Section 6: Diagnostics & Troubleshooting

396P + 396PVP Sensors Instruction Manual

August 2013

LIQ_MAN_396P_396PVP

 

 

6.2Troubleshooting without Advanced Diagnostics

Table 7-2, below, lists common problems, causes and remedies typically encountered in process measurement.

TABLE 6-2. Troubleshooting without Advanced Diagnostics

Problem

Probable Cause

Remedy

 

 

 

Meter reads off scale. (Display

Defective preamplifier

Replace preamplifier (for code 02

reads overrange).

 

sensors). For code 01, replace sensor.

 

 

 

 

T.C. element shorted

Check T.C. element as instructed

 

 

in Section 6.1 and

 

 

replace sensor if defective.

 

 

 

 

Sensor not in process. Sample

Make sure sensor is in process with

 

stream is low or air bubbles are

sufficient sample stream (refer to

 

present.

Section 2.0 for installation details).

 

 

 

 

Open glass electrode

Replace sensor.

 

 

 

 

Reference element open - no contact

Replace sensor.

 

 

 

Display reads between 3 and 6 pH

Electrode cracked

Replace sensor.

regardless of actual pH of solution

 

 

or sample.

 

 

 

 

 

Meter or display indication swings

T.C. element shorted

Check T.C. element as instructed

or jumps widely in AUTO T.C. Mode.

 

in Section 6.1 and replace

 

 

sensor if defective.

 

 

 

Span between buffers extremely

T.C. element open

Check T.C. element as instructed

short in AUTO T.C. Mode.

 

in Section 6.1 and replace sensor

 

 

if defective.

 

 

 

Sluggish or slow meter indication

Electrode coated

Clean sensor as instructed in

for real changes in pH level.

 

Sections 6.2 or Section 6.3.2.

 

 

Replace sensor if cracked.

 

 

 

 

Electrode defective

Replace sensor.

 

 

 

Transmitter cannot be standardized.

Electrode coated or cracked

Clean Sensor as instructed in

 

 

Sections 6.2 or Section 6.3.2

 

 

Replace sensor if cracked.

 

 

 

 

Defective preamplifier

Replace preamplifier.

 

 

 

Transmitter short spans between

Aged glass electrode or high

Replace sensor.

two different buffer values.

temperature exposure

 

 

 

 

 

Electrode coated

Clean Sensor as instructed in

 

 

Section 6.2 or Section 6.3.2.

 

 

Replace sensor if cracked.

 

 

 

 

Air bubbles trapped in sensor end

Shake the sensor in solution. See

 

between glass bulb and sensor body

Section 2.0 for mounting guidelines.

 

 

 

42

Diagnostics and Troubleshooting

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Emerson 396PVP instruction manual Troubleshooting without Advanced Diagnostics, Diagnostics & Troubleshooting