User Guide

3332
turn the Flow Rate Control to 7 (9/12). Run
the test again to verify the results.
Overheating Prevention System (for
BL7913 and BL7914 only)
The pump automatically shuts down if it
heats up to the point where irreparable dam-
age could occur.
Once the unit detects an excessive tem-
perature, it will alert the operator with a red
LED.
BL
7914
Black
Stone
IP 54
WITH
TRANSPARENT
COVER
INSTALLED
OVERHEATING
50
60
40
30
70
20
80
90
10
0 100
FLOW
%
105
215
LITRES/HOUR
0110
115
220
240
Actual Flow Rate
The actual flow rate depends upon the oper-
ating pressure which includes resistance at
the injection fittings, hose and piping, the
chemical viscosity and suction lift. The Flow
Rate Control adjusts the flow up to 100% of
the rated output. Less back pressure will
increase the output, more will decrease it.
To determine the correct setting for your
application, use the following procedure.
1. Be sure that the pump is primed and that
the output connections are completed at
the injection point.
2. Place the foot valve as-
sembly (HI 721005) in a
graduated container with
500 mL of the solution to
be dosed.
3. Switch the pump from
OFF to the 100% setting
and run until the system
has been fully reprimed.
Switch OFF and refill the
container to the 500 mL
level.
4. Switch the pump ON to
the estimated setting and
run for a specific amount
of time (e.g.1 minute).
Count the number of
strokes, length of time,
and volume pumped.
Note: It is suggested that you run the test
for as long as possible to maximize
the accuracy.
For example, if at the maximum setting of
100% you find you pumped 200 mL in one
minute, your hourly output would be 12 li-
ters/hour (200 mL x 60 min. = 12000 mL/hr).
If your application called for 9 liters/hour,
50
60
40
30
70
20
80
90
10
0
100
FLOW RATE %
50
60
40
30
70
20
80
90
10
0
100
FLOW RATE %