Showa 5683, Руководство по эксплуатации

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. MEASUREMENT
4.1 Cautions before Measuring (Refer to Table 4-1)
Before starting measurement, check the following points:
Items Cautions Reasons
The joints must be soldered, and the connectors must
be properly connected. Prevents poor connections, noise, and
instability in operation.
The insulation resistance of strain gauges must be equal
to or greater than 60 M
Ω
.
Prevents instability in operation as well as
noise from entering the equipment.
Installing the bridge box and strain gauges in the
presence of strong magnetic or electric fields must be
avoided.
Prevents noise from entering the equipment.
Install the bridge box and strain gauges in environments
where there is as little moisture as possible and the
ambient temperature is not high.
Prevents instability in operation.
The leads that connect strain gauges to the bridge box
should be as short as possible and should be shielded.
Prevents reduction in the gauge factor and
deterioration in output linearity.
Prevents noise from entering the equipment.
Installation
environment for strain
gauges and bridge
box
The interconnecting cable, which connects the bridge
box to the
amplifiers unit, should be as short as possible.
(The amplifiers automatically compensates for bridge
voltage drops with its cable length compensation.)
Prevents a bridge voltage drop, which may
result in an error between the signal and the
internal calibrator.
The amplifier system must be used in environments
where the ambient temperature ranges from -10 to
+50
°
C and the ambient humidity ranges from 20 to 85%
RH (with no condensation).
Prevents instability in operation.
Install the amplifier system in environments
where acceleration of mechanical vibrations is
less than 3 G (3000 rpm, 0.6 mm
P-P
)
Prevents damage and noise from entering the
equipment.
Installing the amplifier system in the presence of strong
magnetic or electric fields must be avoided.
Prevents noise from entering the equipment.
Installation
environment for
dynamic strain
amplifier system
The housing case must be properly grounded (when the
system operates on AC power).
Prevents noise from entering the equipment.
Select the bridge supply voltage in accordance with the
strain gauge to be used. Prevents measurement errors due to
generation of heat in strain gauges.
The connectors must be properly connected.
Prevents instability in operation and poor
connections.
Care must be taken not to smear the input connector
with oil, dirt, or anything else. Prevents instability in operation and poor
connections.
Verify that the power supply voltage is within the range
of specifications.
AC: 85 – 132 V, or 180 – 264 V
DC: 10 – 30 V
Check that the polarity of the battery is correct,
especially when 12 VDC is used.
If the supply voltage is less than the lower
limit, failures in operation may occur. If the
supply voltage is higher than the specified
upper limit, heat may be produced, which
may result in damaging electronic
components.
If the polarity of the battery is not correct, the
amplifier system will not operate. (However,
the system and the battery will not be
damaged though.)
Operation of dynamic
strain amplifier
system.
Do not apply pressure to strain gauges when units are in
the auto balancing mode.
Applying pressure to strain gauges in auto
balancing mode causes the bridge to be
unbalanced.
Table4-1 Precautions before Measuring (1)