MTS Series 111 Accumulator - Manual (Page 31)

displacement, and duration. Start with one month intervals until you determine that another interval is
more appropriate.
• Maintain a log book on the condition of the precharge at each check. Use this data to determine if the time
between checks should be increased or decreased and if maintenance is required.
• Because the precharge pressure level varies with a temperature change, the level should always be
checked at the same temperature. If it is not, use one of the following formulas to determine if the precharge
level is acceptable.
Degrees Celsius
Description Item
Current pressure 1
Original pressure 2
273 + (current temperature) 3
273 + (original temperature) 4
Degrees Fahrenheit
Description Item
Current pressure 1
Original pressure 2
460 + (current temperature) 3
460 + (original temperature) 4
• If a pressure line accumulator has a pressure level change of ±1.4 MPa (200 psi) between checks, the
accumulator requires maintenance or the time interval between checks needs to be shortened.
• If a return line accumulator has a change of ±50% of the original pressure level between checks, the
accumulator requires maintenance or the time interval between checks needs to be shortened.
• If the precharge pressure level increases at each check interval, this indicates that fluid is collecting on
the gas side (a small amount of fluid leakage is normal). When the precharge pressure level cannot be
Series 111 Accumulator Product Information 31
6.0 Maintenance