CR21

Micrologger®

Retired Product
(not available for purchase)

The CR21 featured an integrated design with built-in power supply, keyboard, and display. It looks very similar to, and is often confused with its replacement, the 21X Micrologger. The CR21 stored up to 608 data points in internal memory.

A typical field-based CR21 consisted of:
    CR21 or CR21L Micrologger with
    CR21 Instruction Set (PROMs)
    Alkaline or Rechargeable Power Supply (in base)
    Weatherproof Enclosure (new and old)


Features

  • Replaced by the 21X Micrologger® (now retired), CR23X Micrologger®
  • Manufactured from 1979-1985
  • Self-contained datalogger with built-in keyboard and power supply
  • Specialized sensors required; some no longer available
  • Stored 608 data points in internal memory (volatile)
  • ASCII data format
  • Some repairs no longer available

Specifications

  • Seven single-ended analog inputs (-0.2 to +2.5 Vdc or
    -2 mV to +25 mV, FSR)
  • Two pulse count channels (150 Hz (CH 8) and 50 Hz (CH 9), maximum input frequency)
  • One 4 Vac excitation channel
  • Three 2 Vdc sensor excitation channels
  • Two binary inputs
  • Four control outputs
  • One 5 Vdc power terminal
  • One 12 Vdc power terminal
  • One a serial I/O port.