International Telecommunication Union
ITU-T Study Group 05
Damage to equipment
in Japan
Tetsuya Tominaga
Technical Session on Home Networks
Geneva, 29/04/2011
Special Resistibility
(K.44, K.66)
ITU-T
Study Group 05
Basic level and Enhanced level of resistibility are described in
K.21, The special level is described in K.44 and K.66
Table II.6-1/K.44 – Resistibility and safety requirements of
customer premises equipment powered by mains power
TEST
Telecomm
Telecomm Telecomm
Telecomm
Mains
Mains
Mains unication Internal Internal
unication unication
unication
power
power
powMer –
line –
line
line
line
line
line –
longitudin transvers
Internal
Mains longitudin transvers
longitudin transvers
Internal
al
e
port
power
al
e
al
e
port
line
13 kV
Lightnin
10 kV
10 kV
10 kV 10/700
13 kV
4 kV
13 kV
Under
g Surge
combina combina
combina 10 kV
10/700 10/700
10/700
study
Test
tion
tion
tion combina
tion
Technical Session - Home Networks - Geneva
Under
study
Typical configuration of ONT/HGW
ITU-T
o ONT/HGW don’t have external telecom line.
o Why the lightning current flows into ONT/HGW?
Study Group 05
1 Optical fiber port
1 AC adaptor
4 Ether ports
2 POTS port
Fig.1 Typical ONT/HGW
Technical Session - Home Networks - Geneva
How many ONT/HGW were damaged?
It was not acceptable failure rates for 2kV type ONT/HGW
ITU-T
Study Group 05
o
o
o
6 types of ONT/HGW, total 3 million shipments
ONT/HGW has 2 POTS ports and 4 Ether ports
Observation period 2007-2009
The resistibility between AC mains to POTS are 7kV – 13 kV
1.000
Failure rates (%)
o
0.100
0.010
0.001
1
10
Resistibility level between POTS ports(kV)
Fig.1 Example of Relationship between resistibility and Failure rates
Technical Session - Home Networks - Geneva
What port is damaged in ONT/HGW?
ITU-T
70 damaged ONT/HGW were counted the damaged ports
Internal POTS port were damaged over 90%
Study Group 05
Table 1. Example for ratio of failure ports
Failure port
POTS *)
POTS + Ether
POTS + Ether + AC adaptor
Malfunction
Unknown
*) POTS is may also include other port failure
Ratio (%)
60
29
3
7
1
AC mains – POTS :10kV
AC mains port differential : 2kV
Between POTS: 1kV
Num =70
Technical Session - Home Networks - Geneva
Example of damaged ONT/HGW
in the field(1)
ITU-T
o Protector elements on POTS ports were damaged
Study Group 05
TEL1
SLIC
TEL2
Damaged
Technical Session - Home Networks - Geneva
Example of damaged ONT/HGW
in the field(2)
ITU-T
Study Group 05
o Subscriber Line Card Module and protector
elements were damaged
o Sometimes RJ11 were damaged and burned
Damaged
TEL1
TEL2
Damaged
Damaged
RJ11
Technical Session - Home Networks - Geneva
Lightning surge flows into
ONT/HGW
Study Group 05
o These equipment has AC mains port or individual
grounding
1 Optical fiber port
1 AC adaptor
POTS toPOTS toEther to
POTS Ether Ether
ITU-T
o Lightning surge flows port to port
4 Ether ports
2 POTS port
AC port to POTS port
Fig.1 Typical ONT/HGW
Technical Session - Home Networks - Geneva
Configuration and current flow (1)
o Case 1: Damage occurred between mains power port and
internal port
ITU-T
Study Group 05
o
o
Damage: Home Gate Way & Telephone
Route: AC mains (1)—AC/DC Adaptor—HGW—Telephone—AC mains
(2)
Ethernet port
Customer Premises
Lightning surge
Optical line port
＜ Equipment＞
Optical Fiber
ONU
d.c.
WAN
HGW
Internal port
a.c. mains
AC/DC
Adapter
Mains power
port
Telecom
equipment
a.c. mains
Annex building
ONU : Optical Network Unit
HGW: Home Gateway
SPD : Surge Protective Device
Technical Session - Home Networks - Geneva
Configuration and current flow(2)
o
ITU-T
o
o
Case 2: Damage occurred between two internal ports of telecom. equipment
Damage: Telecom. Equip 1 (FAX), Home Gate Way & Telecom. Equip 2 (PC)
Route: AC mains (1)–Telecom. Equip 1–HGW–Telecom. Equip 2–SPD–Local PE
Study Group 05
Customer Premises
Mains power
port
L１
N
Lightning surge
AC/DC Adapter
Optical line port
Optical Fiber
d.c.
L１
ONU/HGW
N
Internal port
Internal port
L2
Telecom equipment 1
N
L2
Telecom
equipment 2
SPD
SPD
Washing machine
Protective earth
Technical Session - Home Networks - Geneva
Near Future? / Already Now?
ITU-T
Smart appliance connects to Home Gateway.
Many kinds of equipment will be connected each other.
Study Group 05
Smart Meter
Optic
Fiber
SPD：Surge Protective Device
Technical Session - Home Networks - Geneva
Bad installation and insufficient
resistibility
ITU-T
Good installation and Adequate resistibility are needed.
Study Group 05
Smart Meter
Optic
Fiber
SPD：Surge Protective Device
Technical Session - Home Networks - Geneva
Conclusion
ITU-T
Study Group 05
• Failure rates is over 0.1 %@2kV and 0.01 %@7kV.
• Adequate test levels is needed for Internal Port to Internal
Port for ONT/HGW
Table II.6-1/K.44 – Resistibility and safety requirements of
customer premises equipment powered by mains power
TEST
Telecomm
Telecomm Telecomm
Telecomm
Mains
Mains
Mains unication Internal Internal
unication unication
unication
power
power
powMer –
line –
line
line
line
line
line –
longitudin transvers
Internal
Mains longitudin transvers
longitudin transvers
Internal
al
e
port
power
al
e
al
e
port
line
13 kV
Lightnin
10 kV
10 kV
10 kV 10/700
13 kV
4 kV
13 kV
Under
g Surge
combina combina
combina 10 kV
10/700 10/700
10/700
study
Test
tion
tion
tion combina
tion
Technical Session - Home Networks - Geneva
Under
study