9
Automatic Control
CONTROL BOX - CONFIGURATION
Valve Selection (15)
The Valve Drive Selector Dip Switch (15) is used to select the type of valve to be driven when
used with the
M
CB2 Control Box. Following are the types of valves supported:
PT
- Proportional Time
On/off (bang-bang) valve drive
PV
- Proportional Voltage
Danfoss valve drive
PC
- Proportional Current
Various dither frequencies (Hz) and
dither amplitudes (% of maximum correction)
Additional information on the types of supported valves are in Appendix B.
Reference Appendix J for a list of common valve models and their Control Box settings.
NOTE:
The
M
CB
1
Control Box supports PT valves only. Switch settings are not functional.
M
CB
2
Settings are as follows:
If the control box power was on during valve selection, cycle the box power before proceeding.
Proportional Current Valves: Dither is a signal which is constantly sent to the valve that causes
the spool to vibrate and stay lubricated. This reduces hysteresis and stiction.
Choose a setting closest to the manufacturers recommendations.
If cylinder lines or cylinder are vibrating from dither, select a higher frequency and/or
lower the % amplitude.
If the valve is sticking or sluggish, select a lower dither frequency and/or a higher
% amplitude.
PT
PV
PC
100 Hz, 10%
PC
50 Hz, 10%
PC
200 Hz, 10%
PC
400 Hz, 10%
PC
50 Hz, 20%
PC
100 Hz, 20%
PC
200 Hz, 20%
PC
400 Hz, 20%
Switch Bats
in ON position
