Instructions for Micro-Trak
Seed Rate Control Systems
Used with Raven
440/450
Controllers
The value for Driven or Drive Sprocket refers to the number of
teeth on the sprocket.
To calculate Ratio for a single stage chain drive, use the
following equation:
(Driven Sprocket ÷ Drive Sprocket)
EXAMPLE: 32 ÷ 16 = 2.000
This means the Drive Sprocket will need to make 2 complete
revolutions in order for the Driven Sprocket to make 1
revolution.
To calculate Ratio for a two stage chain drive, use the following
equation:
(First Stage Driven Sprocket ÷ First Stage Drive Sprocket) x
(Second Stage Driven Sprocket ÷ Second Stage Drive Sprocket)
EXAMPLE: (32÷ 16) x (28 ÷ 16) = 3.500
In the above example, the First Stage Drive Sprocket will need
to make 3.5 complete revolutions in order for the Second Stage
Driven Sprocket to make 1 revolution.
To calculate Ratio for a three stage chain drive; use the
following equation:
(First Stage Driven Sprocket ÷ First Stage Drive Sprocket) x
(Second Stage Driven Sprocket ÷ Second Stage Drive Sprocket) x
(Third Stage Driven Sprocket ÷ Third Stage Drive Sprocket)
EXAMPLE: (32 ÷ 16) x (28 ÷ 16) x (24 ÷ 18) = 4.666
In the above example, the First Stage Drive Sprocket will need
to make 4.666 complete revolutions in order for the Third Stage
Driven Sprocket to make 1 revolution.
Calculating your Flow Cal for a Planter Drive
1. Rows equals the number of rows the drive is running.
ROWS = ______
2. How many seeds are dispensed per revolution of your Seed
Meter Disc?
SMD = ______
3. What is the Ratio of hydraulic motor revolutions to seed
meter revolutions?
RATIO = ______ to 1
4. How many teeth are there on your Motor Sensor Sprocket?
MSS = _____
1000 Seeds ÷
ROWS
= Seeds per Row
Seeds per Row ÷
SMD
= Seed Meter Revolutions
Seed Meter Revolutions x
RATIO
= Motor Revolution
Motor Revolution x
MSS
= Pulses per 1000 Seeds (Flow Cal)
EXAMPLE:
ROWS
= 12
SMD
= 30
RATIO
= 4.0
MSS
= 16
1000 Seeds ÷ 12 =
83.333
83.333 ÷ 30 =
2.777
2.777 x Ratio =
11.111
11.111 x 16 =
177.8
177.8 = Flow Cal or Pulses per 1000 Seeds.
FIRST STAGE DRIVEN
THIRD STAGE DRIVEN
THIRD STAGE DRIVE
SECOND STAGE DRIVEN
SECOND STAGE DRIVE
FIRST STAGE DRIVE
P/N 50289 Rev A • © 2009 • Page 10
