Flow switch IFM SI6700

1 Flow sensor IFM SI6700

The flow sensors indicate the flow with 10 leds. At a configurable switch point, an digital output will be set.

File:Display 1.pngFile:IFM SI6700 Display 2.png

1. Display after correct adjustment at full flow.
2. Display shows only half flow: digital output is not set.
3. Flow to high (last LED flashing)

2 Adjustment

Green LEDs 0…9 are indicating the flow speed (0,05…1,0 m/s, factory setting).
Orange/red LED is indicating the switch point.
output closed, i.e. flow is higher than switch point => LED is orange
output open, i.e. flow is lower than switch point => LED is red

Check if all strainers/filters in the circuit are clean, Pump is running in right direction and circuit is OK!
High flow adjustment
1. Let the normal flow circulate in the installation.
2. Press the pushbutton File:IFM SI6700 rightArrow.png and keep it pressed.
-> LED 9 lights, after approx. 5 s it flashes
3. Release the pushbutton

Low flow adjustment
1. Let the minimum flow circulate in the installation or ensure flow standstill
2. Press the pushbutton File:IFM SI6700 leftArrow.png and keep it pressed
-> LED 0 lights, after approx. 5 s it flashes.
3. Release the pushbutton. The unit adopts the new value and passes into the operating mode.

Adjusting switch point
1. Briefly press the push button File:IFM SI6700 leftArrow.png or File:IFM SI6700 rightArrow.png => the switch point flashes
2. Press the button File:IFM SI6700 leftArrow.png or File:IFM SI6700 rightArrow.png to change the switch point
3. Set the switch point to LED 7

3 Rough calculation:

Works only if sensor is still on factory settings (==1m/s).

compare the actual flow with the nominal flow of the system (see name plate of pump or piping scheme)

actual flow can be estimated according to the pipe diameter:

flow [m³/h] = 3/10000 * (no. of LED + 0,5) * inner pipe diameter² [mm]

example: nominal pipe diameter: DN 80 => inner pipe diameter approx. 84 mm

LEDs 0 to 8 are green

=> flow = 3/10000 * (8 + 0,5) * 84 * 84 = 17,99 m³/h