and revised
1.2 2.1.1 -
2.1.3
C apters restructured and revised, Figure 5 new 2017-04-28
1.3
2.1.1 -
2.1.2
Figures revised (n.c. inserted)
2018-01-16
2.1.3 Description of t e usage of t e CAN-T-Connector and Figure revised
Tec nical details are subject to c ange wit out furt er notice.
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 3 of 22

Classification of Warning Messages and Safety Instructions
T is manual contains noticeable descriptions, warning messages and safety instructions, w ic
you must follow to avoid personal injuries or deat and property damage.
T is is t e safety alert symbol.
It is used to alert you to potential personal injury azards. Obey all safety messages
and instructions t at follow t is symbol to avoid possible injury or deat .
DANGER, WARNING, CAUTION
Depending on t e azard level t e signal words DANGER, WARNING or CAUTION are used to
ig lig t safety instructions and warning messages. T ese messages may also include a warning
relating to property damage.
DANGER
Danger statements indicate a azardous situation w ic , if not avoided, will result in
deat or serious injury.
WARNING
Warning statements indicate a azardous situation t at, if not avoided, could result in
deat or serious injury.
CAUTION
Caution statements indicate a azardous situation t at, if not avoided, could result in
minor or moderate injury.
NOTICE
Notice statements are used to notify people on azards t at could result in t ings ot er t an
personal injury, like property damage.
NOTICE
T is NOTICE statement contains t e general mandatory sign and gives information t at
must be eeded and complied wit for a safe use.
INFORMATION
INFORMATION
Notes to point out somet ing important or useful.
Page 4 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector

Safety Instructions
● W en working wit t e CAN-T-Connector follow t e instructions below and read t e manual carefully
to protect yourself from injury and t e CAN-T-Connector from damage.
● T e device is a built-in component. It is essential to ensure t at t e device is mounted in a way t at
cannot lead to endangering or injury of persons or damage to objects.
● Do not use damaged or defective cables to connect t e CAN-T-Connector and follow t e CAN wiring
ints in c apter: "Correct Wiring of Electrically Isolated CAN Networks".
● In case of damages to t e device, w ic mig t affect safety, appropriate and immediate measures
must be taken, t at exclude an endangerment of persons and domestic animals and property.
● Current circuits w ic are connected to t e device ave to be sufficiently protected against
azardous voltage (SELV according to EN 60950-1).
● T e CAN-T-Connector may only be driven by power supply current circuits, t at are contact
protected.
A power supply, t at provides a safety extra-low voltage (SELV) according to EN 60950-1, complies
wit t is conditions.
● T e device as to be securely installed before commissioning.
● Protect t e CAN-T-Connector from dust, moisture and steam.
● Protect t e CAN-T-Connector from s ocks and vibrations.
● T e CAN-T-Connector may become warm during normal use. Always allow adequate ventilation
around t e CAN-T-Connector and use care w en andling.
● Do not operate t e CAN-T-Connector adjacent to eat sources and do not expose it to unnecessary
t ermal radiation.
Qualified Personnel
T is documentation is directed exclusively towards personnel qualified in control and automation
engineering. T e installation and commissioning of t e product may only be carried out by qualified
personnel, w ic is aut orized to put devices, systems and electric circuits into operation according to
t e applicable national standards of safety engineering.
Intended Use
T e intended use of t e CAN-T-Connector is t e connection of modules to a bus system e.g. CAN.
T e guarantee given by esd does not cover damages w ic result from improper use, usage not in
accordance wit regulations or disregard of safety instructions and warnings.
● T e CAN-T-Connector is intended for indoor use only.
● T e operation of t e CAN-T-Connector in azardous areas, or areas exposed to potentially explosive
materials is not permitted.
● T e operation of t e CAN-T-Connector for medical purposes is pro ibited.
Service Note
T e CAN-T-Connector does not contain any parts t at require maintenance by t e user. T e CAN-T-
Connector does not require any manual configuration of t e ardware. Unaut orized intervention in t e
device voids warranty claims.
Disposal
Devices w ic ave become defective in t e long run ave to be disposed in an appropriate way or
ave to be returned to t e manufacturer for proper disposal. Please, make a contribution to
environmental protection.
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 5 of 22

