Have to use fused disconnect if the walk-in freezer compressor name plate state "Max. Fuse Size"?

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That label doesn't say a fuse is required.

It indicates Maximum Fuse size of 35 amps.

If the max fuse size is not needed, why would one be held to installing a fuse at all?

JAP>
 
jap said:
That label doesn't say a fuse is required.

It indicates Maximum Fuse size of 35 amps.

If the max fuse size is not needed, why would one be held to installing a fuse at all?

JAP>
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I was always taught that “Max fuse size” means a fuse is required.

If it said “Maximum OCPD”, would you think that no OCPD is required if you didn’t need the max?
 
retirede said:
I was always taught that “Max fuse size” means a fuse is required.

If it said “Maximum OCPD”, would you think that no OCPD is required if you didn’t need the max?
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The breaker feeding the disconnect takes care of the OCP part of it.

If you have a 30 amp breaker feeding the disconnect for the OP"s unit you wouldn't have met the max fuse size of 35 amps.

So why would a fuse be needed?

JAP>
 
infinity said:
That's what I had been taught too but where in the NEC does it say that?
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It gets down to 110.3(B) and the product standard for the equipment. The product standard requires that the type and maximum size of OCPD be on the nameplate. Where the type of OCPD shown on the nameplate is a fuse, you are only permitted to use a fuse.

I have not seen one with that marking in a long time. Typically that marking predates the HCAR breakers which have been around for at least 3 decades now. It has to do with the protection of equipment that has multiple motors, and standard breakers did not do a good job with that.

When the HCAR breakers first came out, the name plate marking would often say "fuse of HCAR breaker". Now most just say OCPD because all listed breakers are HCAR breakers.
 
don_resqcapt19 said:
It gets down to 110.3(B) and the product standard for the equipment. The product standard requires that the type and maximum size of OCPD be on the nameplate. Where the type of OCPD shown on the nameplate is a fuse, you are only permitted to use a fuse.

I have not seen one with that marking in a long time. Typically that marking predates the HCAR breakers which have been around for at least 3 decades now. It has to do with the protection of equipment that has multiple motors, and standard breakers did not do a good job with that.

When the HCAR breakers first came out, the name plate marking would often say "fuse of HCAR breaker". Now most just say OCPD because all listed breakers are HCAR breakers.
Click to expand...

I agree with others that mentioned more care needs to be put into the nameplates to indicate both the type and the max size.

JAP>
 
don_resqcapt19 said:
It gets down to 110.3(B) and the product standard for the equipment. The product standard requires that the type and maximum size of OCPD be on the nameplate. Where the type of OCPD shown on the nameplate is a fuse, you are only permitted to use a fuse.
Click to expand...
So this is a UL standard and has nothing to do with the NEC?
 
infinity said:
So this is a UL standard and has nothing to do with the NEC?
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Respectfully: With 110.3(b) involved, I don't think we can say it has "nothing to do with the NEC".
(110.3(b) is how I address the UL standard)
 
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