Jenway 3540 - Manual (Page 71)

8.4 Troubleshooting - Conductivity
Fault
Possible Cause Action
No display
Check power supply Check that correct 9V ac
power supply is connected and switched
on
Erratic display
Check power supply The 3540 must be used with the
supplied 9V ac power supply
The 3540 will not operate with other
power supply units
Unstable display
Conductivity cell Replace conductivity cell
defective
Display permanently Intermittent or no Check cell connection to 3540
under or over range connection
Conductivity cell defective Replace conductivity cell
Contaminated solutions Replace solutions
Intermittent display
Conductivity cell not Check connections
fitted correctly
Reading drifts
Conductivity cell stored dry Allow to soak for 2 hours
CO
2
absorption by sample Noticeable for low conductivity
- do not allow sample to stand in
unstoppered bottles
Non linear readings Conductivity cell not zeroed Zero conductivity cell
Poor reproducibility
Carryover between Rinse cell in distilled water
solutions between measurements
Will not print
IrDA connection broken Line up units or use the supplied
RS232 connector
Paper out The feed light on the printer will
flash if the unit requires paper
Battery flat Connect ac power supply
8.5
Functional Check – pH
The pH measurement function of the meter can be checked using the enclosed BNC shorting
cap (009 146).
1.
Remove the ATC probe, if connected.
2. Set the manual temperature compensation to 25°C.
3. Remove the pH electrode and replace it with the BNC shorting cap.
4. Select the mV mode. The display should read ±1.
If the mV reading is greater then ±1mV perform a reset (refer Section x.x)
To make a measurement from this point, refit the ATC probe and pH electrode and calibrate
the 3540 using fresh buffer solutions.