M
CB
3
Installation Manual
Page 49
APPENDIX C
Hydraulic Valve Guide
PC - Proportional Current Valve:
PC valves are proportional spool valves.
The maximum current supplied to the valve solenoid is equal to machine voltage divided by
coil resistance.
Pulse Width Modulation (PWM) is used to create the < 100% proportional current signal.
The PC signal energizes 1 coil at a time which slides the valve's spool back and forth
changing the valve's orifice size which changes the oil flow rate.
If the valve's maximum current rating is less than the maximum supplied current, (machine
voltage / coil resistance), use the Max % On setting in the Valve Setup Menu § 5.5 to lower
the maximum supplied current to within the valve's maximum rated current. Reference
Appendix A for PC Valve Identification and Setting Recommendations.
Application Note: PC Valves are typically fast, but not always accurate.
Direct operated solenoid PC Valves are limited in flow rates to about 8 GPM (30 l/m) due to
the force capability of 12V solenoids.
Lower
Correction
Raise
Correction
On Grade
Deadband
0%
50%
100%
Valve Min.
Correction
Valve Speed = 1%
Valve Speed = 50%
Valve Speed= 100%
PC Valve Signal
(% of Maximum Current)
Valve Speed= 100%
Valve Speed = 50%
Valve Speed = 1%
