PC104-73LD1
FOUR LVDT
"PROGRAMMABLE"
TRACKING CONVERTERS
WITH WRAP-AROUNDSELF TEST. +5 VDC ONLY
FEATURES:
鈥?Only +5 VDC.
鈥?16 bit Resolution
鈥?Accuracy 0.025% FS
鈥?Continuous background bit testing with Reference and Signal loss detection
鈥?360 Hz to 10 Khz
鈥?Transformer isolated
鈥?Programmable reference and signal voltages
鈥?Accurate Digital Velocity outputs
鈥?Latch feature
鈥?Synthetic reference compensates for
鹵60擄
phase shift
鈥?No adjustments or trimming required
鈥?8 bit or 16 bit data bus versions
DESCRIPTION:
This PC104 compliant stackthrough module offers four (4) separate transformer isolated
鈥淧ROGRAMMABLE鈥?LVDT/RVDT-to-Digital tracking converters
with extensive diagnostics, digital
velocity, and (A+B) outputs.
Instead of buying cards that are set for specific inputs, the uniqueness of this
design makes it possible to order our generic card that is Autoranging between 2.0 and 28 volts for 4-wire LVTD
input. For 2-wire inputs, the card can be programmed and reprogrammed in the field for any excitation and signal
voltage between 2.0 and 28 volts. This card uses a derived reference ratiometric design approach that is insensitive
to magnitude, temperature, frequency and phase shift effects. The conversion technique assures that the output
will change only when the LVDT position changes and will ignore excitation voltage variations. The 鈥淟atch鈥?feature
permits the user to read all channels at the same time. Reading will unlatch that channel. The converters utilize a
Type II servo loop processing technique that enables tracking, at full accuracy, up to the specified rate.
Intermediate transparent latches, on all data and velocity outputs, guarantee that current valid data is always
available for any channel without effecting the tracking performance of the converters. The optional on鈭抌oard
excitation supply can be factory set for a particular voltage and frequency, or can be supplied as field
programmable. To simplify logistics, Part number, S/N, Date code, & Rev. are stored in permanent memory
locations.
Major diagnostic are incorporated
that offer substantial improvements to system reliability because user is
immediately alerted to channel malfunctions. Self-Test (POST) diagnostic can immediately initiate (D3) test.
See
Programming Instructions for further details.
Three different tests (one on-line and two off-line) can be
selected:
The (D2) test
initiates automatic background bit testing. Each channel is checked over the Signal range to a
measuring accuracy 0.1% FS, and each Signal and Excitation is monitored. Results are available in registers The
testing is totally transparent to the user, requires no external programming, has no effect on the standard
operation of this card and can be enabled or disabled via the bus.
The (D3) or POST test,
if enabled, starts an initiated bit test that disconnects all channels from the outside world
and connects them across an internal stimulus that generates and measures multiple voltages to a test accuracy
of 0.1%FS. Results can be read from Status registers. External excitation is not required. The testing is totally
transparent to the user, requires no external programming, and can be enabled or disabled via the bus. Power-On
(POST) test can be enabled or disabled via the bus.
The (D0) test
is used to check the card and the interface. All channels are disconnected from the outside world
allowing user to write any number of input voltages to the card and then read the data from the interface. External
excitation is not required.
Apex Signal, A Division of NAI, Inc.
Bohemia, NY 11716 USA
www.naii.com
Code: 0VGU1
Model PC104-73LD1 Specifications
PC104-73LD1 Rev E
SHEET 1 OF 4
1
2
3
4
