Wednesday, August 31, 2016

SSPA Power Supply - Larger Thermistors

I am swapping out the 1 Ohm Thermistors for some 10 Ohm's.  The 1 Ohm's seemed to only just barely dip the inrush.  I'm looking for something more dramatic.

So we'll see how this effects inrush.  These new ones are 18 amp 10 Ohm.  The 1 Ohm's were rated 30 amp.  

I went about this all wrong to start with.  And I'm learning as I go so please don't laugh too much. :-)  I've never used Thermistors before so this is mostly just so I can have some hands on real world exposure to using them.  

Truth is I don't really think I need this step start / soft start with this power supply.  But it certainly won't hurt anything, and it gives me a chance to learn something new that I'm sure I'll be able to use in the future.

Anyway 1 Ohm @30 Amp Thermistors only dropped inrush by about 1.5 amps @240 vac. 
I'd like to see total inrush really dropped by like 50% or more if I can.  Total inrush was 8.5 amp with the 1 Ohm's.  I'd like to see that cut in half or even more.  

But gut says this still isn't enough to do that...but we'll see.  Here are some pix.  

The 10 Ohm thermisors are the large ones in the photo's below.