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  • Direct reading of % RH eliminates the need for look up tables and lengthy calculations
  • Wet bulb / Dry bulb sensing allows for the device's use in elevated ambient conditions and/or dirty installations
  • Compensates for changes in barometric pressure and differences in temperature
  • RS-485 communications option
  • Security lockout of keypad prevents unauthorized or accidental changes
  • Available as a dual pen recording controller or recording profile controller
  • 24V DC transmitter power supply for use with mA DC input provides additional flexibility
  • UL, CE, and CSA approvals ensures standards of quality and performance
  • This model complies with Section 1065 of ARRA-09 requirements


The 10" microprocessor-based Partlow MRC 7700 circular chart recorder is capable of measuring, displaying, recording, and controlling relative humidity and/or temperature using Dry Bulb and Wet Bulb temperatures from a variety of inputs. With its automatic calculation feature, the Partlow MRC 7700 circular chart recorder eliminates the need to use charts, graphs, and arithmetic to manually figure relative humidity.

The Partlow MRC 7700 circular chart recorder uses a special algorithm to calculate relative humidity and compensate for barometric pressure changes and temperature differences, which increases accuracy and saves time. Using the wet-bulb/dry-bulb sensing rather than a humidity sensor, the Partlow MRC 7700 circular chart recorder operates efficiently and accurately even in elevated ambient temperatures and dirty environments that normally harm humidity sensors.

Partlow MRC 7700 circular chart recorders also offer many valuable features including auto transfer, position proportioning output, remote setpoint, remote run/hold, auto/manual operation, and setpoint lock-out. Other features of the Partlow MRC 7700 circular chart recorder include output limiting, ten-inch circular chart, displays for each process value, no DIP switches, full parameter programming with large tactile keys, up to six-events, and relay outputs or SSR drivers. Two alarms per channel (process/deviation/deviation band reverse or direct), eight profiles with six ramp/soak segments each, and process value retransmission are also featured on the Partlow MRC 7700 circular chart recorder.

In addition, the Partlow MRC 7700 circular chart recorder has a security enable mode system feature which protects all parameters and data from unauthorized changes. Each version may be specified with an RS-485 communications option for easy access to process variables via your computer.

Applications for the Partlow MRC 7700 Circular Chart Recorder

The Partlow MRC 7700 circular chart recorder's control, recorder, and security functionality are designed specifically for Relative Humidity applications including:

  • Process validation and trend analysis
  • Relative humidity

Appropriate industries for the Partlow MRC 7700 circular chart recorder include oven, chamber, furnaces, heat treating, food processing, and harsh water environments.



Please consider these optional accessories.


Standard Zero Based Charts

Standard Non-Zero-Based Charts

Reverse Range Charts

Dual Range Charts

Charts with No Numbers on Divisions

Unique Range Charts