When a safety switch is installed adjacent to the motor, the maximum size DETD fuses permitted are ___ A.

When a safety switch is installed adjacent to the motor, the maximum size DETD fuses permitted are ___ A.

• A. 90
• B. 125
• C. 80
• D. 150

Answer: (A)

When a safety switch is placed right next to the motor, the fuse rating in that disconnect is limited to a specific upper limit to ensure proper protection coordination with the motor and its wiring. For this arrangement, the largest DETD fuse size you can use is 90 A. Ratings larger than that (like 125 A or 150 A) aren’t permitted because they would exceed the allowed maximum and could compromise motor protection. An 80 A fuse is allowed, but it’s smaller than the maximum, so 90 A is the correct choice as the largest permitted size.

When a safety switch is placed right next to the motor, the fuse rating in that disconnect is limited to a specific upper limit to ensure proper protection coordination with the motor and its wiring. For this arrangement, the largest DETD fuse size you can use is 90 A. Ratings larger than that (like 125 A or 150 A) aren’t permitted because they would exceed the allowed maximum and could compromise motor protection. An 80 A fuse is allowed, but it’s smaller than the maximum, so 90 A is the correct choice as the largest permitted size.