Charge Mode Accelerometers; Low Impedance Voltage Mode (Livm) Accelerometers; Velocimeter; Magnetic Pickup - Honeywell VXP System Maintenance Manual

System Operations

3.1.8.1 Charge Mode Accelerometers

Charge Mode accelerometers produce an electrical charge which is proportional to acceleration,
and which must ultimately be converted to voltage. The VXP AU has six built-in charge
converters to interface with this type of accelerometer. These sensors have a two pin circular
connector on them.
3.1.8.2

Low Impedance Voltage Mode (LIVM) Accelerometers

LIVM accelerometers have a built-in amplifier and provide a voltage output directly, but require a
constant current bias source. The VXP AU has 26 interfaces designed for LIVM type
accelerometers. These sensors have either a two pin or a three pin circular connector on them.

3.1.9 Velocimeter

Velocimeters are essentially accelerometers with a built-in amplifier and integrator circuit. In this
way, an output voltage is produced which is proportional to velocity in inches per second (ips).
Velocimeters require both positive and negative supply voltages, and employ a four pin circular
connector. The VXP AU has 16 interfaces designed for velocimeters.

3.1.10 Magnetic Pickup

The Model 3030 Magnetic Pickup is used to generate a rotor azimuth pulse. It has two pins and a
threaded circular shell containing a coil encased in epoxy. It attaches directly to the Acquisition
Unit.

3.1.11 Cables

All of the cables necessary to operate the VXP system are included in the kit. Each separate cable
attaches to a specific component and the Acquisition Unit. The Strobex cable is permanently
attached to the Strobex, and also connects directly to the Acquisition Unit.
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