MTS Series 298 Hydraulic Service Manifold - Manual (Page 16)

Series 298 Hydraulic Service Manifold 16
Component Identification
Introduction
Component Descriptions
COMPONENT DESCRIPTION
Servovalve A Series 252 Servovalves can be mounted on the actuator manifold. A second
servovalve of the same rating can be added to increase the maximum hydraulic
flow.
Shutoff valve An optional shutoff valve allows the use of a second servovalve of a different
rating. The shutoff valve lets you select which servovalve to use on the actuator
manifold.
Servovalve mounting
cover plate The plate covers the second servovalve mounting when only one servovalve is
used. The plate is removed when a second servovalve is installed.
Return accumulator An accumulator can be installed on the hydraulic return line. The accumulator
reduces hydraulic pressure fluctuations.
Proportional valve
(298.12 only) The proportional valve (also called an electrical pressure reducing valve)
controls the hydraulic pressure to the servovalve without affecting the rest of the
hydraulic system. It allows the hydraulic pressure to be ramped from off to low
and from low to high pressure. The ramp rates are also applied when turning the
hydraulics off except when an interlock occurs and the pressure is stepped to
zero.
The ramp rates are set by the system controller. The system controller can also
set the level of low pressure.
On/off valve (298.11 only) The on/off valve on the Model 298.11 Actuator Manifold allows hydraulic
pressure to be applied to or removed from the servovalve without affecting the
rest of the system. The valve is controlled by the system controller.
Hydraulic input/return
ports The input and return ports are the connections to the hydraulic lines controlled
by the hydraulic power unit.
Differential pressure
switch (included with the
inlet filter) The differential pressure switch is mounted across the inlet filter. It provides an
indication of a dirty filter condition. One type of switch is a pop-up visual
indicator; another type provides an electrical indication of a dirty filter condition
(this requires appropriate cabling to the system controller).
Pressure accumulator An accumulator can be installed on the hydraulic high pressure line. The
accumulator smooths the hydraulic power unit output and provides additional
hydraulic fluid for high instantaneous flow demands.
Inlet filter (optional) A 3-micron or 10-micron (absolute) inlet filter prevents passage of dirt particles
into the servovalve(s).
Hydraulic Ports Hydraulic ports for lifts, locks, and grips support load units with hydraulically
controlled crosshead lifts and locks. Hydraulic grips also use these ports. The
high pressure port is not affected by the high and low pressure control of the
actuator manifold. A hydraulic return port completes the optional hydraulic
circuit.