Table of contents
Safety Instructions...........................................................................................................................5
1. Overview......................................................................................................................................7
1.1 View....................................................................................................................................... 7
1.2 Dimensions............................................................................................................................7
2. Connector Assignments................................................................................................................8
2.1 CAN....................................................................................................................................... 8
2.1.1 S ielding General Description.......................................................................................9
2.1.2 Usage in Lig t Industrial Environment (Single Twisted Pair Cable)...............................9
2.1.3 Usage in Heavy Industrial Environment (Double Twisted Pair Cable)..........................10
3. Correct Wiring of Electrically Isolated CAN Networks.................................................................11
3.1 Standards concerning CAN Wiring.......................................................................................11
3.2 Lig t Industrial Environment (Single Twisted Pair Cable).....................................................12
3.2.1 General Rules.............................................................................................................12
3.2.2 Cabling........................................................................................................................13
3.2.3 Branc ing....................................................................................................................13
3.2.4 Termination..................................................................................................................13
3.3 Heavy Industrial Environment (Double Twisted Pair Cable).................................................14
3.3.1 General Rules.............................................................................................................14
3.3.2 Device Cabling............................................................................................................15
3.3.3 Branc ing....................................................................................................................15
3.3.4 Termination..................................................................................................................15
3.4 Electrical Grounding.............................................................................................................16
3.5 Bus Lengt ...........................................................................................................................16
3.6 Examples for CAN Cables...................................................................................................17
3.6.1 Cable for lig t industrial Environment Applications (Two-Wire)....................................17
3.6.2 Cable for eavy industrial Environment Applications (Four-Wire)................................17
4. CAN Troubles ooting Guide.......................................................................................................18
4.1 Termination..........................................................................................................................18
4.2 Electrical Grounding.............................................................................................................19
4.3 S ort Circuit in CAN Wiring..................................................................................................19
4.4 CAN_H/CAN_L-Voltage ......................................................................................................19
4.5 CAN Transceiver Resistance Test........................................................................................20
4.6 Support by esd.....................................................................................................................20
5. Declaration of Conformity...........................................................................................................21
6. Order Information.......................................................................................................................22
Page 6 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector

Overview
1. Overview
T e CAN-T-Connector wit 2x DSUB9 female contact and 1x DSUB9 male contact is designed for
t e correct connection of modules to a bus system e.g. CAN.
1.1 View
Fig. 1: CAN-T-Connector view
1.2 Dimensions
Fig. 2: Dimensions of t e CAN-T-Connector
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 7 of 22
33.0
5 2 . 7
20.5
6 4 . 0
9-pin DSUB
female connectors
16.5
22.5
3 5 . 0
All dimensions in mm.
9-pin DSUB
male connector

Connector Assignments
2. Connector Assignments
2.1 CAN
INFORMATION
T e signals of t e CAN-T-Connector are connected t roug . T e pins of t e t ree
connectors are assigned wit t e same signals!
T e pin assignment depends on t e signals connected.
Connector: 9-pin DSUB connector 1x male and 2x female
Pin Position:
DSUB9 male: DSUB9 female:
Example for Pin Assignment (According to CiA 303, CANopen Recommendation):
Signal Pin Signal
reserved 1 6 (GND)
CAN_L 2 7 CAN_H
CAN_GND 3 8 reserved
reserved 4 9 reserved
(CAN_SHLD) 5
Signal Description:
CAN_L, CAN_H CAN signal lines
CAN_GND Reference potential of local CAN p ysical layer
(CAN_SHLD) Optional CAN s ield
(GND) Optional ground
reserved Reserved for future applications, do not connect!
NOTICE
Note t at t e metal s ells of t e DSUB connectors are not connected. T us, t e metal
s ells are not connected t roug t e CAN-T-Connector, see Figure 3!
Read c apter “S ielding General Description” on page 9 for furt er information.
Page 8 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
12345
6789
12345
6789

