Key features of the 875CR are summarized below:

• Dual sensor input
• High accuracy and wide rangeability
• USP23/24 compliant for pharmaceutical applications
• Single unit for either conductivity or resistivity
• Compatible with Foxboro 871CR and 871CC sensors
• Application switching and storage of up to 3 sets of application configurations
• Remote range and application switching using PLC compatible contact inputs
• History log for up to 100 time and date stamped events
• Resistivity system accuracy of +/- 1.06% RMS

• The 873CC analyzer is an economical, basic, line-powered contacting conductivity analyzer in a small form factor.
  
  Each 873CC analyzer provides up to two contacting conductivity sensor inputs, two analog output signals (one on plastic version) (4-20 mA, 0-10 V, 0-20 mA), and two alarm relays.
  
  A choice of plastic, panel-mount or metal, field-mount enclosure is available. Each enclosure is ¼ DIN. The metal enclosure is rated NEMA 4X, while the plastic enclosure is NEMA 12 from the front and NEMA 1 from the rear.
  
  The 873CC offers several standard ranges from 0 to 1 uS/cm up to 0 to 20 mS/cm. It is used with 0.1 cm-1 cell factor sensors for low conductivity ranges and with 10 cm-1 cell factor sensors for ranges above 200 uS/cm.
  
  When operating in dual sensor mode, the analyzer must be connected to two sensors of the same cell factor (either both 0.1 cm-1 or both 10.0 cm-1). When two sensors are connected, the analyzer can either report two measurements independently or can be configured to compare the two cells and report in units of % rejection or ratio.
  
  873CC analyzers are compatible with 871CC series sensors.

    The 873ARS analyzer is Foxboro’s most economical solution for

    basic resistivity analysis. The 873ARS is line-powered.

     Each 873ARS analyzer provides a single resistivity sensor input,

    one analog output signal (4-20 mA, 0-10 V, 0-20 mA), and two

    alarm relays.

     As compared to the 873RS analyzer, the configuration menus

    in the 873ARS are simplified and there is no lock/unlock function.

    The 873ARS analyzer provides a single sensor input and single

    analog output, whereas the 873RS provides two of each.

     A choice of plastic, panel-mount or metal, field-mount enclosure

    is available. Each enclosure is ¼ DIN. The metal enclosure is

    rated NEMA 4X, while the plastic enclosure is NEMA 12 from the

    front and NEMA 1 from the rear.

     The 873ARS offers a single measurement range of 0 to 20 Moh

    m•cm.

     873ARS analyzers are compatible with 871CC series sensors.

    The 871CC sensor must have a cell factor of 0.1 cm-1 to operate

    with the 873ARS analyzer.

• The 871CR sensors are high performance, precision probes used for measurements ranging from ultrapure water (18+ M ohm•cm) through pure water and up to water supplies with conductivity values as high as 20 mS/cm.
  
  Two cell factors are offered, 0.1 cm-1 and 10 cm-1. The 0.1 cm-1 types are used for resistivity measurements and any conductivity measurements below 200 uS/cm. They are offered with either titanium or monel electrode materials. The 10 cm-1 types are used for higher conductivity measurements above 200 uS/cm, and employ graphite electrodes covered with a removable metal sheath.
  
  For pure and ultrapure water measurements, the 871CR sensors provide the highest possible accuracy. Each 0.1 cm-1 sensor is individually characterized and labeled with a 0.1% accurate cell factor value. The built-in temperature sensor is a high accuracy, 3-wire, 1000 ohm platinum RTD. The threaded bushing material is plastic to resist temperature offsets caused by swings in ambient temperature.
  
  Several mounting styles are available, including threaded bushing (3/4 inch and 1 inch NPT), Tri-clamp sanitary, universal with O-ring seal and retractable with a ball valve or gate valve assembly. The universal bore piece mounting design prevents cable wind-up during installation and removal. Several mounting accessories are also offered, including flow chambers, threaded bushings and flanges. For optimized sampling, the 871CR sensors are provided in several different insertion lengths.
  
  The 871CR sensors are compatible with 875CR analyzers and 870ITCR transmitters. They are not compatible with 873CC, 873RS, 873ACC or 873ARS analyzers.
  
  

• The 871CC sensors are basic, economical probes used for measurements ranging from ultrapure water (18+ Mohm•cm) through pure water and up to water supplies with conductivity values as high as 20 mS/cm.
  
  Two cell factors are offered, 0.1 cm-1 and 10 cm-1. The 0.1 cm-1 types are used for resistivity measurements and any conductivity measurements below 200 uS/cm. They are offered with either titanium or monel electrode materials. The 10 cm-1 types are used for higher conductivity measurements above 200 uS/cm, and employ graphite electrodes covered with a removable plastic sheath.
  
  For low and moderate temperature applications, a built-in 100 Kohm thermistor is used for automatic temperature compensation. For high temperature applications, a 100 ohm RTD is available and is recommended.
  
  Several mounting styles are available, including threaded bushing (3/4 inch NPT), twist-lock, Tri-clamp sanitary, universal with O-ring seal and retractable with a gate valve assembly. Several mounting accessories are also offered, including flow chambers, threaded bushings and flanges.
  
  The 871CC sensors are compatible with 875CR, 870ITCR, 873CC, 873RS, 873ACC, 873ARS and several older Foxboro analyzers and transmitters.