15HP meat grinder

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jim dungar

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Saturn_Europa said:
BTW....... I tend to stay away from IEC rated starters. They have a shorter life then NEMA gear.
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For a large part, NEMA devices last longer than IEC ones because they are not sized the same.
For example: For a 5HP 480V general use motor, many people will choose a NEMA size 1 device because they do not like the life of a IEC 5HP option. The reality is the NEMA size 1 is rated for 27A while the IEC is rated for only 9A. Talk about comparing Apples to Oranges.

A UL Listed 27A IEC style device passes the life cycle tests as a NEMA size 1 does.
I sold my first IEC style device more than 30 years ago, I have come to the conclusion electricians do not like IEC but they have no problem going with Definite Purpose devices. Small size, limited life, and cheap components must not really be the issue.

As far as automatically up sizing the overload - Please don't. Instead, read the instructions that need to be followed (some manufacturers included a SF adjustment when they came up with their sizing table).
 
iwire

iwire

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jim dungar said:
I have come to the conclusion electricians do not like IEC but they have no problem going with Definite Purpose devices. Small size, limited life, and cheap components must not really be the issue.
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The conclusion I have come to is that I have replaced many more IEC contactors that self destructed than either NEMA or DP devices. Where the IEC contactors misapplied? Maybe but I don't design the equipment I only service it.
 
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GoldDigger

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Jraef said:
Read The <Factory> Manual :angel:
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Some say Read The <Fine> Manual instead.

They tell the story of the avionics tech on an aircraft carrier whose primary job was to pull faulted modules and do the bench repair later.
One shelf, of the hopelessly unrepairable, was labelled NFG.
During an inspection by a female officer, he was asked what the label meant.
He coolly replied "Non Functioning Gear, ma'am."
 
kwired

kwired

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Saturn_Europa said:
If the OP uses a NEMA starter with bi-metallic OL s. Shouldn't he take the FLA and multiple it by the service factor of the motor (usually 1.15) to size the OLs.

BTW....... I tend to stay away from IEC rated starters. They have a shorter life then NEMA gear.
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With NEMA starters with thermal overload elements, the proper way to size the elements is to use the proper selection table published by the manufacturer. For single enclosed starters the applicable table often is a label attached to the enclosure somewhere but you can also find selection tables in their product catalog. To find the correct table you need starter series information, number of thermal overloads that will be used, and other information on the enclosure as well as whether or not there is other heat producing components in the enclosure.

You select an element based on motor nameplate full load. The 125% that NEC allows is already factored into the selection table. If you have other then a 1.15 or 1.25 service factor - the instructions may tell you to multiply motor nameplate current by .90 and use that value for selecting the proper element.
 
kwired

kwired

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NEMA vs IEC starters? If this machine gets used daily, NEMA is probably the way to go. If it gets used only occasionally IEC might be worth consideration. If it gets used just a couple weeks of the year then sits for another year, IEC consideration rises even more.
 
MNSparky

MNSparky

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Ok, got word back from the customer. The grinder has an additional attachment that isn't in the pic that bolts onto the top of the hopper to make it really deep. Basically, you would have to stick your arm in there up to your armpit to touch the screws. It gets loaded by dumping buckets into it. I expressed my concerns about liability and he is willing to sign a liability release.

They use it to grind up fish to make fertilizer, nothing food related.
 
MNSparky

MNSparky

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Minneapolis, MN
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Electrical Contractor - 2023 NEC
Jraef said:
Glad to see you got some clarity on those issues.

So are you good on the electrical aspect now?
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Yes. I didn't hear any arguements against my calculations, outside of the heaters, so I must have done them correctly. Thank you all for the assistance.
 
kwired

kwired

Electron manager
Location
NE Nebraska
MNSparky said:
Yes. I didn't hear any arguements against my calculations, outside of the heaters, so I must have done them correctly. Thank you all for the assistance.
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Your 60 amp breaker may not hold for startup. 42 x 2.5 = 105 not 60.

My Square D motor slide calculator says to use an 80 amp breaker or 60 amp time delay fuses.
 
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