Connector Assignments
2.1.1 S ielding General Description
Fig. 3: Internal connection of t e CAN-T-Connector
In t e CAN-T-Connector t e metal s ells of t e DSUB connectors are not connected. T us, t e
metal s ells are not connected t roug t e CAN-T-Connector, see Figure 3.
2.1.2 Usage in Lig t Industrial Environment (Single Twisted Pair Cable)
In t e standard esd CAN cables (Single Twisted Pair Cable, 2-wire + S ied) for lig t industrial
environment applications (see Figure 4), t e cable s ield (braided s ield) is used as signal
CAN_GND, but t is signal is not connected to t e metal s ell of t e DSUB9 connectors.
Instead, t e CAN_GND signal is connected to Pin 3. T erefore t e CAN-T-Connector is compatible
wit t e standard esd CAN cables.
Fig. 4: Internal connection of t e CAN-T-Connector using single twisted pair cable
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 9 of 22
CAN_H
CAN_GND
CAN_L
CAN_H
CAN_GND
CAN_L
Braided Shield
Metal Shell
Braided Shield
Metal Shell
Braided Shield
Metal Shell
n. .
n. . n. .
n. . ... not onne ted
.
.
.
1 2 3 9...
. . .
1
2
3
.
.
.
9
1
2
3
.
.
.
9
Metal S ell
Metal S ell Metal S ell
n. . ... not onne ted
n. .
n. .
n. .

Connector Assignments
2.1.3 Usage in Heavy Industrial Environment (Double Twisted Pair
Cable)
W en using t e esd’s CAN-T-Connector type C.1311.03 wit single s ielded double twisted pair
cables in eavy industrial environment applications, please note t at t e s ield potential of t e
conductive DSUB ousing is not looped t roug t is CAN-T-connector type (see also c apter
“Device Cabling” page 15).
T us, t e braided s ields of t e CAN cables ave to be connected to an external s ield
connection, for example via clamp straps (see Figure 5), to connect t e s ield potentials of t e
cables.
Fig. 5: Internal connection of t e CAN-T-Connector using double twisted pair cable
Page 10 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
CAN_H
CAN_GND
CAN_L
CAN_H
CAN_GND
CAN_L
Braided Shield
Metal Shell
Braided Shield
Metal Shell
Braided Shield
Metal Shell
External shield onne tion
Connect for example
via clamp strap
for s ield connection
Connect for example
via clamp strap
for s ield connection
Connect for example
via clamp strap
for s ield connection
Optional Earthing
n. .
n. . n. .
n. . ... not onne ted

Correct Wiring of Electrically Isolated CAN Networks
3. Correct Wiring of Electrically Isolated CAN Networks
NOTICE
T is c apter applies to CAN networks wit bit rates up to 1 Mbit/s.
If you work wit ig er bit rates, as for example used for CAN FD, t e information given
in t is c apter must be examined for applicability in eac individual case.
For furt er information refer to t e CiA® CAN FD guidelines and recommendations
(ttps://www.can-cia.org/).
For t e CAN wiring all applicable rules and regulations (EU, DIN), e.g. regarding electromagnetic
compatibility, security distances, cable cross-section or material, ave to be observed.
3.1 Standards concerning CAN Wiring
T e flexibility in CAN network design is one of t e key strengt s of t e various extensions and
additional standards like e.g. CANopen, ARINC825, DeviceNet and NMEA2000 t at ave been
built on t e original ISO 11898-2 CAN standard. In using t is flexibility comes t e responsibility of
good network design and balancing t ese tradeoffs.
Many CAN organizations and standards ave scaled t e use of CAN for applications outside t e
original ISO 11898. T ey ave made system level tradeoffs for data rate, cable lengt , and
parasitic loading of t e bus.
However for CAN network design margin must be given for signal loss across t e complete system
and cabling, parasitic loadings, network imbalances, ground offsets against eart potential and
signal integrity. T erefore t e practical maximum number of nodes, bus lengt and stub
lengt are typically muc lower.
esd as concentrated er recommendations concerning CAN wiring on t e specifications of t e
ISO 11898-2. T us t is wiring ints forgoes to describe t e special features of t e derived
standards CANopen, ARINC825, DeviceNet and NMEA2000.
T e consistent compliance to ISO 11898-2 offers significant advantages:
●Durable operation due to well proven design specifications
●Minimizing potential failures due to sufficient margin to p ysical limits
●Trouble-free maintenance during future network modifications or during fault diagnostics
due to lack of exceptions
Of course reliable networks can be designed according t e specifications of CANopen, ARINC825,
DeviceNet and NMEA2000, owever it must be observed t at it is strictly not recommended
to mix t e wiring guidelines of t e various specifications!
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 11 of 22

