438D Vibration Switches (mm/sec)

An Economical Machine Monitor with Remote Sensor

More than a simple switch, but not an expensive monitor either, the 438D is a single-channel vibration monitor that can be located in a centralized location, remote from operating equipment. The 438D is on guard around the clock to provide cost-effective protection of motors, pumps, fans and a wide range of other rotating equipment. It provides continuous digital readout of the vibration level, and signals when a predetermined setpoint level is reached.


Measurement mode


Frequency range

Dependent on tranducer type and any special filtering (See “Transducer Types” below)

Analog output

4 – 20 mA DC, proportional to full scale range

Input power

110V or 220V AC, field selectable


2, adjustable from 0-100% of full scale


LEDs: yellow for “Alarm”, red for “Trip”, green to indicate range

438D operating temperature

-20 to +160F (-29 to +71C)


NEMA 4, with hinged cover Dimensions: 9.5″H x 7″W x 4″D (24.1 x 17.8 x 10.2cm)
Weight: 6.5 lbs (2.9kg)


Flat surface, 8-3/4″ x 4″ (22.2 x 10.2cm) bolt pattern

Cable entry

Transducer cable entry and cable grip provided; power and control cable entry by customer.

Field Adjustable Settings

Full scale range

0 – 25 or 0 – 75 mm/sec

Alarm & trip setpoints

0 to 100% of full scale range

Relay time delay

0 to 20 sec. per relay

Relay state

Normally de-energized (open below setpoint) or normally energized (closed below setpoint)

Relay configuration

Latching or non-latching

Relay inhibit

Inhibits relay operation during start-up or machine maintenance

Input power

110V or 220V AC

Transducer Types

4033-400 (Velocity)

Frequency range: 20 to 1,500 Hz
Operating temperature: -20 to +400F (-29 to +204C)

4033-500 (Velocity)

Frequency range: 20 to 1,500 Hz
Operating temperature: -20 to +500F (-29 to +260C)

4034 (Velocity)

Frequency range: 12 to 1,000 Hz
Operating temperature: -30 to +160F (-34 to +71C)

4071A (Acceleration)

Frequency range: 2.1 to 3,500 Hz
Operating temperature: -58 to +180F (-50 to +82C)

4073 (Acceleration)

Frequency range: 0.8 to 10,000 Hz
Operating temperature: -65 to +250F (-54 to +121C)