C-52 Sample Chamber

Wescor's sample chamber, model C-52, can measure the water potential of solutions, small soil or leaf samples, and leaf discs. Due to the solid aluminum housing, the C-52 provides highly accurate water potential measurements without the need for a constant temperature bath.

The C-52 must be connected to a Wescor water potential instrument such as the PSYPRO, HR-33T, or CR7 for operation.

The Sample Chamber measures water potential of small samples in the laboratory or in the field without requiring a constant temperature bath.  A precision thermocouple transducer in an internal chamber functions either as a psychrometer (wet bulb depression method), or as a hygrometer (dew point depression method) depending upon the type of readout equipment employed.  Researchers have reported exceptional ease and accuracy using this chamber, resulting in more and better data from field and/or laboratory research.

The instrument is precision machined and expertly assembled to assure accuracy and precise operation.  Each unit is individually performance tested before leaving the factory.

An all-metal thermocouple mount provides direct thermal contact between the thermocouple and the upper heat sink.  This and the solid aluminum housing give more rapid temperature equilibration and reduced zero offset error.

A copper-constantan temperature sensor allows accurate chamber temperature measurements to be made for correction of psychometric readings for Pv temperature correction when large temperature changes are encountered.

Wescor's sample chamber model C-52


  • Measuring total water potential of soil or plant tissue
  • Measuring relative vapor pressure of organic solvent solutions (alcohol, acetone, carbon tetrachloride, toluene, benzene, etc.)
  • Multiple C-52 chambers can be connected to the CR-7 Datalogger to function as an automated multichannel osmometer
  • As an osmometer, can do rapid, accurate sampling without freezing (10 microliter samples)
Wescor's sample chamber, model C-30



Dimensions:              Approximately 57 mm diameter x 75 mm height

Weight:                     Approximately 0.45 kg

Lead Length:            1.5 m

Sample Holders:       6 holders furnished (2 of each size):

                                 9.5 mm diameter x 4.5 mm deep for soil or other large samples

                                 7 mm diameter x 2.5 mm deep for leaves

                                 7 mm diameter x 1.25 mm deep for saturated filter paper disks

Range:                      -0.05 MPa to -8 MPa nominally

Calibration:               By standard solutions

Process Time:           30 seconds up to several minutes, depending upon time required for sample to reach

                                 vapor equilibration

Precision:                  0.01 MPa ±2%

SUREFAST connector option available (specify C-52-SF)

C-30 Sample Chamber

Wescor's C-30 sample chamber is made from modified stainless steel tube fittings and a PST-55-15 thermocouple psychrometer/hygrometer. The sample chamber is large enough to accommodate an entire small leaf or a significant portion of larger leaves. The stainless steel fittings and O-rings provide a positive seal. The chamber can be immersed in a temperature bath or insulated box to ensure good temperature stability. If interested in osmotic potential of leaves, the entire chamber can be immersed in liquid nitrogen to freeze and breakdown leaf cellular structure.

The C-30 Sample Chamber is designed to be used with the HT-33T Dewpoint Microvoltmeter or the Wescor/Campbell CR-7 Datalogger.


Dimensions:Approximately 25 mm diameter x 50 mm height
Weight:Approximately 0.45 kg
Lead Length:1.5 m
Sample Size:Approximately 1 cm3 soil, leaf, solution sample
Range:-0.05 MPa to -8 MPa nominally
Calibration:By standard solutions
Process Time:30 seconds up to several minutes, depending upon time required for sample to reach vapor equilibration
Precision:0.01 MPa ±2%

SUREFAST™ connector option available (specify C-30-SF)

When used with the PS-10 a SUREFAST™ connector is required.  The HR-33T or Wescor/Campbell system can be used with or without the SUREFAST™ connector.