IPS Controllers M920 Owner's Manual page 15

M920 & M920W pH/Dual ORP Controller Owner's Manual
c. Run the sensor cable into the controller through the strain relief
marked "temp" and connect to the terminal block on the front
circuit board marked "Temp".
5. Electrical Connections (Should be completed by a licensed
electrician)
a. Verify that the M920 controller power is OFF.
b. Connect the pH feeder connection to the appropriate peristaltic
pump or other device.
c. Connect the ORP feeder connection to the appropriate
peristaltic pump or other device. Note: There is another
connection port for ORP2.
d. Method 1 (recommended): Connect the AC power cord to the
load-side of the circulation pump circuit. This will only provide
power to the M920 when the circulation pump is running.
e. Method 2: Connect the AC power cord to a GFCI power source,
or separately purchased IPS Controllers PressureSwitch (part #
PS100).
f. Connect the pH sensor connector to the corresponding lower
port (labeled pH) at the right edge of the controller.
g. Connect the ORP sensor connector to the corresponding upper
port (labeled ORP) at the right edge of the controller.
6. Chemical injection must be inserted in the return line, after
(downstream) any equipment.
7. Optional connection to a Salt Chlorine Generator (SCG)
The M920 controller is capable of controlling (turning on/off) a SCG
depending on the current ORP reading. This action can be accomplished
using a 120V or 240V relay, or by connecting the SCG to the "normally
open" dry contact relay (ORP1) included with the M920 controller. When
using the ORP1 Dry Contact Relay, the black plastic jumper identified as
HD2 needs to be repositioned from the lower position (see Figure 4) to
the open pegs at the top.
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