Change The Precharge Pressure - MTS Systems Landmark 370 Series Product Information

Item Description
11 Nitrogen Bottle
12 Nitrogen Bottle Pressure Gage
13 Regulator Output Pressure Gage
14 Regulator Shut-Off Valve
15 Regulator Output Pressure Valve
16 Nitrogen Supply Hose
17 Input Check Valve
18 Bleed Valve
19 Extension Hose
20 Gage Protector (factory set to limit pressure to the gage to approximately 1.4 MPa
(200 psi)
21 High Pressure Gage—0–21 MPa (0–3000 psi)
22 Low Pressure Gage—0–2.1 MPa (0–300 psi)
23 Chuck Valve
2. With an open-end wrench, turn the locknut counterclockwise on the accumulator valve
assembly to open the valve. Read the pressure on either the high or low accumulator charging
kit pressure gage.
A. If the pressure reading is other than the required pressure level recorded on the
accumulator, continue with the next subsection, "Change the Precharge Pressure".
B. If the pressure level corresponds to the level recorded on the accumulator label, turn
the locknut clockwise to close the valve and continue this procedure.
3. Open the bleed valve on the accumulator charging kit and remove the chuck valve from the
accumulator. Replace the valve stem cap and protective cover on the accumulator.

Change the Precharge Pressure

Often the precharge of an accumulator mounted on a hydraulic supply line is increased to enhance
system performance and reduce the transient HPS flow demands. Accumulators may be precharged
to 10 MPa (1500 psi) or more, although amounts above 14 MPa (2200 psi) will have less and less
performance effect in most situations. Be sure that you read the following warning before you charge
your accumulator.
MTS Landmark™ Tabletop Load Units - Product Information
Maintenance
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