Emerson 381 User Manual

Meter reads off scale.

Reference electrolyte depleted.

Replace reference electrolyte as
instructed in Section 3.2.2.

Defective preamplifier.

Check preamplifier as instructed in 
Section 3.4 and replace 
preamplifier if defective.

T.C. element shorted.

Check T.C. element as instructed in 
Section 3.5, and replace body if 
defective.

Electrode not in solution or sample 

Make sure sensor is in solution or that

stream is not full.

sample stream is full (refer to Section 
2.0 for installation details).

Open glass electrode.

Replace glass electrode.

Plugged liquid junction.

Replace liquid junction. 
Recharge reference cell.

Reference element open-

Replace reference element.

no contact.

Meter reads between 3 and 6 pH

Electrode cracked.

Replace electrode.

regardless of actual pH of 
solution or sample.

Meter indication swings widely 

T.C. element shorted.

Check T.C. element as instructed in 

in AUTO T.C. Mode.

Section 3.5 and replace body if 
defective.

Span between buffers extremely 

T.C. element open.

Check T.C. element as instructed in 

short in AUTO T.C. mode.

Section 3.5 and replace body if 
defective.

Sluggish or slow meter indication 

Electrode coated.

Clean electrode as instructed in

for real changes in pH level.

Section 3.2.1.

Electrode defective.

Replace electrode.

Transmitter cannot be 

Electrode coated or cracked.

Clean electrode as instructed in 

standardized.

Section 3.2.1 and, if cracked, 
replace electrode.

Reference chamber is contaminated 

Replace gel solution as 
instructed in Section 3.2.2.

Defective preamplifier.

Check preamplifier as instructed in 
Section 3.4 and replace if 
defective.

If trouble still persists, micro-junction 

Replace micro-junction electrode.

electrode is defective.

Meter short spans.

Old glass electrode (greater than 1 

Replace electrode.

year use).

Coated glass.

Clean with soft cloth and clean water.