Pump displacement vs. control current
100%
100%
Displac
emen
t
0
Signal Current (mA(DC
Avg
))
Max Current
H1 FDC control
N
a
b
a = Forward Threshold
b = Reverse Threshold
N = Neutral Override Current
P301 443
∆
p = 0 bar
∆
p = 0 bar
∆
p = 300 bar
Reverse
Forward
Control Response
H1 controls are available with optional control passage orifices to assist in matching the rate of
swashplate response to the application requirements (e.g. in the event of electrical failure). The time
required for the pump output flow to change from zero to full flow (acceleration) or full flow to zero
(deceleration) is a net function of spool porting, orifices, and charge pressure. A swashplate response
table is available for each frame indicating available swashplate response times. Testing should be
conducted to verify the proper orifice selection for the desired response.
H1 pumps are limited in mechanical orificing combinations. Mechanical servo orifices are to be used only
for fail-safe return to neutral in the event of an electrical failure.
Typical response times at the following conditions:
∆p
250 bar [3626 psi]
Viscosity and temperature
30 mm²/s [141 SUS] and 50 °C [122 °F]
Charge pressure
20 bar [290 psi]
Speed
1800 min
-1
(rpm)
Response time, FDC 045/053
Stroking direction
0.8 mm [0.03 in] Orifice
Full flow to neutral
1.9 s
Full forward flow to full reverse flow
2.8 s
Technical Information
H1 Axial Piston Single Pumps, Size 045/053
Control Options
32 |
©
Danfoss | May 2017
11063344 | BC00000059en-US1001
