Product information 21/64
RE 50129-B/02.19, Accumulator shut-off block type ABZSS, 0532VAW,
Bosch Rexroth AG
5 Product information
More detailed information on operating conditions, connection dimensions and
performance limits of the respective accumulator shut-off block can be found in
data sheets 50128 and 50131, see chapter 1.2 "Required and amending
documentation".
5.1 Performance description
An accumulator shut-off blocks is a control block for overpressure protection
of hydraulic accumulators. On exceeding the maximum operating pressure, the
integrated pressure relief valve is opened and the overpressure is relieved. The
pressure relief valve must not be used for any control tasks. It is only to be applied
as overpressure valve.
5.2 Product description
The accumulator shut-off block serves for the protection, isolation and relief of
hydraulic accumulators. It is classified based on its use according to the directive
2014/68/EU article 4, section 3.
The connection between the accumulator shut-off block and the hydraulic
accumulator is realized by means of an accumulator adapter.
An optional additional electrically operated 2/2 directional seat valve can take over
the following functions:
• “Emergency stop” function (valve normally open, variant ABZSS...E):
Enables automatic unloading of the hydraulic accumulator in case of shutdown or
power failure.
• Pressure holding function (valve normally closed, variant ABZSS...C):
Enables automatic pressure maintenance in case of shutdown.
The selected functionality must be considered when it comes to the design of the
safety concept of the machine.
The hydraulic accumulator is protected from inadmissible overpressure by means of
the pressure relief valve.
Sufficient difference between the pressure set at the pressure relief valve and the
operating pressure must be ensured. Response of the pressure relief valve should be
prevented, if possible.
The pressure relief valve must not be used for any control tasks.
Accumulator adapter
2/2 directional seat valve
(optional)
Pressure relief valve
