MDC Torque
Description
Value
Torque required to move handle to maximum displacement
1.4 N•m [12.39 lbf•in ]
Torque required to hold handle at given displacement
0.6 N•m [5.31 lbf•in]
Maximum allowable input torque
20 N•m [177 lbf•in]
C
Caution
Volumetric efficiencies of the system will have impacts on the start and end input commands.
MDC General Information
In difference to other controls the MDC provides a mechanical deadband. This is required to overcome
the tolerances in the mechanical actuation.
The MDC contains an internal end stop to prevent over travel. The restoring moment is appropriate for
turning the MDC input shaft back to neutral only. Any linkages or cables may prevent the MDC from
returning to neutral.
The MDC is designed for a maximum case pressure of 5 bar and a rated case pressure of 3 bar. If the case
pressure exceeds 5 bar there is a risk of an insufficient restoring moment. In addition a high case pressure
can cause the NSS to indicate that the control is not in neutral. High case pressure may cause excessive
wear.
Customers can apply their own handle design but they must care about a robust clamping connection
between their handle and the control shaft and avoid overload of the shaft.
Customers can connect two MDC’s on a tandem unit in such a way that the actuation force will be
transferred from the pilot control to the second control but the kinematic of the linkages must ensure
that either control shaft is protected from torque overload. To avoid an overload of the MDC, customers
must install any support to limit the setting range of the Bowden cable.
C
Caution
Using the internal spring force on the input shaft is not an appropriate way to return the customer
connection linkage to neutral.
General information - CCO
For the MDC with CCO option the brake port (X7) provides charge pressure when the coil is energized to
activate static function such as a brake release. The X7 port must not be used for any continuous oil
consumption.
Neutral Start Switch (NSS)
The Neutral Start Switch (NSS) contains an electrical switch that provides a signal of whether the control
is in neutral. The signal in neutral is Normally Closed (NC).
Service Manual
H1 Pumps 069/078, 089/100, 115/130, 147/165, 210/250
Operation
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©
Danfoss | May 2018
520L0848 | AX00000087en-US0308
