Operating Modes Of The Device Em12D-Tmb; Operating Mode: System Start; Operating Mode: Critical Failure; Operating Mode: Non-Critical Failure - E-T-A ControlPlex EM12D-TMB Instruction Manual

Table of Contents

4. OPERATING MODES OF THE DEVICE EM12D-TMB

The Modbus controller is initialised by applying the supply voltage. The device will carry out implemented pro-

gramme memory tests and self test routines. During this time a communication via the interfaces is not possible.

If a failure is detected during the self test routines, the Modbus controller will change into operating mode "critical

failure". In the event of a critical failure, the device will also change into this operating mode. This operating mode

can only be discontinued by way of re-starting the device and it prevents the data exchange via the interfaces. If

the Modbus controller is in this operating mode, no communication is possible with the superordinate control unit.

The electronic circuit protectors cannot be controlled by it and remain OFF.

If there are no valid or invalid configuration data available in the Modbus controller, it will change into this operating

mode. This operating mode will be left upon receipt of the correct module and slot parameters and configuration

data. The circuit protectors remain OFF.

If no connection to the superordinate control unit is recognised after the supply voltage was applied, the module will

change into the operating mode "independent operation". The circuit protectors will adopt the condition specified by

the configuration. If there is a connection between the Modbus controller and the superordinate control unit and

there is no critical failure, the operating mode "independent operation" will be quitted. Should the connection be-

tween the Modbus controller and the superordinate control unit be interrupted during operation, the Modbus con-

troller will automatically change into the operating mode "independent operation".

Should the connection between the Modbus controller and the superordinate control unit be interrupted and the

non-cyclical parameter "UNFREEZE" be set, all circuit protectors will be switched off before changing into the oper-

ating mode "independent operation".

Should the connection between the Modbus controller and the superordinate control unit be interrupted and the

non-cyclical parameter "FREEZE" be set, the condition of the circuit protectors will remain unchanged before

changing into the operating mode "independent operation".

By means of the non-cyclical parameter, the behaviour of the Modbus controller can be defined in the event of an

interruption of the communication to the superordinate control unit.

Either the condition of the circuit protector is frozen (FREEZE) or all circuit protectors are switched off (UN-

FREEZE).

Should the connection between the Modbus controller and the superordinate control unit be restored after a previ-

ous interruption, the operating mode "independent operation" will be quitted.

Table of Contents