The document summarizes changes made to a cooler vent fan electrical system. It notes that the original electrical team had removed parallel conductors from the disconnect to the fuses, limiting the system's capacity. By adding back the parallel conductors and increasing the size of the fuses, the updated configuration resolved issues with fuse failure and reduced heat levels around the fuses. Thermography images before and after the changes are included for comparison.

1. Cooler Vent Fan
February 25th 2023
CE101-M51475
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2. Changes Made
1 Added parallel
conductors from
disconnect to fuses.
2 Increased the size of the
fuses from JJS-500 to
KTU-900
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3. Leading up to the fix
While investigating the drive we interviewed the electrical
team and determined that changes had been made a year
prior. Winn-Marrion was the company that made the
changes, they removed parallel conductors from the
disconnect to the fuses. This was the only change we were
aware of at the time. Since the changes were made by
Winn-Marrion we had tried several different sized fuses to
resolve the issue, none worked.
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4. Before and After
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5. Load Side of Disconnect
This is a picture of before we made the changes, we have 3 conductors 250
MCM Welding Cable which are rated at 405 Amps in this configuration. We
did some thermography imaging as well and did find some heat around the
fuses, but nothing extreme.
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6. ACS800 ABB Drive
The drive is rated at 670
FLA which is above the
capacity of the 3
conductors.
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7. Once we added the parallel cables
and increased the fuse size we
saw a decrease in temperature
around the fuses and have not had
any fuse failure since.
After changing the
configuration
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8. Side by side comparison
• Before • After
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