customer has 6 container type freezers. 5 freezers have a 25amp max for each freezer and 1 freezer has a 12.6amp for currebt but a 82amp inrush current on label. the customer wants us to install 6-60a fused disconnects for each freezer with 60amp fuses. Customer was told my container company that these would work. I kinda want to install 30amp fuses in disconnects and what do you think about the1 freezer with 12.6amp current and 82a inrush current.I put an amprobe on it but never saw it get over 30amps. would the 30a disconnect work on that particular freezer? I might be leaving something out. I am trying to post before the evening ends.
AC max draw 25a
- Thread starter mannyb
- Start date
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texie
Senior Member
- Location
- Fort Collins, Colorado
- Occupation
- Electrician, Contractor, Inspector
If these are packaged units with hermetic compressors and listed they should have a data plate indicating the minimum circuit ampacity and the max OCPD.
pjones
Member
- Location
- Vancouver Canada BC
Like Texie said. Put the max size disconnect allowed as per the name plate on the unit. Size the wires to conform with the name plate as well. Just because the units were operating at 30 amps when you saw it doesn’t mean it won’t draw higher when the electric defrost turns on, compressor has to pull down a hot box, second stage cooling kicks in, or some other function occurs that you didn’t plan for.
If it’s operating at 30 amps and you put a 30 amp breaker on it then it will certainly pop the breaker, usually at the most inconvenient time.
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The name plate only gives the 25a max. It also gives a 5995 watts @ 0*Farh 10,236 watts @ 35*Farh these things are from Singapore. Carrier brand. I am not sure what size breaker to install 30a or ?? The amp draw while running is 12 to 13 amps
I only had one unit that mentions the 82a at start up. The other 5 only mention the 25a max andi t also gives a 5995 watts @ 0*Farh 10,236 watts @ 35*Farh these things are from Singapore. Carrier brand. I am not sure what size breaker to install 30a or ?? The amp draw while running is 12 to 13 amps.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
25a max is 25a max.
pjones
Member
- Location
- Vancouver Canada BC
From what you describe, the watts rated at different temperatures sounds like it’s referring to the specified cooling capacities (similar to BTUH but calculated in watts instead) irrelevant for your task at hand. Can you post a picture of the data tag? I don’t typically see a rating for a “start-up” amperage.
The way I read your first post is that you actually measured 25 amps on the units, I didn’t realize the data plate specified 25amps max. Is that 25A listed next to a “max fuse size disconnect” identifier ( if it is then follow Larry’s advice), or is it next to a “compressor” identifier?
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- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
Let's see.......the sign says max speed 45 MPH, should I go 65 or 70?
If you have a "max" on the plate, why would you have to ask what size to use?
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