Raven Envizio Pro, Installation & Operation Manual

Page: 194 / 232

Appendix A
184 Envizio Pro and Envizio Pro II Installation and Operation Manual
Verification of Spreader Constant
To verify and refine the spreader constant, perform the following procedure:
1.
Weigh loaded truck and record the initial weight.
2.
Enter the product density in lbs/cu. ft. [grams/liter] under the Density button in the Calibration Settings
screen.
3.
Set the total volume to zero for the product node being tested.
4.
With the product node in the Manual mode, unload a portion of the load by toggling the boom switch on.
5.
Determine the actual weight unloaded by re-weighing the truck.
6.
Compare this weight to the total volume displayed on the field computer display. Perform the following
calculation to refine the spreader constant, if desired:
Where OSC = the Old Spreader Constant, TV = the Total Volume and AW = the Actual Weight unloaded
and CSC = the Corrected Spreader Constant.
For Example:
Using an Old Spreader Constant = 228 [797], Total Volume = 2000 lbs [4400 kg] and an Actual Weight
Unloaded = 1950 lbs [4290 kg]:
English:
The new Spreader Constant is 234.
Metric:
Repeat this procedure until the weight of the metered materials equals the total volume value.
Product Density
The density of the current product being applied must be entered in lbs/cu. ft. [grams/liter] when controlling a
granular application.
Note:
To increase the system accuracy when applying at low rates, use the decimal shift feature as
explained in the Decimal Shift section on page 110.
Rate Cal
The target application rate must be entered in lbs/acre [kg/ha] as the rate cal value. Consult the equipment
manual to ensure that the selected gate opening is capable of applying at this application rate.
Note:
The spreader constant must be recalculated anytime the gate opening is changed.
OSC TV
×
AW
-------------------------
CSC =
228 2000
×
1950
---------------------------
234 =
797 4400
×
4290
---------------------------
817 =