2
2.2 Calibration of Switch
Vibrating fork switch with Integral Controller is provided with DIP switch. It functions are explained as
below
DIP Switch Details:
SW1 - S/L : NA - should be OFF
SW2 - FSS : Fail Safe
SW3 – OND : On time delay settings
SW4 - OFD/CAL: Off delay settings and calibration.
VFSL Two part system is provided with push switch for fail safe high and low selection and not
required to be calibrated
Normally all the switches are calibrated at factory and need not required to be calibrated. However if required
follow the procedure below.
For liquid application, before calibration make sure that instrument is in OFF condition. Dip the fork blades in
liquid up to approximately 30 percent of blades only. Switch on 4
th
DIP switch. Then power on instrument, red
led start blink for five times. While calibration fork blades should be dip 30 percent. Don’t move while
calibration, it should be fix. After 5 blinks of led, make 4
th
switch in OFF condition.
Now calibration is complete and check the functioning of instrument.
2.3 Delay Setting
2.3.1 ON Delay
Make on 3
rd
dip switch, then red led start blink. Count blink for no. of seconds we need to set the delay.
If no. of counts finish then make OFF the 3
rd
dip switch. This set for on delay of 3 sec.
After that check the operation. If we set 3 seconds delay then when medium touch the calibration point level
then after 3 seconds, relay will change its contacts.
2.3.2 OFF Delay
Make on 4
th
dip switch, then red led start blink. Count blink for no. of seconds we need to set the delay.
If no. of counts finish then make OFF the 4
th d
dip switch. This set off delay.
After that check the operation. If we set 3 seconds delay then when medium away from the calibration point
level then after 3 seconds, relay will change its contacts.
2.3.3 Fail Safe Selection
When 2
nd
switch is in off condition it is fail safe low mode and when it is on, then it is in fail safe high mode.
