15
Instruction Manual
SECTION 3 - OPERATION
3.3.3 Calibration in External Mode
1. Since pump output is governed by an
external device such as Flow meter-Pulser,
LIQUITRON™ Controller, or 4-20 mA DC signal
from an instrument with an LMI
®
Analog-to-
Digital Converter,
only the output per stroke
may be calibrated
.
2. With pump primed and discharge tubing
connected to the injection point as it would be
in normal service, place Foot Valve Assembly
in a graduated container with a volume of
1000 ml or more.
3. Switch pump to
Internal
mode with Speed
Adjustment Knob set at 100% until air is
exhausted from suction line and pump head.
4. Switch pump
OFF
and refill graduated container
level to a starting point.
5. Switch pump
ON
and
count the number of
strokes
for exactly one minute, then switch
pump
OFF
.
6. Note volume pumped during the calibration
period of one minute. Divide into this the number
of strokes to determine the volume of solution
pumped per stroke.
Example:
720 ml in 240 strokes = 3.0 ml per stroke.
Multiply this by your expected stroke rate per
minute, per hour or per day and compare with
desired output requirements.
7. Turn Stroke Adjustment Knob to your best
estimate of required correction and repeat
calibration procedure.
Note:
It may be helpful to decrease the speed of the
pump in order to count the number of strokes.
For accuracy count at least 120 strokes.
3.4 METHODS OF EXTERNALLY
TRIGGERING OR PACING A7
AND A8 PUMPS
Switches or transistors must be capable of
switching 24V DC at 15 milliamperes. Minimum
time in low impedance state (
ON
) is 25 milliseconds.
Minimum time in high impedance state
(OFF)
is
50 milliseconds.
NOTE:
Pins 1 (Brown wire) and 2 (White wire) must be
connected / shorted together in order for the
pump to be ‘
ON
’ in external mode.
4. Opto
Isolator
2. NPN Transistor
Base goes high
to trigger pump
White
3. PNP Transistor
Base goes low
to trigger pump
1. Switch Closure
Switch closing
triggers pump
PIN
3
2
3
2
3
2
3
2
Blue
− W
hite
+ Blue
− W
hite
+ Blue
− W
hite
+ Blue
Figure 15. Triggering Through External
Control Connector