Correct Wiring of Electrically Isolated CAN Networks
3.2 Lig t Industrial Environment (Single Twisted Pair Cable)
3.2.1 General Rules
NOTICE
esd grants t e EU Conformity of t e product, if t e CAN wiring is carried out wit at least
single s ielded single twisted pair cables t at matc t e requirements of ISO 11898-2.
Single s ielded double twisted pair cable wiring as described in c apter 3.3. ensures t e
EU Conformity as well.
T e following general rules for CAN wiring wit single s ielded single twisted pair cable s ould be
followed:
1A cable type wit a wave impedance of about 120 Ω ±10% wit an adequate conductor cross-section
(≥ 0.22 mm²) as to be used. T e voltage drop over t e wire as to be considered.
2For lig t industrial environment use at least a two-wire CAN cable.
Connect
•
•
t e two twisted wires to t e data signals (CAN_H, CAN_L) and
t e cable s ield to t e reference potential (CAN_GND).
3T e reference potential CAN_GND as to be connected to t e functional eart (FE) at exactly one
point.
4A CAN net must not branc (exception: s ort cable stubs) and as to be terminated wit t e
c aracteristic impedance of t e line (generally 120 Ω ±10%) at bot ends (between t e signals CAN_L
and CAN_H and not at CAN_GND).
5Keep cable stubs as s ort as possible (l < 0.3 m).
6Select a working combination of bit rate and cable lengt .
7Keep away cables from disturbing sources. If t is cannot be avoided, double s ielded wires are
recommended.
Figure 6: CAN wiring for lig t industrial environment
Page 12 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
CAN GND
CAN_H
CAN_GND
n. .
CAN_L 1
4
5
6
7
9
2
3
8
9
1
4
5
6
7
3
8
2
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
earth (FE)
CAN_L
CAN_H
CAN_GND
Single shielded
twisted pair cable
(two-wire cable,
1x x 0. mm²)
CAN_GND
(at wire shield)
Wire Layout
Signal assignment of single shielded twisted pair cable
with earth and termination
n. . = not onne ted
DSUB9 connector
(female or male)
pin designation
connector case connector case
DSUB9 connector
(female or male)
pin designation
AN wire with connectors

Correct Wiring of Electrically Isolated CAN Networks
3.2.2 Cabling
●To connect CAN devices wit just one CAN connector per net use a s ort stub (< 0.3 m)
and a T-connector (available as accessory). If t is devices are located at t e end of t e
CAN network, t e CAN terminator “CAN-Termination-DSUB9” can be used.
Figure 7: Example for proper wiring wit single s ielded single twisted pair wires
3.2.3 Branc ing
●In principle t e CAN bus as to be realized in a line. T e participants are connected to t e
main CAN bus line via s ort cable stubs. T is is normally realised by so called T-
connectors. esd offers t e CAN-T-Connector (Order No.: C.1311.03)
●If a mixed application of single twisted and double twisted cables is unavoidable, take care
t at t e CAN_GND line is not interrupted!
●Deviations from t e bus structure can be realized by t e usage of repeaters.
3.2.4 Termination
●A termination resistor as to be connected at bot ends of t e CAN bus.
If an integrated CAN termination resistor w ic is equipped at t e CAN interface at t e end
of t e bus is connected, t is one as to be used for termination instead of an external CAN
termination plug.
●9-pin DSUB-termination connectors wit integrated termination resistor and male and
female contacts are available from esd (order no. C.1303.01).
●DSUB termination connectors wit male contacts (order no. C.1302.01) or female contacts
(order no. C.1301.01) and additional functional eart contact are available, if CAN
termination and grounding of CAN_GND is required.
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 13 of 22
CAN_L
CAN_GND
CAN_H
FE
CAN-DP/2CAN-CBX-DIO8 CAN-CBX-AI420
l
< 0,3 m
l
< 0,3 m
l
< 0,3 m
Female Conne tor
Male Conne tor
Terminator
with FE onne tor
Female Terminator
(Order-no.: C.1301.01)
T-Conne tor
C.1311.03
CAN able
Order-no.: C.1323.03
CAN 0
CAN 1 T-Conne tor
C.1311.03
T-Conne tor
C.1311.03
CAN Board
CAN able
Order-no.: C.1323.03
CAN able
Order-no.: C.1323.03
Termination onne tor
"CAN-Termination-DSUB"
Order-no.: C.1303.01
Termination onne tor
"CAN-Termination-DSUB"
with femal and male onta ts
(Order-no.: C.1303.01)
e.g.
CAN-PCIe/402,
PMC-CAN/400,
CAN-USB/2, et .
CAN_GND onne ted
to fun tional earth (FE)
at exa tly one point

