Packaged freezer unit - Breaker/Max Fuse Size

[maxwolf]

Hi All,

I need to buy a packaged freezer unit and have received a spec from Norlake with the following electrical data:
208-230V/60Hz/1P
Total system refrigeration amps = 11.4A
Total system defrost amps = 7.1A
Min. circuit amps = 14.2A
Max fuse size = 20A

We told Norlake that we have a 15A breaker available in the room that we want to put the unit (it’s indoor; Norlake model #CPX150DW). Please comment on any issues. We will be using a stepup transformer from 110/60/1 to 208-230/60/1.

Thanks for your help.

 

[davidbeach]

15A of 120V won’t begin to be enough. Any place that has 120V should also have either 208V or 240V, just use that directly.

 

[LionelHutz]

Did you forget that apparent power = Volts x Amps? To get 20A @ 240V would require 40A @120V.

 

[waross]

The maximum continuous load allowed on a 15 Amp breaker is 12 Amps.
I hope that that 15 Amp breaker is a two pole breaker.
Replace twp pole 15 Amp breaker with a 2 pole 20 Amp breaker.
If you have to ask this question, Hire an electrician.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[jraef]

If all you have is 120V at a 15A outlet, that is less than half of the size of circuit you need. Your Minimum Circuit Amps (load) is 14A at 208V, which translates to 24A at the 130V circuit. You need a 30A circuit breaker feeding 10ga wire for this(if you persist in using 120V).

Again, hire an electrician and have it done right. This is not a DIY situation (nor is this a DIY site).


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[waross]

If you have only a single pole 15 Amp breaker at 120 Volts, You will need a transformer to run the unit.
Hire an electrician.
If the breaker panel is full, the electrician may opt to change two existing 15 Amp breakers to a tandem breaker, or in some panels, half width breakers.
Then you will have the space to change a single pole 15 Amp breaker to a two pole 20 Amp breaker.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[HCBFlash]

So, you got your answer here already. I'll only go further to tell you, apparently somebody that has some responsibility for this project or facility, that you're seeing ranges of values instead of fixed figures, and there are firm reasons for that. If this unit is important and may have high failure costs including replacement costs, have your INDUSTRIAL electrician, or equipment supplier, tell you what overheating and overcurrent protection is integral (the "Maximum fuse size" rating sometimes indicates that there is none). If there is none, a "motor starter" may be the best protection for the unit, as it can be adjusted, or have elements installed to provide the best possible "trip curve" to prevent overheating or overload damage to the unit, as well as provide alarm contacts to signal any shutdown for those conditions.

I think most likely, however, is that the equipment supplier really wants this thing plugged in to a 230v, 20a 2w +g receptacle, with it's very own branch circuit.

.

(Me,,,wrong? ...aw, just fine-tuning my sarcasm!)