Start Up And Calibrate - Emerson Rosemount 396P Quick Start Manual

November 2020
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Start up and calibrate

3.1 Calibrate Rosemount 396P and 396PVP pH sensors
3.1.1 Prepare sensor
Procedure
1. Shake down the sensor to remove any air bubbles that may be
present at the tip of the pH glass bulb.
2. To obtain greater accuracy or to verify proper operation, calibrate
the sensor as a loop with its compatible transmitter.
3.1.2 Calibrate pH
1. Establish a temporary connection between the sensor and the
transmitter.
2. Perform a buffer calibration.
3. Consult the appropriate pH/ORP transmitter Reference Manual for
specific calibration and standardization procedures, or see
with two buffer solutions
calibration procedure.
Calibrate with two buffer solutions
Prerequisites
Select two stable buffer solutions, preferably pH 4.0 and 7.0. (You can use
pH buffers other than pH 4.0 and pH 7.0 as long as the pH values are at least
two pH units apart).
Note
A pH 7 buffer solution reads an mV value of approximately zero, and pH
buffers read approximately ±59.1 mV for each pH unit above or below pH 7.
Check the pH buffer manufacturer specifications for millivolt values at
various temperatures, as it may affect the actual value of the buffer solution
mV/pH value.
Procedure
1. Immerse the sensor in the first buffer solution. Allow the sensor to
adjust to the buffer temperature (to avoid errors due to temperature
differences between the buffer solution and sensor temperature) and
wait for readings to stabilize.
The transmitter can now acknowledge the value of the buffer.
2. Once the first buffer has been acknowledged by the transmitter,
rinse the buffer solution off the sensor with distilled or deionized
water.
Quick Start Guide
for the recommended two-point buffer
Quick Start Guide
Calibrate
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