FX Series Programmable Controllers

Devices in Detail 4

4.4State Relays

FX1S

FX1N

FX2N

FX2NC

Device Mnemonic: S

Purpose: Internal programmable controller status flag

Alias: State (coil/ relay/ contact/ flag)

S (coil/ relay/ contact /flag)

STL step (coil/ relay/ contact /flag)

Annunciator flag

Available forms: NO () and NC contacts and output coils () (see example device usage for references)

Devices numbered in: Decimal, i.e. S0 to S9, S10 to S19

Further uses: General stable state - state relays - see page 4-6 Battery backed/ latched state relays - see page 4-7 STL step relays - see page 4-8

Annunciator flags - see page 4-9

Example device usage:

X0

S20

X1

S20

2

1

4.4.1General Stable State - State Relays

A number of state relays are used in the PLC. The coils of these relays are driven by device contacts in the PLC in the same manner that the output relays are driven in the program.

All state relays have a number of electronic NO and NC contacts which can be used by the PLC as required. Note that these contacts cannot directly drive an external load. Only output relays can be used to do this.

Available devices:

Please see the information point on page 4-7 ‘Battery backed/ latched state relays’, or see the relevant tables for the selected PLC in chapter 8.

4-6

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Mitsubishi Electronics FX1S manual Device Mnemonic S, General Stable State State Relays