PV850
World Precision Instruments
11
The
µPump
will inject on the high to low transition of the incoming TTL pulse.
No Injection
INJECTION
No Injection
Fig. 15—The injection happens on the high to low transition of the TTL pulse.
OPERATING INSTRUCTIONS
Changing the Injection Parameters
Pr ss an
r n t s tt n s ar a to a
ss t S tt n s
nu Pr ss Port Off to
turn on t r ssur ort (PO O )
Fig. 16—(Left) Touch the setting area in the bottom right corner to access the Settings menu.
Fig. 17—(Right) Touch the Port OFF button to enable the injection port.
2. On the Settings screen you may choose the Pump Mode as TIMED or MANUAL. In
the MANUAL mode, the valve stays open for as long as the Inject button or foot
s t s
r ss
n t
o
t ran s
•
MANUAL mode–The pressure valve opens and remains open as long as the
Inject button or foot switch is pressed or a 5 V TTL pulse is triggered by an
external pulse generator.
•
TIMED mode–An electronic timer controls the duration that the pressure valve
stays open, and the Inject button, foot switch or 5V TTL trigger serves only to
start the timer. Although the timer control allows you to set sub-millisecond
burst intervals, the true burst interval is limited by the mechanical response of
the valve, which is about 0-2 seconds, depending on the pressure.
out ut onn tor ro u s a o
out ut ( ) orr s on n to
the time interval during with the eject pressure valve is energized. At all other
t
s t on tor out ut s o ( )
3. To change the parameters, just touch the screen on the parameter you want to
change. A box appears around the parameter to highlight it. Adjust the parameter
by turning the knob. To change the dial adjustment speed, press the knob on the
front of the
PV850
. The snail mode allows movements in 0.01 increments to the
compensation pressure only, and only when it is below 3.0 PSI. Both conditions
must be met. The running man changes it in increments of 0.
NOTE
: When adjusting the COMPENSATION PRESSURE under 3.0 PSI, you may
set it in 0.01 PSI increments.
