Telcom Regulatory/Recommendation/Standards overview
Hub
Office
Central
Office
GPS
Local Exchange Office
(LEC, CAP, CLEC)
Cell
Site
Backbone Networks
(SDH/SONET/DWDM)
Base Station
Controller
(BSC)
Hub
Office
Central
Office
ISP
Office
End
Office
Satellite
Ground Station
Cable TV
Office
Other
Networks
Mobile Telephone
Switching Office
(MTSO)
Inter-exchange
Office (IXC)
Submarine
Cable
Customer Premises
Equipment (CPE)
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Cloud to cloud lightning strike
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Cloud to ground lightning strike
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55
Characteristic of lightning waveform
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Double exponential waveform definition
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Application of Regulatory
Requirements
Central Office
Outside Plant
Subscriber
Premises
Customer Premises
Equipment (CPE)
Wall Plug, Network
Interface Device
(NID), POTS SPLITTER
TIA-968-A (formerly FCC Part 68)
ITU K.21
UL60950
UL 497
YD/T 993-1998
Street Cabinet,
SLIC APP if on
DLC system
O/H Cable
MDF
SLIC
MDF
SLIC
switch
trunk line
T1, HDSL,
or HDSL-2
U/G
Cable
GR 1089
ITU K.20
UL 60950
UL 497
YD/T 1082-2000
DDF
GR 1089
ITU K.20
UL 60950
UL 497
YD/T 950-1998
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58
Regulatory Requirements
• GR 1089
Issue 3 Oct 2003
– Electrical safety (surge and current limiting)
– LEC offices and CPE locations
• TIA-968-A
– Lightning
– Customer premises equipment (CPE)
• UL 60950
– surge
– power fault
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Regulatory Requirements
• ITU K.20 and .21
– Metallic and longitudinal surges
– Power fault
– Coordination issues
• YD/T 950-1998
– based on ITU K.20
• YD/T 993-1998
– based on ITU K.21
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GR 1089 Requirements for Telecom Port
• NRTL requirements
– All network equipment powered by AC
– equipment located on customer premises
• 1st level criteria
– EUT undamaged & continues to operate
• 2nd level criteria
– EUT may sustain damage
– no fire, fragmentation, electrical hazard
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GR 1089 Protection Coordination
(4.6.7.1)
• 1 Not required IF equipment can with
stand 10x1000 100A event
• 2 Otherwise primary must be shown to
turn on during surge events
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UL 60950 Power Fault (AKA IEC 60950 and
EN 60950
• L1-L5
– 600 volt, 40 A 1.5 seconds
– 600 volt, 7A 5 seconds
– 600 volt, 2.2A 30 minutes
– 200 volt, 2.2A 30 minutes
– 120 volt, 25A 30 minutes
• M1-M4
– similar to L1-4
• L1, L5, & M1 can not open MDL 2.0 fuse
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UL 60950 Creepage/Insulation
Requirements
• Shortest distance between two conductive
parts depends on pollution degree, working
voltage, board material
– or
• electric strength test (Section 5.3 table 18)
– 1kV or 1.5 kV hi pot event
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UL 60950 Separation Requirements
(Section 6.4)
• Meet either electric strength test
– 1.0 kV for 60 seconds
• or
• Meet impulse test:
– 2.5 kV, 62.5 A, 10x700
• or
– 1.0 kV, 37.5A 10x700
– applied 10 times with 60 second rest period
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TIA-968-A Surges
• Type A surges (can not HARM PSTN):
– metallic 800V 100A 10/560 2 times
– longitudinal 1500V 200A 10/160 2 times
• Type B surge (operational afterwards)
– metallic 1000V 25A 5/320 2 times
– longitudinal 1500V 37.5A 5/320 2 times
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ITU K.20/21
• K.20 covers central office type of equipment
• K.21 covers customer premises type of
equipment
• Two levels:
– Basic
– Enhanced
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ITU K.20/21 coordination
• Coordination with the primary
– not required for BASIC IF:
• capable of withstanding 8x20 1kA surge ± 5X
– not required for ENHANCED IF:
• capable of withstanding 8x20 5kA surge ±5X
• Coordination not required if primary is not
“specified” (the agreed to primary protector
clause)
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What do these Standards Mean?
• Over- voltage protection
– SIDACtor devices
– Gas Plasma devices
• Over-current protection
– TeleLink fuse
– PTC
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Technologies for protection
Central Office Site
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Application Circuits
•
•
•
•
•
•
T1/E1/J1
T3
xDSL (VDSL2+, ADSL2, ADSL, etc.
SLIC (Subscriber Line Interface Circuit)
Ethernet (10BaseT, 100BaseT, 1000BaseT)
ISDN (Japan version, USA version, European
version)
• Transformer protection
• POTS
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SIDACtor - What is it?
• Over-voltage Protection For:
–
–
–
–
–
Telecommunications Equipment
CATV Equipment
Security Systems
Data Communications
Thyristor Applications
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SIDACtor - How Does it Work?
• Turns on with voltage
• Turns off with current
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SIDACtor V-I Curve
+I
IT
IS
IH
IDRM
-V
+V
VT
VDRM
VS
-I
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Contact information
• Phillip Havens, Sr Member Technical Staff
– 972-518-9427
– phavens@littelfuse.com
– www.littelfuse.com
– 1800 Hurd Drive, Irving, TX 75038
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