First check to see if you have a warranty. a 3n1 will void any warranty you have on any the compressor... If it a Tecumseh compressor 134a this will mostly be a temporary fix.. 2 weeks to 2 months before the stater winding burn up.
The energy efficiency embraco compressor EM, F,EG, NE prefix will not last much longer either.
AC compressor can take the extra amperage that the hard start will sent to the start windings with a hard start.
VCC or Variable capacity Compressor will have three pins just like a AC compressor but will not have a relay it will have a AC/DC inverter. a gray box next to the compressor.
With today's compressors the 3n1 will be a temporary repair..if you need a relay use a factory relay . if it will not start it is time for a new compressor.