Agilent Technologies Eyesys Mini-B/A, Instruction Manual

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Eyesys Mini-B/A Gauge Controller
9
Setpoint 1 and Setpoint 2 Switches
Setpoints are easily selected by turning a digital rotary switch to one of sixteen settings.
Switch positions are labeled in groups of decades. For example, selecting 5 in the –4 group
selects 5x10
-4
for a setpoint.
Setpoint 1 covers from 5 Pa to 5E-5 Pa/50 to 5E-7 mbar/50 to 5E-7 Torr. The Setpoint 1 LED
illuminates and Relay 1 closes (pins 4 and 12 of J1) when pressure falls below Setpoint 1
level.
Setpoint 2 covers from 5E-2 to 5E-7 Pa/5E-4 to 5E-9 mbar/5E-4T to 5E-9T. The Setpoint 2
LED illuminates and Relay 2 closes (pins 5 and 15 of J1) when pressure falls below
Setpoint 2 level.
For positive relay operation, setpoints clear when pressure rises 20% above the setpoint
level, rather than immediately above. For example, the 5x10
-8
setpoint triggers when
pressure falls below 5x10
-8
, and clears when pressure rises above 6x10
-8
.
The Serial Communications Option is capable of setting setpoints to any level. Setpoint ON/
OFF status is also able to be polled by Serial Communication. See Appendix A “Serial
Communications Option” for details.