AC Disconnect Box

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SKSolar

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I am planning to install a grid-tie solar PV system for the first time after receiving training from college and Enphase . I need a 40A AC Disconnect Box between the AC Combiner Box to the 40A breaker at the 200A service panel.
I saw people using the fused 60A Eaton DG222NRB (with 40A fuse used) which cost about $145. I don't understand why some models costs only $20 or so (even with the same brand) which (I maybe wrong) believe they accomplished the same thing. Can someone comment on the differences that added extra dollars? What I should look for in the AC Disconnect?
I have 4 # 8 AWG (L1, L2, N, G) in the box. Thanks
 
SKSolar said:
I am planning to install a grid-tie solar PV system for the first time after receiving training from college and Enphase . I need a 40A AC Disconnect Box between the AC Combiner Box to the 40A breaker at the 200A service panel.
I saw people using the fused 60A Eaton DG222NRB (with 40A fuse used) which cost about $145. I don't understand why some models costs only $20 or so (even with the same brand) which (I maybe wrong) believe they accomplished the same thing. Can someone comment on the differences that added extra dollars? What I should look for in the AC Disconnect?
I have 4 # 8 AWG (L1, L2, N, G) in the box. Thanks
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We were talking about this recently in a thread, specifically fused disconnects vs a small panelboard or circuit breaker enclosure. I would use the latter in your case, they're like 30 bucks.
 
SKSolar said:
... . I need a 40A AC Disconnect Box between the AC Combiner Box to the 40A breaker at the 200A service panel.
Click to expand...
Why, exactly? Utility requires a bladed disconnect, or some other reason?

If a bladed disconnect is required, I'd use an unfused disconnect since it's cheaper and simpler. You already have overcurrent protection at the breaker in the service panel so a fused disco and fuses are a waste of money.

If a bladed disconnect is not required, then a small panelboard or circuit breaker enclosure like electrofelon mentioned also works.
 
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