Section 2 – Installation
10
2.6
External Control Settings
The
easy
FLOW-VS
has the ability to be controlled by an external device. For example, it can be
connected to a
mini
CHEM
pH controller to control the pH of an industrial process. Using the
correct cable connections and jumper settings, the
easy
FLOW-VS
can be set up to be externally
controlled in the any of the following ways…
1. Simple On and Off switching, operating at the speed setting of Dose Rate control.
2. Variable speed operation, proportional to a 4-20 mA input, where 4mA is stopped and 20mA is
full speed.
3. Variable speed operation, proportional to a 0 – 1V DC input, where 0V is stopped and 1V is
full speed.
4. Either of the variable speed external control settings above can be set up with a manual
override to switch the unit off.
Refer to the following diagram when setting up the External Control connections…
Notes
To access the circuit board’s settings, remove
the four screws at the corners of the front panel
and remove the lid. Please use caution, to avoid
damaging any connecting cables.
In the table below, “Switch” under H4 refers to
an external switch to turn the
easy
FLOW-VS
on
and off. This can be in the form of standard
on/off switch or the relay contacts of a process
control unit.
“Link” under H4 refers to linking the two
terminals with a piece of wire.
When removing jumpers, we recommend that
you fit it to one of the pins. This way, it will not
be lost if the jumper is to be replaced at a later
time.
“n/c” means “No Connection” at that terminal.
External Control Mode
H1
H4
J1
J2
J5
J7
J6
Simple On / Off Switching at Dose
rate setting
n/c
Switch
Off
Off
Off
On
On
4-20mA Variable Speed
4-20 mA
Link
On
On
On
On
Off
4-20mA Variable Speed with Manual
OFF override
4-20 mA
Switch
On
On
On
On
Off
0-1 V DC Variable Speed
0-1 V
Link
Off
Off
On
On
Off
0-1 V DC Variable Speed with Manual
OFF override
0-1 V
Switch
Off
Off
On
On
Off
No external control (factory default
settings)
n/c
Link
Off
Off
Off
Off
On
