GF Signet 2759 pH-ORP System Tester - Manual (Page 2)

2 Signet 2759 pH/ORP Simulator and System Tester
Step 4: Check the meter and preamplifi er
Connect 2759 as in "B"
• Connect the 2759 directly into the meter using the bypass
adapter cable.
• Connect a 3 KΩ resistor (not supplied) to the temp input of
the meter.
• Press output simulation buttons.
Does the meter display a valid temperature (20 ºC to 30 ºC)
and pH/ORP?
Yes: If there are no cable junctions from the preamplifi er to the
meter, replace the preamplifi er. If there are junctions, go to
next step.
No: Problem is in meter. Repair or replace the meter.
Step 5: Check interconnecting cable and junctions
• Connect 2759 and bypass cable at any J-Box or cable splice
between the preamplifi er and the meter.
• Press output simulation buttons.
See Section 5: Response chart for proper display
Does the meter read valid temp and pH/ORP?
Yes: Problem is preamplifi er or cable from preamplifi er to junction.
No: Problem is in cable.
Check all terminals and splices. Replace cable if necessary.
3. Troubleshooting ProcessPro, ProPoint, and
2760 Preamplifi er
Step 1: Routine maintenance and calibration using buffers
• The most common problem in pH or ORP systems are related
to electrode depletion or physical obstruction and fouling.
• Perform routine electrode maintenance, including cleaning and
inspection of the electrode, then calibrate the system using
buffer solutions. See the electrode and 2760 Preamplifi er
manuals for more information.
Does the meter respond to buffers correctly?
Yes: Problem resolved by cleaning/calibration.
No: Go to next step.
Connecting the 2759 output to the
3-2759.391 adapter cable then
connecting to the 2760 preamplifi er
simulates the output of the pH/ORP
electrode.
This confi guration is used to verify
general system operation. Every
element of the system is tested except
the electrode.
Step 2: Electrode
Connect 2759 as in "A"
This step requires the 3-2759.391 adapter cable.
• Connect the 2759 to the appropriate adapter cable, then insert
adapter into 2760 preamplifi er.
• Slide the Mode selector switch to the proper position.
• Press output simulation buttons and then HIΩ button.
(The
HIΩ button must be pressed after each output button.)
• See Section 5: Response Chart for proper display
Does the meter read valid temp and pH/ORP?
Yes: The electrode is at fault. Replace the electrode.
No: Go to next step.
Step 3: Verify meter calibration
• Recalibrate the temperature, standard and slope in meter, using
2759 as input.
• Press output simulation buttons.
See Section 5: Response chart for proper display
Does the meter display valid pH or ORP?
Yes: Problem resolved by meter calibration.
No: Go to next step.
Connecting the 2759 directly to the meter with the 3-2759.390
Bypass cable simulates the output of the 2760 preamplifi er.
B
A
• Press any output simulation button to
turn the 2759 on.
• Press OFF button to turn the 2759 off.
• Press any output simulation button to
turn the 2759 on.
• Press OFF button to turn the 2759 off.
1K
ORP 10K
3K
Silver (earth ground)
(mV input) (iso. ground) (V
-)
(V+) (T+) (T
-)
Brown Blue Green White Red Black
Brown Blue Green White Red Black
Silver (earth ground)
(mV input) (Iso. Gnd) (V
-)
(V+) (T+) (T
-)
3 K ȍ#ƒ&
&HQWHU
conductor
(clear)
Shield