MTS Series 505 SilentFlo Hydraulic Power Unit Model 505-180 - Manual (Page 59)

Precharging the Optional Surge Suppressor
Model 505.60 - 505.180 SilentFlo™ HPU Installation 59
A. Enable the first pump.
B. Press the Run/Low Pressure button. The enabled pump will sequence
on and start running in low pressure.
C. Press the High Pressure button. The enabled pump will sequence to
high pressure.
D. Check for unusual noises or leaks. If a problem is found, press the Stop
button. You must correct the problem before you continue.
E. Verify that the Hyd Fluid Pressure display indicates high pressure
[typically 21 MPa (3000 psi)].
F. If necessary, refer to the appropriate procedure, and adjust the
hydraulic pressure for the enabled pump.
G. Press the High Pressure button to return to the low pressure mode.
H. Enable the next pump and disable the pump you just checked.
I. Repeat Step 8C through 8H for each remaining pump.
J. Enable one pump only and select low pressure.
K. Run the pump in low pressure for about three hours to filter the new
hydraulic fluid.
9. After filtering is complete, press the Stop button.
Precharging the Optional Surge Suppressor Accumulator
The surge suppressor, if provided, smooths out the ripple caused by the pulsing
action of the pump as it pressurizes the hydraulic fluid. The surge suppressor is a
cylinder that has an outer sleeve that is pressurized with nitrogen. The gas
pressurized sleeve dampens the pressure pulses.
The surge suppressor is mounted to the output of the hydraulic pump inside the
reservoir.
It is normal for a small amount of surge suppressor precharge loss to occur during
operation. Because of this gradual reduction in precharge pressure, the pressure
should be checked and recharged (if necessary) at regular intervals.
Determining a
pressure check
interval
The precharge pressure checking intervals of your surge suppressor depends on
how your system is used. Vigorous use causes more rapid pressure loss and thus
requires checking and recharging more often.
Initially, check the surge suppressor precharge pressure every month or 160
operating hours. If the precharge pressure changes more than 1.4 MPa (200 psi)
during this time period, recharge the surge suppressor and check the pressure
twice as often in the future. If the precharge pressure changes less than 1.4 MPa
(200 psi), check the pressure half as often.