Priva Compass Installation Manual page 97

EC Interface VP8658
1. Set the unit to maintenance mode:
• Go to Water Room > Water system > Settings > Stop water system for maintenance and select
IMMEDIATE.
• NutriFit and NutriFlex: close the valve between the unit and the main irrigation line. With
large system pumps, the pressure in a closed main irrigation line can rise considerably. If
this is the case, it is advisable to slightly open the discharge valve on the side of the unit and
discharge the water to the mixing tank using a hose.
• Switch the system pump on manually.
• NutriJet: open the rinse valve at the end of the main irrigation line.
• NutriJet Bypass: switch the external pump on manually.
2. Go to manual override > dosing channels and change the setting to override.
3. At override position you can set the percentages with which you wish to open the dosing channels.
For a usable calibration the EC value must be within the unit's normal control range, for
instance around 2 mS.
4. Collect some water with fertiliser and measure its EC value using a reference EC meter.
5. Calculate the desired output signal (in mV) of the EC Interface VP8658: desired output signal=EC
value x 500.
6. Connect a digital multimeter to test point TP0 (Gnd) and TP5 (signal EC sensor 1) on EC Interface
VP86583.
7. Adjust the potentiometer R13 until the multimeter shows the desired output signal (calculated
in step 5).
8. Connect a digital multimeter to test point TP0 (Gnd) and TP7 (signal EC sensor 2) on EC Interface
VP86583.
9. Adjust the potentiometer R33 until the multimeter shows the desired output signal (calculated
in step 5).
10. Go to manual override > dosing channels and change the setting to automatic.
11. Set the unit back to operating mode:
• Go to Water Room > Water system > Settings > Stop water system for maintenance and select
NO STOP.
• NutriFit and NutriFlex: open the valve between the unit and the main irrigation line. If the
discharge valve on the side of the unit has been used, close this valve.
• Set the pump switch of the system pump to automatic.
• NutriJet: close the rinse valve at the end of the main irrigation line.
• NutriJet Bypass: switch the external pump to automatic.
Installing Priva Compass - 00.014
EC-DSS interface
95