MTS Series 505G2 SilentFlo Hydraulic Power Unit Model 505G2-30 - Manual (Page 37)

Precharging the Surge Suppressor Accumulator
Model 505G2.20 - 505G2.30 SilentFlo™ HPU Installation 37
Precharging with a gas other than dry nitrogen will cause the existing
nitrogen within the surge suppressor to be mixed with the new gas.
Mixing gases can produce unpredictable results.
Use only dry nitrogen gas to precharge the surge suppressors.
3. Connect the nitrogen supply hose from the supply bottle pressure regulator
output to the input check valve on the charging kit.
4. Open the nitrogen bottle valve. Check the nitrogen bottle pressure gage on
the regulator. (The bottle must contain sufficient pressure to provide an
adequate gas volume.)
5. Monitor the regulator output pressure gage and adjust the regulator output
pressure valve to the required level.
Opening the regulator shut-off valve too far can cause a rapid flow rate and
an extreme pressure differential.
A rapid flow rate with a high pressure differential across the input check
valve can damage the check valve seal(s).
Do not allow rapid flow rates. Open the regulator shut-off valve only far enough to
permit a gradual transfer of gas.
6. Slowly open the regulator shut-off valve until gas is heard escaping from the
accumulator charging kit bleed valve. Allow gas to slowly escape for
approximately ten seconds, and then close the bleed valve. Immediately
close the regulator shut-off valve before the pressure reading on either the
high or low charging kit pressure gage exceeds the pressure level of the
accumulator.
7. Open the locknut. Slowly open the regulator shut-off valve until the pressure
indicator on either the high or low charging kit pressure gage begins to rise.
When the pressure is at the required pressure level, close the regulator shut-
off valve.
8. Close the locknut.
9. Open the bleed valve on the charging kit and remove the chuck valve from
the accumulator.
Install the valve stem cap and protective cover. Close the valve on the nitrogen
bottle.
WARNING
CAUTION