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US3J & US6J
UltraSafe™ Class J Fuse Holders
FUSE BLOCKS & HOLDERS
ULTRASAFE™ MODULAR FUSE HOLDERS
FOR CLASS J FUSES
Mersen UltraSafe Modular 600 Volt Fuse Holders for Class J fuses
introduce a new level of safety and ease for installing or replacing
Class J fuses. UltraSafe holders qualify as “finger-safe” to an IP20
grade of protection under IEC standards. The US3J accommodates
30A Class J or 22 x 58 mm French Ferrule* fuses. The US6J is for
60A Class J fuses. UltraSafe holders are available in compact 1, 2,
or 3 pole units, with or without blown-fuse indicators in each pole.
Multi-pole units can also be made up in the field by using the multiple-
pole Assembly Kits. All units have provisions for locking in the open
position for safety during fuse changeouts or equipment servicing.
US3J and US6J holders can be snap-mounted to 35 mm DIN-rail and
they have a unique latch which will stay open to allow re-positioning
of the holder in the future. UltraSafe body material is tough and
durable polyamide.
*Holder not UL listed when installed with French Ferrule fuses.
RECOMMENDED FUSE USAGE:
US3J, US6J use with AJT, A4J, HSJ
RATINGS:
• Volts: 600VAC/DC
• Amps: US3J - 30A Maximum,
US6J - 60A Maximum
• SCCR: 200kA
Min. voltage to operate indicator light:
90VAC, 115VDC [Less than 0.7 mA leakage
current at 600V]
HIGHLIGHTS
• Finger-safe IP20
protection
• Optional indicator lights
• DIN-rail mount
• Compact footprint
• Quick, easy fuse change
APPLICATIONS:
• 600 volt motors,
transformers, lighting, heating,
control circuits, general loads
• Non-load disconnect
APPROVALS:
• UL Listed, guide IZLT File
E52283
• CSA Certified C22.2, class
6225 01, File 32169
• IEC certified 60269-1,
60947-3
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FUSE BLOCKS
& HOLDERS
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US3J & US6J
UltraSafeTM Class J Fuse Holders
Catalog No.
W/O Indicator
Catalog No.
W/ Indicator Description Fuse Type Voltage Rating Ampere
Rating
No. of
Poles Certications
AC DC
US3J1 US3J1I 1-Pole 30A Class J UltraSafe Fuse Holder
Class J 600V 600V
30A
1
UL Listed
CSA Approved
IEC Certied
US3J2 US3J2I 2-Pole 30A Class J UltraSafe Fuse Holder 2
US3J3 US3J3I 3-Pole 30A Class J UltraSafe Fuse Holder 3
US6J1 US6J1I 1-Pole 60A Class J UltraSafe Fuse Holder
60A
1
US6J2 US6J2I 2-Pole 60A Class J UltraSafe Fuse Holder 2
US6J3 US6J3I 3-Pole 60A Class J UltraSafe Fuse Holder 3
CATALOG NUMBERS
DIMENSIONS
ADDITIONAL SPECIFICATIONS:
Terminal screws: Phillips/slot head
Suggested screw torque: 30A - 35 in-lbs.
60A - 45 in-lbs.
Connector type: Pressure plate
Wire range: #2 to #14 (solid/stranded Cu)
Load-break disconnect: No
Dimension US3J US6J
mm In mm In
A 32.5 1.28 40 1.57
B65 2.56 80 3.15
C97. 5 3.84 120 4.72
E114 4.49 122 4.80
F 3 0.12 30.12
G106 4.17 115 4.53
H 80 3.15 89 3.50
I 56 2.20 62 2.44
J 6.5 0.26 6.5 0.26
CATALOG NUMBERS –
ACCESSORIES
Accessories Catalog No. Description
US3JN 1-Pole Neutral 30A Class J UltraSafe Fuse Holder
US3JPAK Pin Tie Assembly Kit, 6-Poles, for use with US3J
US6JN 1-Pole Neutral 60A Class J UltraSafe Fuse Holder
US6JPAK Pin Tie Assembly Kit, 6-Poles, for use with US6J