OPERATION
INTRODUCTION
The Chemigem is designed for use with all types of pools and to measure and automatically
adjust the Chlorine and pH levels in the pool water.
Once levels are finally set or adjusted, the unit should be left alone.
The unit has been factory-set to achieve 650 millivolts Chlorine (ORP) and 7.7pH .
It has been found that if ORP is maintained at 650 millivolts, the kill time of E-coli type
bacteria is about one second.
If the ORP is lowered to 550 millivolts, the same organisms could take up to 2 hours to be
eliminated.
If the unit is used with these factory-set points as the selected levels, it should obtain
approximately 2-4 ppm Chlorine and 7.7 pH, providing the stabilizer level is at 50 ppm. If the
stabiliser level is 30 ppm or less, the Chlorine will be around 1 ppm.
READING THE DISPLAY PANEL
E
N
I
R
O
L
H
C
0
5
6
T
E
S
0
0
6
(ORP)
H
p
7
.
7
T
E
S
2
.
7
What do the Chlorine and pH Numbers Represent?
The Chlorine (ORP) number is the activity of the chlorine (see explanation of ORP (Below)
and measures in millivolts.
The pH number is the measure of acid / alkalinity and is displayed in units of the pH scale.
What is ORP?
The Chemigem is designed to measure and automatically adjust Chlorine (ORP) and pH
levels in the pool water. (Refer above). As an explanation of what ORP is, the following is
provided:
For over 20 years operators in many parts of the world have used Oxidation-Reduction-
Potential (ORP or REDOX) values as a measure of Chlorine activity in water. ORP is a
measure of the oxidising properties of the Chlorine in the water and is easily monitored by the
Chemigem multi-electrode (probe).
When the multi-electrode (probe) is placed into water containing Chlorine it behaves like an
electric cell and creates a small but measurable electric voltage. This voltage is proportional to
the activity of Chlorine in the water.
It has been found that if ORP is maintained at 650 millivolts, the kill time of E-coli type
bacteria is about one second. If the ORP is lowered to 550 millivolts, the same organisms
could take up to 2 hours to be eliminated.
The test kit will measure Chlorine as parts per million (ppm) but the activity level of the
Chlorine (and therefore the kill-time) depends upon the other materials dissolved in the pool
water.
For an ORP controller to work properly the pH, Total Dissolved Solids (TDS), stabiliser (iso
cyanuric acid) and calcium hardness must be maintained within the recommended levels.
RAINBOW
POOL
PRODUCTS
PTY
LTD