The FT600 fuse series is designed to assist telecommunications
equipment manufacturers in complying with North American
overcurrent protection requirements, including Telcordia GR-
1089, TIA-968-A (formerly FCC Part 68), and UL60950
3rd edition.
The low profile and small footprint of the FT600 fuse provide
a reliable, non-resettable overcurrent protection solution. The
device offers low temperature-rise performance under sneak
current fault events to prevent damage to circuit traces or
multilayer boards. When used in conjunction with SiBar™
thyristor devices, it provides designers with a complete
overcurrent/overvoltage protection solution to help them comply
with regulatory standards.
This fuse offering complements the telecom resettable
PolySwitch device series for use in applications where
intervention is desired after an overcurrent fault.
Benefits
• High density placement in multi-port system designs
• Improved temperature rise performance over other
similar SMT fuse devices under sneak-current testing
• The FT600 in conjunction with a SiBar overvoltage
protection device, assists designers in meeting
regulatory standards with no additional series
components
Features
• Low profile and small footprint
• The lightning robust surface-mount fuse offers
overcurrent protection in case of power fault events
• Enables the design of equipment complying with
applicable telecom specifications including UL60950,
TIA-968-A (formerly FCC Part 68), and Telcordia
GR-1089
• Low resistance
Applications
• ADSL, ADSL2, ADSL2plus, SHDSL, VDSL linecards and modems
• T1/E1 systems
• Twisted-pair telecom ports requiring Telcordia GR-1089, UL60950 and FCC Part TIA-968-A
(formerly FCC Part 68) compliance
Telecom Fuses
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Key Device Selection Citeria
Faster Cooler Surface SiBar Thyristor
Application Specification Time-To-Open Temperature Surge Protectors*
Customer premises equipment, IT equipment UL 60950 FT600-0500 FT600-2000 TVBxxxSC-L
Analog modems, V.90 modems, TIA-968-A FT600-1250
ISDN modems, xDSL modems,
ADSL splitters, phone sets, fax machines,
answering machines, caller ID, internet
appliances, PBX systems, POS terminals, wall plugs
Access network equipment Telcordia GR-1089 FT600-1250 FT600-2000 TVBxxxSC-L
Remote terminals, line repeaters, multiplexers, TIA-968-A
cross-connects, WAN equipment
Central office switching equipment Telcordia GR-1089 FT600-1250 FT600-2000 TVBxxxSC-L
Analog/POTS linecards, ISDN linecards, xDSL modems, TIA-968-A
ADSL/VDSL splitters, T1/E1 linecards,
multiplexers, CSU/DSU, servers
Notes: This list is not exhaustive. Raychem Circuit Protection welcomes our customers’ input for additional application ideas for overcurrent protection of telecom applications.
* For more information on Raychem Circuit Protection SiBar thyristor surge protectors.
To use this guide, follow the steps below:
1. Select your equipment type from the guide below.
2. Use the Key Device Selection Criteria (time-to-open, surface temperature) to determine best suitability for your application.
3. Use Agency Specification / Selection Guide on the next page to select a specific part number for each application based on the agency requirements.
Figure FT1 - Thermal Derating Curve (Normalized) for FT600 Devices
70
80
90
100
110
120
130
-70 -50 -30 -10 10 30 50 70 90 110 130
% of Current Rating
Ambient Temperature °C
Protection Application Guide for Telecommunications and Networking Devices
Family Product Lightning Power Cross
FT600 FT600-0500 TIA-968-A (formerly FCC Part 68) - Type A & B UL60950, 3rd Ed. – 600VAC, 40A
FT600-1250 Telcordia GR-1089 – Level 1 and 2 Telcordia GR-1089 – 600 VAC, 40A
FT600-2000 TIA-968-A UL60950
Use the guide below to select FT600 devices appropriate for use in your application. The following pages contain specifications for part numbers
recommended below. FT600 devices enable telecommunication equipment to meet the applicable protection requirements of these industry
specifications. Refer to individual agency specifications for test procedures and circuit schematics. Users should independently evaluate the suitability
of, and test each product for their application.
Note: FT600-1250 and FT600-2000 are designed to assist equipment in complying with Telcordia GR-1089 specifications. In-circuit testing is strongly recommended.
The FT600-0500, FT600-1250 and FT600-2000 are designed to meet the UL60950 Power Cross and FCC TIA-968-A 68 lightning surge requirements. Note that Type A tests allow for an overcurrent protection
component to fuse open during the surge.
