Instruction Manual 2009
Rev 3
DFS2 Doppler Flow Switch
3
Adjustments
Range Selection : (refer JP1)
Range 1 (0 – 2 m/s) :- Jumper in position “1”
Range 2 (0 – 6 m/s) :- Jumper in position “2”
Setting Low Flow Trip Point :
Move slide switch “S1” to “Lo” position. Adjust the low trip potentiometer until the
bar graph displays the required alarm setting as a percentage of the flow range
selected.
Example : Range 1 (0 – 2 m/s)
Bar graph display – 50%
Trip point setting – 1,0 m/s
Setting High Flow Trip Point
Move slide switch “S1” to “Hi” position and adjust high trip potentiometer to display
the required alarm setting.
NB
Return slide switch to centre position for normal operation.
Delay-Off Timer T1 :
Under normal operating conditions the flow may fluctuate beyond the high or low trip
settings momentarily. The adjustable 0 – 60 sec. timer is adjusted with
potentiometer “T1”. Turn clockwise to increase the delay before the relay operates.
Delay-On Timer T2 :
If the flow switch is used for pump control it is necessary to over-ride the trip settings
during start-up, until the flow is established.
The adjustable 0 – 60 sec. timer is adjusted with potentiometer “T2”. Turn clockwise
to increase the delay before the relay operates.
