Moeller - Fuses for circuits in North America - Selection and application of fuses suitable for circuits (feeder and branch circuits) in North America.

Selection and application of fuses suitable for circuits (feeder and branch circuits) in North America.


Type or design in:		Standards UL, CSA	Fuse characteristics	SCCR	Typical values in A	Fields of application		Notes
USA	Canada	Standards UL, CSA	Fuse characteristics	SCCR	Typical values in A	Fields of application		Notes

Class H, "Code"	Class H, No. 59 "Code"	UL 248-6/7, C22.2 248-6/7	fast	10 kA, 250 VAC	0…600	Primarily domestic		Types H, K and No. 59 “Code” fit the same bases and are therefore interchangeable. There is therefore a risk that they may be incorrectly used! See also note on K.
Class H, "Code"	Class H, No. 59 "Code"	UL 248-6/7, C22.2 248-6/7	fast	10 kA, 600 VAC	0…600	Primarily domestic
Class CC	Class CC	UL 248-4, C22.2 248-4	fast slow	200 kA, 600 VAC	0.5…30	fast: Protection from resistive and inductive loads. Circuits for heating, lighting, feeders and branches for mixed loads.	slow: Protection from inductive and highly inductive loads. Circuits for motors, transformers, lighting etc.	Extremely compact design! Current-limiting to UL/CSA!
Class G	Class G	UL 248-5, C22.2 248-5	fast slow	100 kA, 480 VAC	21…60			Compact design. Current-limiting to UL/CSA! All other fuse types do not fit into bases.
Class G	Class G	UL 248-5, C22.2 248-5	fast slow	100 kA, 600 VAC	0.5…20
Class J	Class J HRCI-J	UL 248-8, C22.2 248-8	fast slow	200 kA, 600 VAC	1…600			Compact design. Current-limiting to UL/CSA! All other fuse types do not fit into bases.
Class K K1, K5	Class K K1, K5	UL 248-9, C22.2 248-9	fast slow	50 kA/100 kA/ 200 kA, 600VAC	0…600			Not current-limiting to UL/CSA! In the USA, the K types are therefore being increasingly replaced by the RK types.
Class L	Class L	UL 248-10, C22.2 248-10	fast slow	200 kA, 600 VAC	601…6000			Current-limiting to UL/CSA! All other fuse types do not fit into bases.
Class R RK1, RK5	Class R HRCI-R RK1, RK5	UL 248-12, C22.2 248-12	fast slow	50 kA/100 kA/ 200 kA, 600VAC	0…600			Current-limiting to UL/CSA! Types RK1, RK5 and HRCI-R fit the same bases. All other fuse types do not fit into these bases. RK1 fuses have lower let-through values than RK5.
Class T	Class T	UL 248-15, C22.2 248-15	fast	200 kA, 300 VAC 200 kA, 600 VAC	0…1200		_	Extremely compact design! Current-limiting to UL/CSA! All other fuse types do not fit into bases.

The characteristics data and the assigned applications are a rough overview only.

The practice, it is always advisable to find out both this information and the required fusel type from the North American end customer.

The NA fuse types are largely tested and suitable for DC circuits in accordance with UL and CSA.