10
2850 Conductivity/Resistivity Sensor Electronics
Signet offers conductivity simulators in
fi
ve different values. These tools enable the user to validate the performance of the
electronics independently of the electrode. This requirement is de
fi
ned by ASTM D 1125-95 (Standard Test Methods for Electrical
Conductivity and Resistivity of Water) which is commonly used for USP 24 applications.
3-2850.101-1 (159 001 392)
1.0
μ
S ±0.1%
3-2850.101-2 (159 001 393)
2.5
μ
S ±0.1%
3-2850.101-3 (159 001 394)
10.0
μ
S ±0.1%
3-2850.101-4 (159 001 395)
18.2 M
Ω
±0.1%
3-2850.101-5 (159 001 396)
10.0 M
Ω
±0.1%
Before using the Simulator:
Before using the simulators, disconnect all electrodes and reset the 2850 Electronics to factory calibration:
1. Set all switches on SW3 (and SW4 for Dual Input) to OPEN. Turn the power on, wait at least 3 seconds
2. Press and hold SW1 until the LED (D3) comes on steady then goes off again (approx. 10 seconds).
3. When the LED goes off, release SW1. Reset is complete.
To validate Input 1:
1. Turn the power off.
2. Set SW3 to accept a 0.01 cell constant. Leave SW4 in the all-OPEN position.
3. Install the simulator into the 2850 at the Input 1 conductivity electrode terminals.
4. Connect the 2850 output terminals to the appropriate display instrument. Turn the power on.
• The display should indicate a conductivity value within ±2% of the simulator value.
• If the output is x10 or x100 of the correct value, recheck step 2. The 2850 is not set to accept a 0.01 cell constant.
• If the correct value is displayed, the electronics are calibrated to ASTM D 1125 speci
fi
cations. Remove the simulator and
reset SW3 to the correct cell constant before reinstalling the electrode.
• If the correct value is not displayed, contact the factory.
To validate Input 2:
1. Turn the power off.
2. Set SW4 to accept a 0.01 cell constant.
3. Install the simulator into the 2850 at the Input 2 conductivity electrode terminals.
4. Set SW3 switches to the all-OPEN position.
5. Turn the power on and repeat step 4.
Remember
to reset all switches to their correct position before resuming normal operation.
Cond. - Resist.
Simulator
@ 25°C
For use with Signet
2850 Conductivity
NIST Traceable
Electronic Certi
fi
cation
