REV E, ECN 12876, 08/18/16 2
OPERATING GUIDE
MODEL 3196C HIGH TEMPERATURE CHARGE MODE ACCELEROMETER
INTRODUCTION
Model 3196C is a charge mode accelerometer
designed to measure vibration of surfaces at
temperatures up to +500 degrees F. This accel-
erometer uses an ultra stable piezoceramic crystal
material in its self-generating seismic element. This
material exhibits less than +9% increase in sensitivity
from room temperature to +500 degrees F.
Model 3196C may be used with various
charge amplifiers of the vibration type. (As opposed to
the DC coupled electrostatic types.)
We especially recommend the Dytran in-line
charge amplifier Model Series 4705A, for use with the
3196C. This inexpensive miniature charge amplifier
adapts the 3196C for use with any LIVM (constant
current type) power unit. Model 4705A features BNC
input and output connectors and mounts in-line
between the 3196C and the power unit.
DESCRIPTION
Refer to Outline/Installation drawing 127-3196C.
Model 3196C is packaged in a hermetically
sealed 300 series stainless steel housing and features
a transverse mounted ceramic-to-metal sealed TNC
connector. The unit is installed by use of 3 8-32 x 1/2
inch long socket head cap screws, (supplied). The
mounting screws thread into 3 matching threaded
holes which must be provided in the mounting surface.
Model 3196C also features a connector
housing design which will accept Dytran's "Immersion
Proof" cable/boot assembly to protect the cable
connection against moisture and other contaminants.
INSTALLATION
To mount Model 3196C, it is necessary to drill
and tap 3 equally spaced 8-32 mounting ports on a
1.188 dia. bolt circle. For best high frequency
response, the contact area of the accelerometer must
be selected or prepared to be flat to .001 TIR. The
holes must be drilled perpendicular to the mounting
surface to within 2 degrees of angular error.
After drilling and tapping, clean the area to
remove all traces of cutting oil and machining chips.
Spread a thin layer of silicone grease on the
three contact surfaces of the 3196C. Locate the accel.
over the tapped holes and engage the three mounting
screws through the holes in the flange and into the
tapped holes. Thread the mounting screws into the
tapped holes and torque to 15 pound inches.
Inspect the mating surfaces to ensure that the
accelerometer is snugged down tightly in intimate
contact with the test surface at all three contact points.
If the surfaces appear to be meeting squarely,
the accelerometer is ready for connection of the cable.
INTERCONNECTION
The recommended cable assy for the 3196C
is the Dytran Model 6425A03. This cable is a 3 feet
long low-noise coaxial with TNC connector on both
ends.
Connect the cable to the 3196C and connect
the other end of the cable to the charge amplifier.
Apply lock wire if applicable.
If you are using a fixed sensitivity charge
amplifier such as the Model 4705A, the system
sensitivity is the product of the charge sensitivity of the
accel. (in pC/G) and the sensitivity of the charge
amplifier (in mV/pC).
Example:
Accelerometer sensitivity: 8.0 pC/G.
Charge amplifier (Model 4705M2) sensitivity:
12.5 mV/pC.
System sensitivity is:
8.0 pC/G x 12.5 mV/pC = 100 mV/g
MAINTENANCE AND REPAIR
Should you experience a problem with your
system, contact the Dytran factory for technical
assistance in analyzing and trouble shooting the
problem. If the product must be returned for evaluation
and/or repair, you will be given an RMA (returned
materials authorization) number and instructions for
returning the instrument to the factory. Do not return
the instrument without first obtaining this authorization
to return.
