manufacturer :       Radiometer

model :                   PHM 250

annotation :           Dokumente engl.

The PHM250 lon Analyzer is a key Instrument in MeterLabN, the com­ plete range of measuring equipment for accurate and reliable pH, Ion and conductivity measurements from RADIOMETER. The PHM250 cornbines advanced features with user convenience making it equaily suitable for both high-precision and routine ion concentration analysis. The versatile PHM250 is also ideal for performing pH and mV measure­ ments.

Ion concentration, pH and mV measurement methods can be individu­ ally edited to fit your specific talks. The PHM250 offers 16 methods, each containing all the information necessary for your application: electrode type, calibration procedure etc. The method link facility and the two electrode Inputs makes it easy for you to perform two different measurements in the same sample. For each method, up to 9 sample measurements and 9 calibration results are stored in the GLP table.

Ion concencentration measurements can be performed directly, based on a calibration with up to 9 calibration points, or by using one of the tour addition techniques. Up to 9 additions can be made during a standard addition or standard subtraction measurement and an analate addition

or analate subtraction measurement.

Using AUTOREAL, the pH, mV or direct ion concentration reading is Iocked on the display as soon as the stability criterion and/or the accept time are reached, ensuring excellent repeatability. Measurements can also be performed continuously and printed out at specific time intervals.

Three pH calibration modes are available: AUTO recognition of I1JPAC, TECHNICAL or RADIOMETER Series buffers, FREE adjustment of the buffer value or use of FIXED buffer values.

Instead of using just two buffer sofutions for your calibration, the PHM250 can perform a calibration with up to 9 buffer solutions. The calibration resulting from this linear regression is ideal for high-precision pH measurements.

The PHM250 can be connected to a sample changer for unattended sample batch analysis. In addition, it has built-in Interfaces for printer/PC and a recorder.

Specifications

Measuring ranges:                       pH: -9.000 to +23.000

                                                    mV: -1999.9 to +1999.9

                                                    °C:   -9.9 to +99.9

                                                    Conc.: 0.001 x 10 ^-9 to 999.9x 10 ⁹

Resolution:                                   pH: 0.001 pH

                                                    mV: 0.1 mV

                                                    °C: 0.1 °C

                                                    Conc.: 0.5% for monovalent ions after calibration;

                                                    1% for divalent ions

Accuracy:                                     pH: ±0.002 pH

                                                    mV : ±0.1 mV or ±0.1 %

                                                    Conc.: ±0.5% for monovalent ions after calibration;

                                                    ±1% for divalent ions

                                                    °C: ±0.5 °C

Electrode Inputs:                          Combined/glass, ion selective

                                                    electrode (2 x BNC)

                                                    Reference electrode (2 x banana)

                                                    Temperature sensor (CINCH)

Electrode Input resistance:         > 2 x 10 ¹² Ω

Terminal current:                         < 0.5 pA at 25 °C ambient

Measurernent modes:                  pH, mV and ion concentration

Measurement procedures:          pH, mV an d concentration reading with

                                                    sliding stability indicator

AUTOREAD pH, mV and concentration: the result is locked an the display when the user-selected stability criterion and/ or accept time are reached

Standard additionlsubtraction and

Analate addition/subtraction meas­urements can be performed with up to 9 additions. The user will be prompted to make the addition after the neeswe­rnent has been accepted

                                                    pH/mV/conc . reading and printing at set intervals

Min. and max. alarms can be set for pH, mV, concentration and temperature

pH Calibration:                             One, two or multiple-point (up to 9) calibration

                                                    AUTO recognition of buffers:

                                                    IUPAC buffers (DIN19266):

                                                    pH 1.68, 4.01, 7.00, 10.01 and 12.45 or

                                                    Technical buffers (DIN 19267):

                                                    pH 1.09, 4.65 and 9.23 or

                                                    RADIOMETER Series pH 4 - 7 - 10 at 25°C

                                                    Calibration with FIXED buffers selected   -

                                                    from the above buffers and IUPAC pH 3.56, 6.86, 7.41

                                                    and 9.18

                                                    FREE entry of the buffer value

ISE calibration:                             One, two or multiple-point (up to 9)

calibration . E°, sensitivity and blank value are determined from the non linear calibra­tion curve.

The electrode sensitivity will be determined during a two (or more) addition/subtraction measurement.

Concentration units:                     mol/L, mmol/L, p.mol/L, g/L, mg/L, M, mM, % and ppm

Electrode requirements:              Sensitivity: 95 % to 102 %

(Autocal)                                       Zero pH: pH 5.800 to 7.500

Data storage:                               16 methods each with Parameters for

                                                    sample measurements and calibration procedures

Method link:                                  Two methods can be linked

GLP Functions:                            Complete printouts with date, time, instrument ID and,

                                                    if selected, calibration data used

                                                    Last 9 calibration results

                                                    Last 9 sample results for each method

Display:                                        2 x 16 character , alphanumeric LCD display

Languages:                                  English/French or EnglishlGerman

                                                    depending an the version of your PHM250

Inputs/Outputs:                            RS232C insulated !Dort for connection of

                                                    printer or PC

RS232C port for connection of the
SAC80 or SAC90 sample changer

                                                    Analogue recorder ouput

Ambient temperature:                  5 to 40 °C

Relative humidity:                         20 to 80 %

Power requirements:                   115/230 V -18/+15 %

                                                    47.5 to 63 Hz, 8 VA

Fuse regufretrients:                     Main Fuse: type: T100mA L250 V

                                                    UL recognised

Secondary fuses (not to be replaced by the user): 500 mA type picofuse , UL recognised

Finish:                                          Chemical resistant, splashproof cabinet

Weight:                                         1.9 kg

Dimensions (H x W x 0):             8 x 28.5 x 20 cm