PLA print warping on heated bed
Several things I've done to stop warping when it occurred:


Use a wider brim.
If the brim isn't sticking, use a higher bed temperature for the first layer.
If the brim comes up only on one side or warping is only on one side, make sure the bed is level.  
Slowing down the print will keep you from having as long of a strand cooling down.  This will lower the contraction force and reduce warping.  
A hotter bed temperature will reduce the temperature difference between the extrusion and the bed, thus reducing the contraction force.  


200&nbsp;°C is a good temperature for getting PLA to stick.  I've tried lower extrusion temperatures to reduce the temperature difference between the extruder and the bed, but this decreases adhesion to the bed and is counterproductive.