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10

8860 Dual Channel Conductivity/Resistivity Controller 

TDS Factor

Some industries need to display a conductivity value as Total 
Dissolved Solids (TDS), measured in units of parts per million  
(PPM) or parts per billion (PPB).
•  1 PPM is equivalent to 1 mg per liter.
•  1 PPB is equivalent to 1 

μ

g per  liter.

•  The 8860 calculates PPM or PPB by dividing the 

μ

S value 

by a TDS Factor that you de

fi

 ne.  TDS factors can vary 

widely, ranging from 1.50 to 2.50 

μ

S per PPM.  Methods 

for establishing a TDS factor are beyond the scope of this 
manual.

•  The 8860 will accept TDS factor values from 0.01 to 99999.9 

μ

S per PPM.

 

(factory preset = 2.00 

μ

S per PPM)

NOTE:  The 8860 TDS factor must be set in PPM.   

TDS Factor  = Conductivity (

μ

S) ÷Total dissolved solids (PPM) 

PPM  = Solution conductivity (

μ

S)  ÷ TDS Factor

Example:
•  Solution conductivity = 150 

μ

S

•  TDS = 80 PPM
•  TDS Factor =   

150 

μ

S ÷ 80 PPM   = 

1.88 

μ

S per 

PPM

 

 

 

Temperature Effects

Conductivity measurement is highly dependent on temperature.  
The basic rule is that higher temperatures result in greater 
conductance (less resistance).
Temperature effects are expressed as the percentage of 
conductivity change (in 

μ

S) per °C.  The conductivity value is 

generally referenced to 25ºC.  The 8860 has three temperature 
compensation options:

None

USP standards for pharmaceutical waters require that the 
measurement be made without temperature compensation.  USP 
limits are discussed on page 7.

Pure Water (Standard Compensation)

This selection is used for measurements of very clean water, 
less than 0.2 

μ

S.  Temperature effects are not linear in this 

range, so the temperature coef

fi

 cient is not easily determined.  

This selection is recommended for all Resistivity applications 
measuring from 5 M

Ω

 to 18M

Ω

.  This selection conforms to ASTM 

standard D1125 and D5391.

Linear

This selection allows you to calculate a custom temperature 
compensation value for Conductivity measurements in the range 
of 0.2 

μ

S and greater (Resistivity applications measuring less 

than 5 M

Ω

).  The procedure is outlined in the section on  the right.

Calculating a Linear Temperature Coef

fi

 cient

1.

  Set TC Mode to NONE (see OPTIONS menu, page 8).

2.

  Heat a sample solution close to the maximum process 

temperature.  Place sensor in the sample solution and 
allow several minutes for stabilization.  Record the 8860 
temperature and conductivity values in the spaces provided:

 

Displayed temperature: 

T1 = _______ °C

 
 

Displayed conductivity: 

C1 = _______ 

μ

S

3.

  Cool the sample solution close to the minimum process 

temperature.   Place sensor in the sample solution allowing 
several minutes for stabilization.  Record displayed 
temperature and conductivity values in the spaces provided:

 

Displayed temperature: 

T2 = _______ °C

 
 

Displayed conductivity: 

C2 = _______ 

μ

S

 

(A 10% change in conductivity between steps 2 and 3 is 
recommended.)

4.

  Substitute recorded readings (steps 2 and 3) into the following  

 formula:

  TC Slope =                   100 x (C1 - C2)              
   

(C2 x (T1 - 25)) - (C1 x (T2 - 25))

Example:  A sample solution has a conductivity of 205 

μ

S @ 

48°C.  After cooling the solution, the conductivity was measured 
at 150 

μ

S @ 23°C.  (C1 = 205, T1 = 48, C2 = 150, T2 = 23) 

The TC is calculated as follows:  

TC Slope =                 100 x (205 - 150)             =5500 = 1.42%/°C
 

(150 x (48 - 25)) - (205 x (23 - 25))  3860

Содержание 8860

Страница 1: ...00 to 240 VAC 10 50 60 Hz 20VA or 11 to 24 VDC 10 regulated 0 5 A max 3 8860 11 to 24 VDC 10 regulated 0 5 A max Three 4 to 20 mA Outputs Passive isolated fully adjustable and reversible 4 to 20 mA outputs are independently source selectable Max loop impedance 150 Ω 12 V 450 Ω 18 V 750 Ω 24 V Update rate 100 mS Accuracy 0 03 mA 25 C 24 VDC Open collector outputs 2 available optically isolated 50 m...