Agency Specification/Selection Guide for FT600 Devices
Part Ampere Rating Voltage Rating Typical Resistance Typical I2t
Number (A)(
V)(
Ω)(
A2S)*
FT600-0500 0.50 250 0.5 1
FT600-1250 1.25 250 0.1 16
FT600-2000 2.00 250 0.05 18
The FT600-xxxx devices are designed to carry 100% of rated current for 4 hours minimum and 250% of rated current for 1 second minimum, 120 seconds maximum.
Resistance measured at 10% of rated current.
*I2t is calculated at 10 ms or less.
Interrupt Voltage and Current Ratings for FT600 Devices
Telecom Fuses
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B
AC
Figure FT2 - Product Dimensions
Figure FT2 - Dimension Figures for FT600 Devices
Dimension
ABC
Part Number Min. Max. Min. Max. Min. Max. Figure
FT600-0500 — 10.5 — 3.4 — 3.4 FT2
(0.413) (0.133) (0.133)
FT600-1250 — 10.5 — 3.4 — 3.4 FT2
(0.413) (0.133) (0.133)
FT600-2000 — 10.5 — 3.4 — 3.4 FT2
(0.413) (0.133) (0.133)
Table FT1 - Dimensions for FT600 Devices in Millimeters (Inches)
Figure FT3 - Typical Time-to-open Characteristics (at 20°C) for FT600 Devices
FT600
A = FT600-0500
B = FT600-1250
C = FT600-2000
Figure FT3
TIME IN SECONDS
CURRENT IN AMPERES
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0.1
0.001
0.01
0.1
1
10
100
1 10 100 1000
ABC
.500A
1.25A
2A
Table FT2 - Physical Characteristics and Environmental Specifications for FT600 Devices*
Part Number Bag Quantity Tape & Reel Quantity Standard Package Part Marking Agency Recognition
FT600-0500-2 — 2,500 10,000 500 UL, CSA
FT600-1250-2 — 2,500 10,000 1250 UL, CSA
FT600-2000-2 — 2,500 10,000 2000 UL, CSA
Notes: The -2 designates tape and reel, the package style for this product.
Preheating
50
100
150
200
250
300
0
10 to 20
Temperature (°C)
Soldering Cooling
120
30 to 90
Time(s)
Solder Reflow:
• Recommended reflow methods: IR, vapor phase oven,
hot air oven
• Devices can be cleaned using standard industry methods
and solvents
Rework:
• If a device is removed from the board, it should be discarded
and replaced by a new device
Figure FT5
Device A B C D Figures for Dimensions
FT600-0500 12.6 4.0 3.7 5.2 4
(0.496) (0.157) (0.145) 0.204
FT600-1250 12.6 4.0 3.7 5.2 4
(0.496) (0.157) (0.145) 0.204
FT600-2000 12.6 4.0 3.7 5.2 4
(0.496) (0.157) (0.145) 0.204 A
DC
B
Figure FT4
FT600
Physical Characteristics
Terminal material Silver-plated brass*
Body material Ceramic
Termination solderability Per IEC-60127-4
*FT600 devices use high Pb content solder for internal construction. They are RoHS compliant.
Environmental Specifications
Test Conditions
Solder heat withstand Per MIL-STD-202, Method 210, Test Condition J
Solvent resistance Per MIL-STD-202F, Method 215J
Storage temperature -40/+85°C
Storage humidity Per MIL-STD-202F, Method 106F
* FT600 devices use high Pb content solder for internal construction. They are RoHS compliant.
Table FT3 - Packaging and Marking Information for FT600 Devices
Table FT4 - Recommended Pad Layouts for FT600 Devices in millimeters (inches) Nominal
Solder Reflow and Rework Recommendations for FT600 Devices
Telecom Fuses
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Part Numbering System for FT600 Devices
WARNING:
All information, including illustrations, is believed to be reliable. Users, however, should independently evaluate the suitability of
each product for their application. Tyco Electronics Corporation makes no warranties as to the accuracy or completeness of the
information, and disclaims any liability regarding its use. Tyco Electronics’ only obligations are those in the Company’s Standard
Terms and Conditions of Sale for this product, and in no case will Tyco Electronics be liable for any incidental, indirect, or consequential
damages arising from the sale, resale, use, or misuse of the product. Specifications are subject to change without notice. In addition,
Tyco Electronics reserves the right to make changes without notification to Buyer—to materials or processing that do not affect
compliance with any applicable specification.
Packaging
-2 :Tape & reel
FT -1250 -2600
Current in Amperes
1250=1.25
0500=0.500
2000=2.00
Voltage Rating
Product Family
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