Blocks

The IBEX concept of a block is similar to SECI, in that it is a relevant piece of information chosen by the scientist that will be displayed on the instrument dashboard and, if required, can be logged into the datafile.

In IBEX, a block is, to all intents and purposes, an alias to a process variable. For example, the block Chop1Freq on LARMOR is defined to be the process variable IN:LARMOR:CS:SB:Chop1Freq. It is much simpler to refer to a block than to refer to a process variable. Utilities like genie_python know about blocks, and you can use commands such as cset to access Chop1Freq. However, you can access blocks using the name IN:LARMOR:CS:SB:Chop1Freq with any standard EPICS tool.

Process variables are defined in more detail on the Process Variables page.

Alarms

An IBEX block may be in alarm as well as having a value. Alarms signify potential problems with the data

Disconnected

A disconnected status implies that the user interface cannot access the variable which has been requested.

Examples:

• The relevant IOC is not running - for example, the relevant ioc is not listed in the current configuration
• The IOC is running on another computer, and there is no network availability

These alarms appear with either a purple border or a solid purple background in the user interface.

Invalid alarm

An invalid alarm signifies that there was a problem acquiring this piece of data. Data marked with an invalid alarm should generally not be trusted.

Examples:

• The hardware has become unplugged or switched off
• The hardware replied in an unexpected way
• A setpoint has not been set (it will remain in an undefined state until set)

These alarms appear with a purple border in the user interface.

Major alarm

A major alarm signifies that there is a serious problem with the data being reported by a device. Data marked with an major alarm may require attention from an equipment expert.

Examples:

• A fault status is being reported by the hardware
• A chopper is not in the correct operation mode

Note: it is possible to set your own limits on a value going into major alarm - please ask the IBEX team if you would like help setting this up

These alarms appear with a red border in the user interface.

Minor alarm

A minor alarm signifies a warning with the data being reported by a device. Data marked with a minor alarm should be checked, but if you are confident that the data is correct and within the expected ranges, can be ignored.

Examples:

• Motor parked on a limit switch
• Helium level in a cryostat falling low

Note: it is possible to set your own limits on a value going into minor alarm - please ask the IBEX team if you would like help setting this up

These alarms appear with an orange border in the user interface.