RE-A 91610/12.2015,
Bosch Rexroth Corp.
Axial piston variable motor | A6VM series 71
HA – Automatic high-pressure related control
21
HA.R1, HA.R2 electric override, electric travel direction
valve
With the HA.R1 or HA.R2 control, the beginning of control
can be overridden by an electric signal to switching sole-
noid b. When the override solenoid is energized, the vari-
able motor swivels to maximum swivel angle, without inter-
mediate position.
The travel direction valve ensures that the preselected
pressure side of the hydraulic motor (A or B) is always
connected to the HA control, and thus determines the
swivel angle, even if the high-pressure side changes
(e. g. -travel drive during a downhill operation). This
thereby prevents undesired jerky deceleration and/or brak-
ing characteristics.
The travel direction valve (see page 24) is either pressure
spring or switched by energizing switching solenoid a,
depending on the direction of rotation (travel direction).
Electric override
Technical data, solenoid b with DIA45 R1
R2
Voltage
12 V (±20 %) 24 V (±20 %)
No override
de-energized de-energized
Position
V
g max
energized
energized
Nominal resistance (at 68 °F (20 °C))
4.8 Ω
19.2 Ω
Nominal power
30 W
30 W
Minimum required active current
1.5 A
0.75 A
Duty cycle
100 %
100 %
Type of protection: see connector version on page 62
Travel direction valve, electric
Technical data, solenoid a with DIA37 R1
R2
Voltage
12 V (±20 %) 24 V (±20 %)
Direction
of rotation
Operating
pressure in
ccw
B
energized
energized
cw
A
de-energized de-energized
Nominal resistance (at 68 °F (20 °C))
5.5 Ω
21.7 Ω
Nominal power
26.2 W
26.5 W
Minimum required active current
1.32 A
0.67 A
Duty cycle
100 %
100 %
Type of protection: see connector version on page 62
▼ Circuit diagram HA1R1, HA1R2
a
b
B
A
M
1
T
2
T
1
V
g min
V
g max
U
G
▼ Circuit diagram HA2R1, HA2R2
M
1
T
2
T
1
G
B
A
V
g min
V
g max
U
a
b
