Great Plains EHPR Valve Calibration - Manual

Great Plains Mfg., Inc.
Calibration Procedure 1
©Copyright 2008 Printed 12/10/2008 401-565M
EHPR Valve Calibration
3PYP Planter Reverse Steering
Used with:
• 3PYP s/n A1025+
• Field-upgraded lower 3PYP s/n
General Information
These instructions explain how to calibrate the Electro-
Hydraulic Proportional Reducing (EHPR) valve which
controls reverse steering on new, upgraded or repaired
3PYP planters.
Background: EHPR valves control the direction of rotation
and rate of movement of the caster wheels. The valves
require an Imin (input minimum) value to be stored into
the ECU (electronic control unit) during the first setup of
the steering system. The Imin value determines the mini-
mum threshold of movement of the caster wheels left and
right. The Imin values need to be calibrated properly for
the system to respond correctly with the tractor wheel
rotation. Failure to calibrate or calibrating incorrectly may
make the system have unintended movements or have a
sluggish response to the tractor wheel movement.
The calibration of the Imin value needs to be done only
once for each EHPR valve. New planters are shipped
from the factory with EHPR valves calibrated. Field-
installed steering systems are not factory calibrated.
EHPR calibration is required upon any of these events:
• Steering system installation
• EHPR valve cartridge (not coil) replacement
• ECU replacement
• ECU firmware upgrade
Tools Required
• 833-510C HHCT (Hand-Held Calibration Tool)
• 401-312M 3PYP Planter Operator Manual
• 401-312Q 3PYP Planter Pre-Delivery Manual
• The tractor to be used with the planter, having:
300-608 steering console installed, and;
tractor steering sensor installed
Notations and Conventions
“Left” and “Right” are facing in the
direction of machine travel. An orienta-
tion rose in the line art illustrations
shows the directions of Up, Back, Left,
Down, Front, and Right.
Kit Description
401-615A HAND HELD CALIBRATION TOOL KIT
When you see this symbol, the subsequent instructions
and warnings are serious - follow without exception.
Your life and the lives of others depend on it!
!
Figure 1
833-510C HHCT
29197
U
D
F
B
L
R
Figure 2
Right / Left
25050
R
L