I posted this information here before in relation to safety reset pushbutton colours, but it also contains some details on indicator colours according to EN 60204-1...
E-Stop manual reset button
There is also some additional information on the use of flashing frequencies to further enhance an indicator's ability to alert personnel to a particular condition.
To take your examples above -
keshik said:
...What are you using to indicate that the machine is running in automatic (normal) operation? What are you using to indicate the presence of a fault (for example, hydraulic oil overtemperature causing the machine to drop out of automatic)?
Under EN 60204-1, and as I detailed in that older post, these are the common indicator colours and their meaning -
Table 3: Colours of indicator lights and their meanings relating to the machine status
Colour: RED
Meaning: Emergency situation
Description: Dangerous condition
Operator action: Immediate action to respond to a dangerous condition (e.g. by pressing emergency stop)
Colour: YELLOW
Meaning: Abnormal condition
Description: Abnormal condition; anticipated critical condition
Operator action: Monitoring and/or intervention (e.g. by restoring the intended function)
Colour: GREEN
Meaning: Normal condition
Description: Normal condition
Operator action: Optional
Colour: BLUE
Meaning: Mandatory action
Description: Indication of a condition requiring operator intervention
Operator action: Mandatory action
Colour: WHITE
Meaning: Neutral
Description: Other conditions; may be used if there is uncertainty about the appropriateness of RED, YELLOW, GREEN or BLUE
Operator action: Monitor
To indicate a machine in the normal running condition I would use a GREEN indicator permanently ON. Example: Machine start sequence complete.
To indicate a machine in a general fault condition, or to indicate a specific fault condition, where the fault has stopped the machine, or the Operator is required to stop the machine, or the fault is holding off the machine, I would use a RED indicator permanently ON. Example: Hydraulic oil over-temperature condition.
To indicate an abnormal condition where the Operator's attention is required but the machine may continue to operate, or operation may be resumed, I would use a YELLOW indicator flashing - frequency f1 ratio: 1:1.5. Example: Hydraulic oil low level condition.
Note: for enhancing conditional annunciation, audible alarms can also play a role here, as can HMI terminals.
Example: audible alarm enabled when a machine cycle has been automatically paused and is now about to resume.
Example: a machine's RED general fault indicator has turned permanently ON. The machine's HMI is then referenced for the specific alarm.
Regards,
George