The Xpac is available with a substantial list of optional equipment. Most items can be retrofitted in the field. Refer to the appropriate Technical Memo for additional details.

Position Transmitter (PM12)
The position transmitter provides a loop-powered, two-wire 4-20 mA signal proportional to actuator position. The transmitter's output is optically isolated from the electronics. Both an active and passive transmitter are available. A passive position transmitter is similar to other two-wire transmitters in that an external DC power source is required. An active two-wire transmitter with its own 24 VDC power supply is available.

Manual Override (PM15)
A declutchable handwheel connects to the outboard end of the motor shaft. Since the handwheel utilizes the same hydraulic circuit as the motor, the required torque is low. On actuators with high thrust or torque or long strokes, a 5/16 inch hex drill drive may be substituted for the handwheel or a 5:1 geared hand crank on a separate power module is available.

Limit Switches (PM13)
Limit switches are either yoke-mounted or PCP-mounted. Yoke-mounted switches are activated by the actuator shaft and function independently. The PCP-mounted switches are activated electrically and include an alarm relay.

Alarm Indicator (PM14)
The PCP is able to perform various diagnostic functions. If the actuator cannot follow the control signal, the alarm relay will change state to provide remote indication. The alarm relay is included on the position transmitter and PCP-mounted limit switches.

Surge Control (PM20)
By utilizing a spring, solenoid and solid state relay, the Xpac can provide high-speed motion in one direction. The position can be to any intermediate point or strictly to the end (trip).

Pulse Operating System (PM16)
In place of or in conjunction with the normal analog control signal, pulse or contact signals can provide control input to the actuator. Three- or four-wire, AC or DC signals in the range of 24 to 120 volts can be used.

Auxiliary Controls - External (PM17)
To limit access to the control enclosure, a window (to view the position display) and external push buttons can be provided. The push buttons will only allow manual override of actuator position.

Auxiliary Controls - Remote (PM17)
Manual operation of the actuator from a remote location is available with the remote control option. Three contact inputs are required: auto/remote (two position), open (momentary contact), and close (momentary contact). Power for the switches is supplied by the control enclosure. Manual stations are available from REXA.

Spring Failure (PM4)
While still maintaining the control capability available in the standard fail-in-place version, the spring failure provides a high degree of safety. The spring is continuously engaged and is compressed or expanded during operation. A bypass valve which connects both sides of the hydraulic cylinder is kept closed by a normally open (NO) solenoid.

Accumulator Failure (PM21)
Use of an accumulator eliminates the need to "oversize" the actuator as with a spring-fail unit. The accumulator puts no load on the power module during normal operation, so actuator size is reduced. REXA's unique accumulator technology uses the power module to recharge the accumulator, thus eliminating the need for a separate recharge pump and associated plumbing. This feature allows all components of the accumulator system to be located on the actuator.

Stem Boot
Linear actuators installed at locations containing airborne particles may be subject to accelerated seal wear. The normal motion of the stem can transport contaminants through the seals, causing damage. A stem boot over the shaft offers protection from the environment. Standard on linear actuators with thrusts greater than 10,000 lb or strokes longer than 6 inches.

Split Clamps
On linear actuators mounted at unusual angles or with reduced accessibility, a split clamp connection between the actuator and driven device is available. The difficulties of stem rotation, shaft insertion and jam nuts are eliminated. Standard on linear actuators with thrusts greater than 10,000 lbs. or strokes longer than 6 inches.