Inputs/Outputs with the X-1B Interlock

The relay contacts that the X-1A interlock will receive from the X-1B interlock are:

BENNO	EXPERIMENT B MASK ENABLE (normally open)
BENC	EXPERIMENT B MASK ENABLE (common)
	A set of relay contacts that will form a closed circuit only when the X-1B branch line is in a configuration where it is safe to have beam present (i.e. no equipment can be damaged by beam power).

BACNO	EXPERIMENT B ACTIVE (normally open)
BACC	EXPERIMENT B ACTIVE (common)
	A set of relay contacts that will form a closed circuit when the X-1B branch line is in a configuration for taking beam (i.e., the X-1B mirrors are not fully retracted. For Operations Coordinator information.

It is expected that the X-1B beamline interlock will automatically close valves (and open contacts BENNO/BENC if necessary) to isolate the X-1B beamline vacuum system from the X-1B mirror chamber in case of poor vacuum in the X-1B beamline.

In addition, the X-1A interlock system is connected to the pressure setpoint relay contacts on the G2 vacuum gauge controller. Since G2 is located on the X-1B mirror chamber, X-1B supplies this gauge and controller. The status of the G2 pressure setpoint relay will be provided to X-1B as the contacts:

G2NO	G2 normally open
G2C	G2 common
	A set of relay contacts that are only closed when the G2 pressure is below the setpoint.