Correct Wiring of Electrically Isolated CAN Networks
3.3 Heavy Industrial Environment (Double Twisted Pair Cable)
3.3.1 General Rules
T e following general rules for t e CAN wiring wit single s ielded double twisted pair cable
s ould be followed:
1A cable type wit a wave impedance of about 120 Ω ±10% wit an adequate conductor cross-section
(≥ 0.22 mm²) as to be used. T e voltage drop over t e wire as to be considered.
2For eavy industrial environment use a four-wire CAN cable.
Connect
•
•
•
two twisted wires to t e data signals (CAN_H, CAN_L) and
t e ot er two twisted wires to t e reference potential (CAN_GND) and
t e cable s ield to functional eart (FE) at least at one point.
3T e reference potential CAN_GND as to be connected to t e functional eart (FE) at exactly one
point.
4A CAN bus line must not branc (exception: s ort cable stubs) and as to be terminated wit t e
c aracteristic impedance of t e line (generally 120 Ω ±10%) at bot ends (between t e signals CAN_L
and CAN_H and not to CAN_GND).
5Keep cable stubs as s ort as possible (l < 0.3 m).
6Select a working combination of bit rate and cable lengt .
7Keep away CAN cables from disturbing sources. If t is can not be avoided, double s ielded cables are
recommended.
Figure 8: CAN wiring for eavy industrial environment
Page 14 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
CAN GND
CAN_L
CAN_H
CAN_GND
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
n. .
CAN_L
CAN_H CAN_GND
Shield
CAN_GND
twisted twisted
5
6
7
9
8
1
4
3
2
9
1
4
5
6
7
3
8
2
n. .
n. .
Single shielded
double twisted pair cable
(four-wire cable,
x x 0. mm²)
wire shield
Wire Layout
(Example)
Signal assignment of single shielded double twisted pair cable
with earth and termination
n. . = not onne ted
DSUB9 connector
(female or male)
pin designation
connector case
DSUB9 connector
(female or male)
pin designation
AN cable with connectors
connector case
earth (FE)

Correct Wiring of Electrically Isolated CAN Networks
3.3.2 Device Cabling
Figure 9: Example of proper wiring wit single s ielded double twisted pair cables
3.3.3 Branc ing
●In principle t e CAN bus as to be realized in a line. T e participants are connected to t e
main CAN bus line via s ort cable stubs. T is is normally realised by so called T-
connectors. W en using esd's CAN-T-Connector (order no.: C.1311.03) it s ould be noted
t at t e s ield potential of t e conductive DSUB ousing is not looped t roug t is T-
Connector type. T us t e s ielding is interrupted. T erefore you ave to take adequate
measures to connect t e s ield potentials, as described in t e manual of t e CAN-T-
Connector. For furt er information on t is read t e CAN-T-Connector Manual (order no.:
C.1311.21).
Alternatively a T-connector can be used, in w ic t e s ield potential is looped t roug , e.g.
t e DSUB9 connector from ERNI (ERBIC CAN BUS MAX, order no.:154039).
●If a mixed application of single twisted and double twisted cables is unavoidable, take care
t at t e CAN_GND line is not interrupted!
●Deviations from t e bus structure can be realized by t e usage of repeaters.
3.3.4 Termination
●A termination resistor as to be connected at bot ends of t e CAN bus.
If an integrated CAN termination resistor w ic is equipped at t e CAN interface at t e end
of t e bus is connected, t is one as to be used for termination instead of an external CAN
termination plug.
●9-pin DSUB-termination connectors wit integrated termination resistor and male and
female contacts are available from esd (order no. C.1303.01).
●9-pin DSUB-connectors wit integrated switc able termination resistor can be ordered e.g.
from ERNI (ERBIC CAN BUS MAX, female contacts, order no.:154039).
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 15 of 22

