SHEET 6 OF 20
the display permit the user to increment and decrement the value of each digit.
Note that the display automatically carries over to the next digit(s) when
incrementing past 9 and decrementing past 0.
6. RANGE – Four-position momentary switch/indicators determine the time
range (milliseconds, seconds, or minutes) or selects frequency mode for the
“OFF-TIME DURATION” switch.
OTHER CONTROLS, INDICATORS, AND CONNECTORS
7. ERROR – A red LED that lights when the operating parameters are set
outside allowable limits.
8. START -- This momentary contact push button switch starts action in the
INTERNAL mode by triggering a single pulse (ONE SHOT) or starting a series
of pulses (CYCLE).
9. STOP - This momentary contact push button switch stops any timing that
may be active and restores the valve to the OFF condition. If the instrument is
operating in a mode that is independent of timing (EXTERNAL CYCLE MODE),
this control will have no effect.
10. INTERNAL/EXTERNAL – These four momentary switch/indicators select
the operating mode and signal sources for the system.
11. INPUT (TTL) – This BNC jack allows the unit to be triggered from an
external source. The input signal should be low (0 volts) for off and high (+5
volts) for on.
12. SIGNAL – This green push button/LED serves two functions. As an
indicator, it illuminates to show a logic high on the external signal source. As a
control, it serves as an input that is active as a signal source. It is active when
depressed.
13. OUTPUT (TTL) – A logic high (TTL) output is provided at this BNC jack
whenever the valve driving circuit is active in any operating mode.
14. POWER – A retained action switch to control the AC power to the unit. The
face of this switch will illuminate when depressed if proper AC voltage is present
and the fuses are functional.
15. VALVE – This jack is the connection to the valve through the supplied valve
cable.
16. RS-232 – This jack is the RS-232 connection for remote monitoring and
control.
