Internal relay M

[S.amine 0]

Why we use internal relay M in mistubishi plc. 

[panic mode 246]

it is internal memory, meant for bit-wise access... other types also exist like L, B. D etc.

they all can be used store information and keep track of things. 

unlike inputs and outputs they are not exposed to external world.

[WattUp 34]

Little more detail in case you are new to the Mits PLCs

M are basic internal relay bits. 

D are basic internal Words

L are Latched internal relays (their state remains through power cycles)

X/Y Obviously inputs & outputs

T are timers

C are counters

Z are pointer modifiers i.e. [MOV K150 D100Z1] would move value of 150 to D100+(Value of Z1), so if Z1 = 10, D110 would