Dell S6000 unsupported module type

Hello,

I have multiple Dell S6000 switchs that are giving me this error when I start it up

00:00:23: %STKUNIT1-M:CP %CHMGR-5-PEM_INSERTED: Power entry module 2 of unit 1 is inserted
00:00:23: %STKUNIT1-M:CP %CHMGR-1-PEM_UNSUPPORTED_TYPE: Major Alarm:Power entry module 2 of unit 1 is of unsupported type

Also the Power LED light keeps flashing a yellow light.

I have switched out the power supplies with another pair that I knew for sure were good but the same problem occurs. I was just wondering if anyone knew what this meant, or what i can do to fix it.  I'm pretty knew to this stuff so any feedback would be awesome.