Continental Hydraulics Installation Manual
Page 20 of 27
CEM-SA-B
CHI 1020687 01/2016
MIN:A / MIN:B (Dead band compensation)
MAX:A / MAX:B (Output scaling)
TRIGGER (Response threshold for the MIN parameter activation)
Command
Parameters
Unit
Group
MIN:i
x
MAX:i
x
TRIGGER x
i= A|B
x= 0… 6000
x= 3000… 10000
x= 0… 4000
-
0.01 %
0.01 %
0.01 %
STD
The output signal to the valve is adjusted by means of these commands. A kinked volume flow
characteristic is used instead of the typical overlap step for the position controls. The advantage
is better and more stable positioning behavior. At the same time, kinked volume flow
characteristics can also be adjusted with this compensation
8
.
If there should also be adjustment options for deadband compensation on the valve or valve
amplifier, it must be ensured that the adjustment is performed either at the power amplifier or in
the module.
If the MIN value is set too high, this has an effect on the minimum speed, which can then no
longer be adjusted. In extreme cases this leads to oscillation around the controlled position.
MAX:A
MIN:A
MIN:B
MAX:B
Input
O
u
tp
u
t
non lineare Flow
compensation
Standard deadband
compensation
TRIGGER
8
Various manufacturers have valves with a defined nonlinear curve: e.g. a kink at 40 or 60 %
(corresponding to 10 % input signal) of the nominal volume flow. In this case the TRIGGER value should be
set to 1000 and the MIN value to 4000 (6000).
If zero lapped or slightly underlapped valves are used, the volume flow gain in the zero range (within the
underlap) is twice as high as in the normal working range. This can lead to vibrations and jittery behavior. To
compensate this, the TRIGGER value should be set to approximately 200 and the MIN value to 100. The
gain in the zero point is thus halved and an overall higher gain can often be set.
