LED 4 foot lamps

A manufacturing client is having issues with 5 rows of fixtures. 22 4 foot fixtures, 4 lamps across each, 5 rows.
He replaced all rows with LED lamps removing the ballasts. 277 volt. rows will not turn on unless a large current is running from a 480 volt machine .
We have checked voltage , 277 volt, added # 10 nuetrals to each circuit, checked all wire connections. no change to the behavior.
voltage is good at the beginning of each row but the row wont turn on.