Model V420

8-channel VME isolated resistance simulator

Overview

Features:
  • 8 channels of fully isolated 2/4 wire precision resistance/RTD simulation
  • True 4-wire resistance measurements on all channels
  • Suitable for simulating resistors, platinum/copper RTDs, thermistors, strain gauges, load cells
  • Resistance programmable from 5 Ω to over 1 MΩ in five ranges
  • RTD mode programmable for 100 Ω, 500 Ω and 1 kΩ platinum RTDs or 10 Ω copper RTDs
  • Directly accepts temperatures in Celsius
  • Fast, monotonic, glitch-free resistance changes allow for realistic RTD simulation with no dips or spikes
  • Channels may be used in series or parallel for additional voltage and current capability
  • Simple register based VME interface with no handshaking required
  • Users may directly program resistances or RTD simulation (copper or platinum) temperatures
  • Any channel is switchable to front-panel calibration check connector for in-system test without disconnecting field wiring
  • Optional built-in self test (BIST)
  • Clearly labeled dipswitches set VME address; no jumpers, headers, or trimpots
Description:

The V420 is an 8-channel, isolated, programmable resistance simulator. It uses entirely solid-state simulation to eliminate transient errors associated with relay switching, and provide for monotonic resistance changes. Channels are individually programmable in four resistance ranges, from 5 ohms to 65.5K. Channels can operate from microvolts up to 35V / 50mA. Overload protection and channel error detection are included.

Any channel may be rerouted, under software control, to the front-panel calibration-check connector, allowing the board to be tested for calibration by a precision DVM without disturbing the connections to the equipment under test. The BIST option adds an onboard precision ohmmeter, allowing loopback checking and full automatic self-test. Optional external termination and bridge-completion boards are available.