Correct Wiring of Electrically Isolated CAN Networks
3.4 Electrical Grounding
●For CAN devices wit electrical isolation t e CAN_GND must be connected between t e
CAN devices.
●CAN_GND s ould be connected to t e eart potential (FE) at exactly one point of t e
network.
●Eac CAN interface with electrical connection to earth potential acts as a grounding point.
For t is reason it is recommended not to connect more t an one CAN device with electrical
connection to earth potential.
●Grounding can be made e.g. at a termination connector (e.g. order no. C.1302.01 or
C.1301.01).
3.5 Bus Lengt
NOTICE
Please note t at t e cables, connectors and termination resistors used in CANopen
networks s all meet t e requirements defined in ISO11898-2.
In addition, furt er recommendations of t e CiA, like standard values of t e cross
section, depending on t e cable lengt , are described in t e CiA recommendation
CiA 303-1 (see CiA 303 CANopen Recommendation - Part 1: „Cabling and connector pin
assignment“, Version 1.8.0, Table 2).
Bit-Rate
[kbit/s]
T eoretical values of
reac able wire lengt
wit esd interface lmax
[m]
CiA recommendations
(07/95) for reac able
wire lengt s lmin
[m]
Standard values of
t e cross-section
according to
CiA 303-1
[mm²]
1000 37 25 0,25 to 0,34
800
666,6
500
333,3
250
59
80
130
180
270
50
-
100
-
250
0,34 to 0,6
166
125
420
570
-
500 0,5 to 0,6
100
83,3
66,6
50
710
850
1000
1400
650
-
-
1000
0,75 to 0,8
33,3
20
12,5
10
2000
3600
5400
7300
-
2500
-
5000
not defined in
CiA 303-1
Table 1: Recommended cable lengt s at typical bit rates (wit esd-CAN interfaces)
●Optical couplers are delaying t e CAN signals. esd modules typically reac a wire lengt of
37 m at 1 Mbit/s wit in a proper terminated CAN network wit out impedance disturbances
like e.g. caused by cable stubs > 0.3 m.
Page 16 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector

Correct Wiring of Electrically Isolated CAN Networks
3.6 Examples for CAN Cables
esd recommends t e following two-wire and four-wire cable types for CAN network design. T ese
cable types are used by esd for ready-made CAN cables, too.
3.6.1 Cable for lig t industrial Environment Applications (Two-Wire)
Manufacturer Cable Type
U.I. LAPP GmbH
Sc ulze-Delitzsc -Straße 25
70565 Stuttgart
Germany
www.lappkabel.com
e.g.
UNITRONIC ®-BUS CAN UL/CSA (1x 2x 0.22)
(UL/CSA approved) Part No.: 2170260
UNITRONIC ®-BUS-FD P CAN UL/CSA (1x 2x 0.25)
(UL/CSA approved) Part No.: 2170272
ConCab GmbH
Äußerer Eic wald
74535 Main ardt
Germany
www.concab.de
e. g.
BUS-PVC-C (1x 2x 0.22 mm²) Order No.: 93 022 016 (UL appr.)
BUS-Sc leppflex-PUR-C (1x 2x 0.25 mm²) Order No.: 94 025 016 (UL appr.)
3.6.2 Cable for eavy industrial Environment Applications (Four-Wire)
Manufacturer Cable Type
U.I. LAPP GmbH
Sc ulze-Delitzsc -Straße 25
70565 Stuttgart
Germany
www.lappkabel.com
e.g.
UNITRONIC ®-BUS CAN UL/CSA (2x 2x 0.22)
(UL/CSA approved) Part No.: 2170261
UNITRONIC ®-BUS-FD P CAN UL/CSA (2x 2x 0.25)
(UL/CSA approved) Part No.: 2170273
ConCab GmbH
Äußerer Eic wald
74535 Main ardt
Germany
www.concab.de
e. g.
BUS-PVC-C (2x 2x 0.22 mm²) Order No.: 93 022 026 (UL appr.)
BUS-Sc leppflex-PUR-C (2x 2x 0.25 mm²) Order No.: 94 025 026 (UL appr.)
INFORMATION
Ready-made CAN cables wit standard or custom lengt can be ordered from esd.
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 17 of 22

