Looking with interest at the differing views of inrush current of LED drivers.


I personally think it depends on whether the manufacturer has addressed the issue. Someone mentioned a particular make of driver having a high inrush current - well, some of their switched mode power supplies (SMPSUs) have the same problem.


But it's not the same with other manufacturers.


I'm sure that davezawadi will confirm that inrush current is something the driver manufacturer could have largely addressed for a few pence with a varistor inrush-current limiter, or either zero-voltage or zero-current switching for startup (dependent on the swtiching transistor arrangement in a switched-mode converter).


If a varistor is to be used, the truth of that is a little more complicated from a driver manufacturer's perspective, because the load attached to the driver or SMPSU needs to be known, so that you can calculate the required power dissipation and resistance range of the varistor.


Some of these drivers are probably sold as a universal component, perhaps with either full specifications, if not instructions of how to integrate them into a final product or system (and I would guess, from previous experience, the manufacturer stated previously in this thread would be in the bracket of providing full specs as their products have a very wide range of uses). If an LED luminaire manufacturer just packages the universal product without considerations such as inrush, and omits inrush limiting up-front, then you might have problems.


Similarly, if you purchase your own drivers separately to luminaires, it's something to check for, and address by adding inrush current limiting if you need to.


 

Looking with interest at the differing views of inrush current of LED drivers.


I personally think it depends on whether the manufacturer has addressed the issue. Someone mentioned a particular make of driver having a high inrush current - well, some of their switched mode power supplies (SMPSUs) have the same problem.


But it's not the same with other manufacturers.


I'm sure that davezawadi will confirm that inrush current is something the driver manufacturer could have largely addressed for a few pence with a varistor inrush-current limiter, or either zero-voltage or zero-current switching for startup (dependent on the swtiching transistor arrangement in a switched-mode converter).


If a varistor is to be used, the truth of that is a little more complicated from a driver manufacturer's perspective, because the load attached to the driver or SMPSU needs to be known, so that you can calculate the required power dissipation and resistance range of the varistor.


Some of these drivers are probably sold as a universal component, perhaps with either full specifications, if not instructions of how to integrate them into a final product or system (and I would guess, from previous experience, the manufacturer stated previously in this thread would be in the bracket of providing full specs as their products have a very wide range of uses). If an LED luminaire manufacturer just packages the universal product without considerations such as inrush, and omits inrush limiting up-front, then you might have problems.


Similarly, if you purchase your own drivers separately to luminaires, it's something to check for, and address by adding inrush current limiting if you need to.