Internal overload protection

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nizak

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How would one go about finding if there is internal overload protection provided in a 3 phase refrigeration unit?

I got info from a company that installs commercial freezer/ coolers and they say I need to supply a 35 amp MOPD) 230V 3 phase circuit and a disconnect.

Breaker is HACR type.
 
retirede said:
Have them send you a picture of the nameplate. It should contain all the info required.
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I did. It gives minimum circuit ampacity, maximum over current protection device, voltage, and phase.

Says nothing about fuses or requirement of fuses.
 
nizak said:
I did. It gives minimum circuit ampacity, maximum over current protection device, voltage, and phase.

Says nothing about fuses or requirement of fuses.
Click to expand...
OK, so you have the info you need. Just size the conductors to the MCA and use the max value for the OCPD. If the label just says max OCPD and does not mention fuses, then either fuses or breaker is OK. FYI, all breakers today are rated HACR by default as part of the listing and do not have to be marked as such. If the label said "max fuse" then you would be obligated to use fuses. Keep in mind that the OCPD and the conductor ampacity do not have to match as the label values tell you it is listed as HVAC equipment and has built-in overload protection.
 
texie said:
OK, so you have the info you need. Just size the conductors to the MCA and use the max value for the OCPD. If the label just says max OCPD and does not mention fuses, then either fuses or breaker is OK. FYI, all breakers today are rated HACR by default as part of the listing and do not have to be marked as such. If the label said "max fuse" then you would be obligated to use fuses. Keep in mind that the OCPD and the conductor ampacity do not have to match as the label values tell you it is listed as HVAC equipment and has built-in overload protection.
Click to expand...
Thank you for the informative reply.
 
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