Danfoss H1 Series Technical Information page 75

Technical Information
H1 Bent Axis Variable Displacement Motors, Size 060/080/110/160/210/250
Controls – nomenclature, description
© Danfoss | December 2016
Control start setting range (pressure above case pressure)
p (possible settings per MMC.- adjustable)
start
P
max allowable
Control ramp
From 100% to 20% displacement
From 100% to 0% displacement
Formulas to calculate start and end input command
Control type Input command (bar)
Start input command
DH
End input command
Where:
V
Maximum, theoretic possible motor displacement per revision (cm
gmax
V Minimum displacement setting of desired unit (cm
gx
V
Maximum displacement setting of desired unit (cm
gy
x Minimum displacement (%)
y
Maximum displacement (%)
Pressure Compensator OverRide (PCOR) with Brake Pressure Defeat (BPD) configuration
A brake pressure defeat (BPD) shuttle valve ahead of the pressure compensator prevents operation in the
deceleration direction (when motor is running in pump mode). This is designed to prevent rapid or
uncontrolled deceleration while the vehicle/machine is slowing down.
Pressure compensator override with brake pressure defeat is mainly used in systems with pumps having
electric or hydraulic proportional controls or automotive controls.
The brake pressure defeat must be controlled by a 2-line external signal based on direction of motor
rotation, see the following table:
Pressure Compensator OverRide (PCOR) operation
Motor rotation High pressure port
CW A
CW A
CCW B
CCW B
1)
Differential control pressure between ports XA and XB: p
W
Warning
Zero degree capability results in a high risk of overspeed and drops in efficiency if the motor operates
between 0–20% displacement.
2 to 30 bar [29 to 435 psi]
Control start setting + 50 bar [725 psi]
14 bar [203 psi]
17.5 bar [254 psi]
% displacement All sizes (bar)
from 100% p ± 0.5
start
from y% max. (1 - V /V
gy gmax
at 0% p + 17.5 ± 2.5
start
at x% min. (1 - V /V
gx gmax
3
/rev)
3
/rev)
Control pressure on port
XA
XB
XA
XB
= 2.5 bar [36 psi] and p
min
11037153 | BC00000043en-US1103 | 75
) x 17.5 + p ± 0.5
start
) x 17.5 + p ± 2.5
start
3
/rev)
1)
PCOR function
no
yes
yes
no
= 50 bar [725 psi]
max