Страница 2: ...not insert two wires into a single terminal If necessary splice the wires together before inserting into the terminal RELAY 1 RELAY 2 RELAY 3 RELAY 4 N C N O COM N C N O COM N C N O COM N C N O COM RELAY 3 4 OPEN COLL 3 4 OPEN COLL 4 OPEN COLL 4 OPEN COLL 3 OPEN COLL 3 LOOP 2 LOOP 2 LOOP 3 LOOP 3 LOOP 1 LOOP 1 SHLD ISO GND TEMP 1 SGNL 1 SHLD ISO GND TEMP 2 SGNL 2 POWER OUTPUT OPTION L N 11 24V 0 5...

Страница 3: ...e process condition The maximum pulse rate is 400 pulses per minute Example As the process falls below 10 μS the output will start pulsing in relation to the process value the max pulse endpoint and the programmed pulses min Pulse rate will increase as the process approaches the programmed endpoint SHLD ISO GND TEMP 2 SGNL 2 SHLD ISO GND TEMP 1 SGNL 1 RED WHITE BLACK SILVER SHLD RED WHITE BLACK SI...

Страница 4: ...n Signet Conductivity Resistivity Transmitter C1 23 45µS C2 8 72µS Relay 1 Relay 2 ENTER VIEW menu During normal operation the ProcessPro displays the VIEW menu When using the CALIBRATE or OPTIONS menus the ProcessPro will return to the VIEW menu if no activity occurs for 10 minutes To select the item you want displayed press the UP or DOWN arrow keys The items will scroll in a continuous loop Cha...

Страница 5: ... UP DOWN keys in sequence After entering the Key Code the display will show the first item in the selected menu Step 3 Scroll menu with UP or DOWN arrow keys Step 4 Press RIGHT ARROW key to select menu item to be edited The first display element will begin flashing Step 5 Press UP or DOWN keys to edit the flashing element RIGHT ARROW key advances the flashing element Step 6 Press ENTER key to save...

Страница 6: ...onitored by Relay 1 Cond 1 Cond 2 Temp 1 Temp 2 Function Set Relay 1 activation point The maximum value acceptable is 999999 USP setpoints are high alarms where the setpoint is a percentage below the USP limit Relay 1 will be deactivated at setpoint Hysteresis depending on High or Low selection When the relay Mode is USP defined as a HIGH alarm Hysteresis is displayed in μS Set up to 6400 seconds ...

Страница 7: ... based on the measured temperature Using the USP function In the 8860 USP setpoints are defined as a percentage below the USP limit so a USP alarm is always a HIGH alarm The 8860 can be set to warn you if the conductivity approaches within a set percentage of the USP limit The following settings and conditions are required for a USP relay function 1 In the CALIBRATE menu RELAY MODE must be set to ...

Страница 8: ... 8 sec averaging if your process experiences frequent or extreme fluctuations Set the decimal to the best resolution for your application The display will automatically scale up to this restriction Select or Adjust the minimum and maximum current output The display value represents the precise current output Adjustment limits 3 80 mA 4 00 mA 5 00 mA 19 00 mA 20 00 mA 21 00 mA Use this setting to m...

Страница 9: ...onductivity Siemens 0 000020 Siemens Conductivity Sensor cell e g 0 1 Cell 0 000001 Siemens Simulation resistance Ω 100 000 Ω or 1μS cm 1 μS 1 X 10 6 Siemens or 0 000001 Siemens Connect the conductivity resistor between the Sgnl 1 and Iso Gnd or Sgnl 2 and Iso Gnd terminals Set Cond Adjust the conductivity value based on the resistor value See Editing Procedure and Calibrate menu Verify the linear...

Страница 10: ...lean water less than 0 2 μS Temperature effects are not linear in this range so the temperature coefficient is not easily determined This selection is recommended for all Resistivity applications measuring from 5 MΩ to 18MΩ This selection conforms to ASTM standard D1125 and D5391 Linear This selection allows you to calculate a custom temperature compensation value for Conductivity measurements in ...

Страница 11: ...mal setting in OPTIONS menu Check Calibrate menu settings for incompatible SOURCE and RANGE values Select a value from 0 to 100 Select a value greater than zero Select a pulse rate less than 400 This will remove any user calibration from the Set Conductivity and Set Temperature items in the Calibrate menu Check calibration procedure for accuracy Check sensor for proper operation Check any cable ex...

Страница 12: ...n Certified 3 2819 T2 159 000 082 CR Sanitary 0 01 Titanium 2 in 3 2819 T2C 159 000 084 CR Sanitary 0 01 Titanium 2 in Certified 3 2820 S1 159 000 089 CR Sanitary 0 1 SS 1 to 1 1 2 in 3 2820 S1C 159 000 091 CR Sanitary 0 1 SS 1 to 1 1 2 in Certified 3 2820 S2 159 000 090 CR Sanitary 0 1 SS 2 in 3 2820 S2C 159 000 092 CR Sanitary 0 1 SS 2 in Certified 3 2820 T1 159 000 624 CR Sanitary 0 1 Titanium ...

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