AutoGen_8786121

How to connect PNP encoder for this SB 1223 DC/DC 24v223 DC/DC 24v(or 5v)? it doesn't have a 1M port to reference the V+/0V 

The documentation states that the 6ES7221-3BD30-0XB0 signal board is only NPN. 

AutoGen_8786121

 someone said that whether the SB 1221 DI receives a sink or source signal depends on the 1M port on your s7 1200 CPU, whether it is a sink or a source. which means if your s7 1200 CPU is sink, so will your SB 1221 DI, and vice versa. I need to know is this correct? i don't want to mess up my SB 1221 DI.

The onboard CPU inputs can be wired as sink or source -- that is true.
Even the system manual says so.
There is however no mention on changing the SB NPN <-> PNP.

The wiring of the CPU inputs to change the circuitry of the SB is not known to me. So.. you can do some testing for yourself or ask Siemens via the "Support Request" link.

To do the test yourself in a safe way:
1) Connect an NPN device to the SB.
2) Do not connect anything to the input of the CPU.
3) Power on. Load your test program. 
4) Test if the NPN device switches the input of the SB. Report the result.
5) Power off.
6) Connect the CPU inputs as PNP inputs with a PNP device.
7) Power on. Test onboard and SB inputs. Report the result.
8) Power off.
9) Connect the CPU inputs as NPN inputs & with a NPN device.
10) Power on. Test onboard and SB inputs. Report the result.
11) Make a conclusion if the PNP/NPN switching of the onboard inputs has an influence on the SB inputs.

So what are your findings.