Power-ON problem of LT4275A - LTPoE++ with DC1815A-D-ND with load above 30W


I am working with power over ethernet and using PD LT4275A with DC1815A pse. The circuit seems to be working properly at least till 70W. But am facing a problem at startup.If the Power demand at the start of board is higher than around 10-12W, the power is cutting off(it need a power reset for normal operation eventhough load reduced to zero) .But if we are giving load after power-on of IC , the board is capable of drawing power till 70W(maybe 90W). Please let me know the factors affecting problems at the start. Am working with PoE-PD lighting.So if i connect led (say led of rating 1A), it would switch on . But if I switch on without power and connect load afterwards, then it is working..

Can i get some clues to sort out the issues?

Both PSE and PD am using is of rating LTPoE++(power-90W).