CAN Troubles ooting Guide
4. CAN Troubles ooting Guide
T e CAN Troubles ooting Guide is a guide to find and eliminate t e most frequent ardware-error
causes in t e wiring of CAN networks.
Figure 10: Simplified diagram of a CAN network
4.1 Termination
T e termination is used to matc impedance of a node to t e impedance of t e transmission line
being used. W en impedance is mismatc ed, t e transmitted signal is not completely absorbed by
t e load and a portion is reflected back into t e transmission line. If t e source, transmission line
and load impedance are equal t ese reflections are avoided. T is test measures t e series
resistance of t e CAN data pair conductors and t e attac ed terminating resistors.
To test it ,please
1. Turn off all power supplies of t e attac ed CAN nodes.
2. Measure t e DC resistance between CAN_H and CAN_L at one end of
t e network (see figure above).
T e measured value s ould be between 50 Ω and 70 Ω.
If t e value is below 50 Ω, please make sure t at:
- t ere is no s ort circuit between CAN_H and CAN_L wiring
- t ere are not more t an two terminating resistors connected
- t e nodes do not ave faulty transceivers.
If t e value is ig er t an 70 Ω, please make sure t at:
- t ere are no open circuits in CAN_H or CAN_L wiring
- your bus system as two terminating resistors (one at eac end) and t at t ey are 120 Ω
eac .
Page 18 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
120

CAN_H
CAN_GND
CAN_L
CAN_L
CAN_H
CAN_GND
V
2 3
1
V

120

1

CAN Troubles ooting Guide
4.2 Electrical Grounding
T e CAN_GND of t e CAN network s ould be connected to t e functional eart potential (FE) at
only one point. T is test will c eck if t e CAN_GND is grounded in several places.
To test it, please
1.
2.
3.
Disconnect t e CAN_GND from t e eart
potential (FE).
Measure t e DC resistance between
CAN_GND and eart potential (see figure
on t e rig t).
Reconnect CAN_GND to eart potential.
Figure 11: Simplified sc ematic diagram of
ground test measurement
T e measured resistance s ould be ig er t an 1 MΩ. If it is lower, please searc for additional
grounding of t e CAN_GND wires.
4.3 S ort Circuit in CAN Wiring
A CAN bus mig t possibly still be able to transmit data if t ere is a s ort circuit between CAN_GND
and CAN_L, but generally t e error rate will increase strongly. Make sure t at t ere is no s ort
circuit between CAN_GND and CAN_L!
4.4 CAN_H/CAN_L-Voltage
Eac node contains a CAN transceiver t at outputs differential signals. W en t e network
communication is idle t e CAN_H and CAN_L voltages are approximately 2.5 V measured to
CAN_GND. Faulty transceivers can cause t e idle voltages to vary and disrupt network
communication.
To test for faulty transceivers, please
1. Turn on all supplies.
2. Stop all network communication.
3. Measure t e DC voltage between CAN_H and CAN_GND
(see figure at previous page).
4. Measure t e DC voltage between CAN_L and CAN_GND
(see figure at previous page).
Normally t e voltage s ould be between 2.0 V and 3.0 V.
CAN-T-Connector Manual • Doc. No.: C.1311.21 / Rev. 1.3 Page 19 of 22
>1M 
CAN_H
CAN_GND
CAN_L

functional earth
(FE)
2
3

CAN Troubles ooting Guide
If it is lower t an 2.0 V or ig er t an 3.0 V, it is possible t at one or more nodes ave faulty
transceivers. For a voltage lower t an 2.0 V please c eck CAN_H and CAN_L conductors for
continuity.
To find t e node wit a faulty transceiver wit in a network please test t e CAN transceiver
resistance (see below) of t e nodes.
4.5 CAN Transceiver Resistance Test
CAN transceivers ave circuits t at control CAN_H and CAN_L. Experience as s own t at
electrical damage of t e circuits may increase t e leakage current in t ese circuits.
To measure t e current leakage t roug t e CAN circuits, please use a resistance measuring
device and:
1. Switc off t e node and disconnect it from t e network
(see figure below).
2. Measure t e DC resistance between CAN_H and CAN_GND
(see figure below).
3. Measure t e DC resistance between CAN_L and CAN_GND
(see figure below).
T e measured resistance as to be about 500 kΩ for eac signal. If it is muc lower, t e CAN
transceiver it is probably faulty.
Anot er indication for a faulty transceiver is a very ig deviation between t e two measured input
resistances (>> 200 %).
Figure 12: Measuring t e internal resistance of CAN transceivers
4.6 Support by esd
If you ave executed t e fault diagnostic steps of t is troubles ooting guide and you even can not
find a solution for your problem our support department will be able to assist.
Please contact our support via email at [email protected] or by p one [phone].
Page 20 of 22 Manual • Doc. No.: C.1311.21 / Rev. 1.3 CAN-T-Connector
4
5
6
CAN_H
CAN_GND
CAN_L
5 6
4
4
Power

CAN
transceiver
dis onne t
power!
dis onne t
CAN!
CAN node