High Pressure Switch
: This is a dry contact that signals the system to shut down if
the pump discharge or membrane pressure exceeds the desired value. This
is a normally open contact. When an open circuit condition exists between
the two terminals, the system will operate. If contact is made between the
two terminals, the system will shut down. An LED will indicate when the
system is in a state of high pressure shut down. The alarm reset button must
be pressed to resume operation after a shutdown due to high pressure.
Tank Level
: The controller has two inputs that accept the dry contacts for the high
level and low tank level switches. If the controller is in the “Tank Feed” mode
(see the “Settings menu” section of this manual for further discussion), these
switches read the water level in the RO product storage tank and turn the
pump
ON
or
OFF
depending on the level. Each switch should be installed in
the tank so that the contacts close when the water level falls below that
particular switch. When the tank is full, the RO pump is turned off and the
“Tank Full” LED is on continuously. As the tank is drawn down, the LED
blinks. The LED turns off when the RO pump restarts to fill the tank (2 level
switch operation).
The AL250-V2 may be configured to use only one tank level (high tank level)
switch. Again the system must be operated in the “Tank Feed” mode (see
the “Settings menu” section of this manual for further discussion). When this
configuration is being used; the “Tank Full” LED will indicate when the
system is in a state of high tank level (level switch open). The system starts
and stops based only upon high tank level and the “High Tank Startup Delay”
setpoint. When the level drops (the switch closes), the system will re-start
after the “High Tank Startup Delay” (see “Settings Menu” section of this
manual for further discussion). The “Tank Full” LED will blink while the “High
Tank Startup Delay” timer is timing.
Pretreatment Interlock
: This is a dry contact that signals the system to shut
down when a pretreatment device is not functioning or regenerating.
This could be used on a water softener, multimedia filter, chemical feed
pump, pressure differential switch on prefilters, etc. This contact is
normally closed. When a circuit is complete between the two terminals
the system will operate. If contact is broken the system will shut down.
An LED will indicate when the system is shut down due to pretreatment
interlock. The system will restart itself when the contact is closed.
Chemical Pump Failure:
This is a dry contact that signals the failure of the
chemical injection system. This input differs from the “Pretreatment
Interlock” in that it does not allow the system to restart. This contact is
normally open. When an open circuit condition exists between the two
terminals, the system will operate. If contact is made between the two
terminals, the system will shut down. An LED will indicate when the
system is shut down due to chemical pump failure.
All input connections on the AL250-V2 provide a supply voltage and are designed for
dry contacts.
Do not apply voltage to the inputs as permanent damage may
result.
Mode
The AL250-V2 is designed to operate in one of three modes. The mode of operation
is selected from the Settings menu.
The
stand-by mode
is intended to place the system in a temporary non-
operational mode. When the system is placed in this mode, it will
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