PCB Piezotronics 441A101, Installation And Operating Manual

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443B101/443B102 2
Manual 19854 Rev. D
ECN 50523
Before Operating
Electrostatic Discharge
High voltage electrostatic discharge
(ESD) can damage electrical devices.
To avoid triboelectric transfer:
1. Connect cables only with the AC power off.
2.
Temporarily “short” the end of the cable before
attaching it to any signal input or output.
Additionally, internal adjustments should be done
ONLY in an ESD-safe work area. Even ESD-protected
electronics can be vulnerable to extremely high volt-
age.
Equipment Ratings
This equipment operates at 104

F (40

C), in an
environment having 93% relative humidity. Its
frequency range is 50/60 Hz. Operation of this unit
is limited to environments having an altitude of less
than 2 000 meters. The pollution degree for
operation of the Model 440 is two (2), meaning that
normally, only non-conductive pollution occurs.
The overvoltage category is II, indicating the
transient voltage levels that may be tolerated by the
equipment.
For complete specifications, refer to the enclosed
specification sheet.
Grounding
Indiscriminate grounding of instruments can
introduce ground loop interference. To prevent this,
it is necessary to ensure that the signal ground lines
of the 443B and any other instruments with which it
is used are grounded at one point only in the meas-
urement system.
Connect the signal ground lines of all the instru-
ments together. This is done through the shields of
the input and the output cables used to interconnect
the instruments.
If an instrument with a mains socket chassis terminal
is used in the measurement system, check that a)
only one of the instruments has its signal ground
connected via the chassis to mains ground, and b)
the housing of the transducer is isolated from
grounded measurement sources.
If the measurement set-up is mounted in a metal
instrumentation rack, ensure that only one of the
instruments has its signal ground connected to the
chassis (and chassis connected to mains ground if
the unit has a mains socket chassis terminal).
Equipment Overview
The Model 443B Dual-Mode Amplifier is a
comprehensively
equipped charge and ICP
®
preamplifier intended for use with piezoelectric
pressure, force and vibration sensors. This amplifier
is particularly useful for field and laboratory
measurement
of acceleration, velocity, and
displacement vibration.
Designed to fit into the PCB Modular Signal
Conditioning System, the Model 443B may be used
as a single-channel stand-alone system or as part of
a four-channel package housed in a single cabinet. It
may be controlled remotely via an RS-232 interface
when used with a 441 Series chassis with computer
control.
ICP
®
accelerometers with TEDS electronics can be
auto-normalized using the Auto TEDS feature. Full
TEDS data may be read from the TEDS menu, or
through the RS-232 port. Additionally, sensor
sensitivity can be digitally selected, and the amplifier
can store up to five setups for easy recall.
The unit has unified output ratings, built-in
integrators for velocity and displacement, switchable
low and high pass filters, and a built-in reference
signal. The output is routed to portable Sony DAT
Recorders, scopes, and frequency analyzers. In addi-
tion, the Model 443B102 offers medium and long
time constant settings.
See Figure 3 in Appendix B for Block Diagram.
Components and Features
Input
The input signal is fed to the amplifier via the input
connector on the front panel. When sensors with