Is it a T100MD2424+ PLC? If so, you need to connect a 24V power to the MCR input terminal (the terminal between the 0V and Output 7) so that the output will receive power. This unique capability only aplies to T100MD2424+ which allows user to shut off most of the PLC outputs via external control (MCR input) without turning off power to the PLC.
However, not connecting the MCR input will not affect communication. If your PLC is not a T100MD2424+ and yet there is no status LED blink when power on, then please check the power supply to the PLC. Check if there is 24V across the power supply terminal. If you are powering it using 12V, make sure that the jumper J1 is put at the correct place.
If all else fail, then please contact sales@tri-plc.com to arrange for replacemnt unit to be shipped to you.