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MODEL V550 VME
8-CHANNEL LVDT SCANNER
V550 LVDT scanner features
  • Conditions eight LVDT-type position transducers.

  • Self-scanning with onboard microprocessor.

  • Presents scaled, normalized position data to the VME bus.

  • 16-bit resolution with programmable noise filtering.
The model V550 is a 6U, one-slot VME module which will acquire position data from up to eight LVDT (linear variable differential transformer) position sensors. The LVDT sensors are excited by an ultrastable synthesized sinewave generator, and conditioned by a precision 16-bit A/D converter followed by digital signal processing. The resident microprocessor supervises scanning and signal conditioning, and places updated position data in VME-accessible dual-ported data registers for instant access from the VME bus.
The V550 provides 16-bit resolution, allowing sub-micron measurement with commercially available LVDTs. Users may select a range of DSP filtering factors to trade off position noise against acquisition rate.

The V550 provides unprecedented signal acquisition accuracy. Total RMS error (including absolute error, noise, and all drifts) is typically under 1.5 LSBs, equivalent to less than 25 PPM of full-scale span.

Model V550 VME 8-Channel LVDT Scanner Specifications
CONFORMANCE ANSI/IEEE 1014-1987 VMEbus specification. VXIC specification, Rev1.4.
DEVICE TYPE  Register based slave: A16:D16:D08(EO).
PACKAGING  Single-width, 6U VME or B-size VXI module.
POWER REQUIRED  +12 : 500mA; +5 : 3A; -12 : 500 mA
LVDT DRIVE
Standard 3 Vrms, 2.4 KHz; other levels and frequencies available. Drive is differential to minimize capacitive error effects. Wiring shorts on any channel will not damage the module or disturb measurements of other channels.
RESOLUTION
16 bits
ACCURACY Better than +- 50 PPM
STABILITY
Temperature influence < 1 PPM per degree C; Long-term drift< 4 PPM per year.
SCAN TIME Time to scan all eight channels varies from 84 ms to 1.8 s depending on user-selected filtering factors.
DATA FORMAT  Signed two's complement 16-bit data.
CONNECTORS  Two front-panel mounted female DB-25s, five leads per LVDT.
Highland Technology V550 VME 8-Channel LVDT Scanner Data Sheet