The Model 5M78 is a single-channel conditioner of phase-sensitive carrier-amplifier
design. Intended for applications involving transformer-coupling to the transducer
bridge (as with rotary-transformer torque sensors), this conditioner can also be used in
conventional installations when high sensitivity is required or where the electrical
environment is especially noisy. Responding only to the modulated carrier frequency,
the 5M78 rejects extraneous voltages that can cause errors in DC systems,
particularly when there is a need to “blow up” a portion of the transducer range.
User-adjustable phase and symmetry controls are provided.
calibration resistor is 59 kilohms, 1% which is located internally to the 5M78 case.
1
G
ENERAL
D
ESCRIPTION AND
S
PECIFICATIONS
Model 5M78 AC Strain Gage Module
Access switch settings via the front
panel of the 5M78 by gently pulling the
clear plastic cover (from the bottom
side) so the cover rotates open from
DIN AC Strain Gage Conditioner
M
ODEL
5M78
AC Strain Gage
C
ONDITIONER
Module
5M78
1.A.1.5M78
G
ENERAL
D
ESCRIPTION AND
S
PECIFICATIONS
5M78.1
or without power to the unit. Once
completed, return the cover to the
View of Side Label of the Model 5M78 AC Strain Gage Module
the top. Use a small tool or finger to
place the switches to the left or right
position as you face the front of the
module. This process can be done with
original position.
AC Strain Gage Phase Operation
Due to the AC modulated aspects of the
5M78 AC Voltage excitation circuit, the 5M78
contains a "PHASE" adjustment which
aligns the transducer's return output signal
to the conditioner's demodulator. When
the demodulator is aligned properly through
calibration, maximum amplitude and
accuracy are achieved.
The Model 5M78's is calibrated by means of a “two-point (dead-weight)” or
shunt-calibration technique, which are outlined in section three. The supplied shunt
92342.00
