2.1 Introduction
2.2 Front Panel Operation
2.2.1 Keypads
2.2.1.1 Status Keypad
The UGA can be in one of six modes (5 states, function): OFF,
READY, IDLE, INDIVIDUAL, BAKE, and LEAK TEST.
Each state can be reached from the other state with some restric-
tions. For example, BAKE state can be reached from READY, IDLE,
INDIVIDUAL, or OFF state. And LEAK TEST function can be
reached only from READY, not from any other states. But during
LEAK TEST function, the system can go to OFF. The UGA can be
stopped from any condition. The stop command is handled on an
emergency basis.
When the system is at vacuum sufficient to support RGA operation,
we refer to the state of the system as the “Ready” state. Careful
control of the UGA is required to get to the Ready state safely. This
is achieved with proper vacuum control. After the system is in the
Ready state, it can perform the function of analyzing gas; running
the RGA and collecting data. The UGA allows automatic control
and individual control. Automatic control means that the UGA
will perform the pre-designed sequences to reach the requested
state: Ready state by pushing “START/WAKE” button, Idle state
by pushing “SLEEP” button, Off state by pushing “STOP” button.
Individual control means that each component of the UGA can be
controlled individually by pushing a component button. These two
control modes are easily interchangeable. For the detailed opera-
tional schematics, refer to Appendix B, the state diagram.
The left-hand keypad on the front lower panel of the instrument
indicates the status of the instrument. It is a flow diagram showing
which components are active at any given time. We will refer to
this keypad as the “status keypad”.
Phone: (408)744-9040
www.thinkSRS.com
UGA Series Universal Gas Analyzers
Guide to Operation
2 –
