State Diagram and State Transitions

State Diagram

When the product is powered on and when an operating mode is started, the product goes through a number of operating states.

The state diagram (state machine) shows the relationships between the operating states and the state transitions.

The operating states are internally monitored and influenced by monitoring functions.

Operating States

Operating state	Description
1 Start	Electronics are initialized
2 Not Ready To Switch On	The power stage is not ready to switch on
3 Switch On Disabled	Impossible to enable the power stage
4 Ready To Switch On	The power stage is ready to switch on.
5 Switched On	Power stage is switched on
6 Operation Enabled	Power stage is enabled Selected operating mode is active
7 Quick Stop Active	"Quick Stop" is being executed
8 Fault Reaction Active	Error response is active
9 Fault	Error response terminated Power stage is disabled

Error Class

The errors are classified according to the following error classes:

Error class	State transition	Error response	Resetting an error message
0	-	No interruption of the movement	Function "Fault Reset"
1	T11	Stop movement with "Quick Stop"	Function "Fault Reset"
2	T13, T14	Stop movement with "Quick Stop" and disable the power stage when the motor has come to a standstill	Function "Fault Reset"
3	T13, T14	Disable the power stage immediately without stopping the movement first	Function "Fault Reset"
4	T13, T14	Disable the power stage immediately without stopping the movement first	Power cycle

Error Response

The state transition T13 (error class 2, 3 or 4) initiates an error response as soon as an internal occurrence signals an error to which the device must react.

Error class	Response
2	Movement is stopped with "Quick Stop" Holding brake is applied Power stage is disabled
3, 4 or Safety function STO	Power stage is immediately disabled

Error class

Response

Movement is stopped with "Quick Stop"

Holding brake is applied

Power stage is disabled

3, 4 or Safety function STO

Power stage is immediately disabled

An error can be triggered by a temperature sensor, for example. The drive cancels the movement and triggers an error response. Subsequently, the operating state changes to 9 Fault.

Resetting an Error Message

A "Fault Reset" resets an error message.

In the event of a "Quick Stop" triggered by a detected error of class 1 (operating state 7 Quick Stop Active), a "Fault Reset" causes a direct transition to operating state 6 Operation Enabled.

State Transitions

State transitions are triggered by an input signal, a fieldbus command or as a response to a monitoring function.

State transition	Operating state	Condition / event⁽¹⁾	Response
T0	1-> 2	oDevice electronics successfully initialized
T1	2-> 3	oParameter successfully initialized
T2	3 -> 4	oNo undervoltage and Encoder successfully checked and Actual velocity: <1000 RPM and STO signals = +24V
T3	4 -> 5	oRequest for enabling the power stage
T4	5 -> 6	oRequest for ‘Drive ON’	Power stage is enabled. User parameters are checked. Holding brake is released (if available).
T7	4 -> 3	oUndervoltage oSTO signals = 0V oActual velocity: >1000 RPM (for example by external driving force)	-
T9	6 -> 3	oRequest for disabling the power stage
T10	5 -> 3	oRequest for disabling the power stage
T11	6 -> 7	oError of error class 1	Movement is canceled with "Quick Stop".
T12	7 -> 3	oRequest for disabling the power stage	Power stage is disabled immediately, even if "Quick Stop" is still active.
T13	x -> 8	oError of error classes 2, 3 or 4	Error response is carried out, see "Error Response".
T14	8 -> 9	oError response terminated (error class 2) oError of error classes 3 or 4
T15	9 -> 3	oFunction: "Fault Reset"	Error is reset (cause of error must have been corrected).
T16	7 -> 6	oFunction: "Fault Reset"	In the event of a "Quick Stop" triggered by a detected error of class 1, a "Fault Reset" causes a direct transition to the operating state 6 Operation Enabled.
(1) In order to trigger a state transition it is sufficient if one condition is met