GF 2751-7 User manual

GF 2751-7 pH Electronics
English
The 2751-7 pH Smart Sensor Electronics processes analog signals from a pH electrode
and transmits digital data via a three wire cable to the 9950-X Chlorine Controller.
The DryLoc®electrode connector quickly forms a robust assembly with the sensor.
Smart Sensor Electronics o󰀨ers broken glass and high impedance detection, manufacturing
electrode data and storage of environmental extremes for temperature and pH levels.
The pH electrode is necessary to accurately calculate Free Chlorine levels in applications
that are above pH 7.1 to a maximum pH level of 8.2. Because Chlorine Dioxide is not
pH dependent, the pH electronics and electrode are o󰀨ered as an option.
The data stream also includes important information regarding the performance and life
span of the pH electrode. The 9950-X provides the operator with a calculated slope of the
electrode (electrode health) and can detect when the electrode requires cleaning.
The 2751-7 is compatible with 4630-13, 4630-14, 4630-23,4630-24, 4630-33, 4630-34, and
4632-13 only. For all other 4630-XX part numbers please contact the factory for support.
* NOTE: The 9950-X Chlorine Controller is not compatible with the standard 9950 controller.
Operating Instructions
Description
• English
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• 中文
*3-9900-1P-1.090*
3-2751-7.090 Rev 1 02/22
WARNING
Refer to the 3-463X Chlorine manual for
additional important information regarding
safety and installation.

2GF 2751-7 pH Electronics
Caution / Warning / Danger
Indicates a potential hazard. Failure to follow all warnings
may lead to equipment damage, injury, or death
Electrocution Danger
Alerts user to risk of potential of injury or death via
electrocution.
Electrostatic Discharge (ESD)
Alerts user to risk of potential damage to product by ESD
Personal Protective Equipment (PPE)
Always utilize the most appropriate PPE during
installation and service of GF products.
Note / Technical Notes
Highlights additional information or detailed procedure.
Refer to your local Georg Fischer Sales o󰀩ce for the most
current warranty statement.
All warranty and non-warranty repairs being returned must
include a fully completed Service Form and goods must be
returned to your local GF Sales o󰀩ce or distributor.
Product returned without a Service Form may not be
warranty replaced or repaired.
GF products with limited shelf-life (e.g. pH, ORP, chlorine
electrodes, calibration solutions; e.g. pH bu󰀨ers, or other
solutions) are warranted out of box but not warranted against
any damage, due to process or application failures (e.g. high
temperature, chemical poisoning, dry-out) or mishandling (e.g.
broken glass, damaged membrane, freezing and/or extreme
temperatures).
• Remove electrical power from the transmitter before wiring
input connections.
• Follow instructions carefully to avoid personal injury or
damage to the electronics.
Warranty Information
Safety Information
Dimensions
Specications
61.0 mm
(2.40 in.)
94 mm
(3.69 in.)
General
Compatible Electrode ..........2724-00 Flat pH Electrode
Compatible Instrument ........9950-X Chlorine Controller
Mounting ..............................DryLoc
®
connection
Materials ..............................PC+PBT
Cable ...................................4.6 m (15 ft) 3 conductor shielded,
22 AWG
Shipping Weight ..................0.64 kg (1.41 lb)
Performance
Electronics Accuracy ...........± 0.02 pH @ 25 °C
pH........................................ ≤ 0.01 pH
Response Time....................< 6 s for 95% of change
(includes electrode response)
Operational Range ..............-1.0 to 15.00 pH
Electrical
Input Specications
Input Impedance ..................> 10
11
Ω
Temperature Drift .................± 0.002 pH per ºC
Input Resolution...................0.02 pH, 0.3 ºC
Output Specications
Digital (S³L)..........................Serial ASCII, TTL level 9600 bps
Max. Cable Length ..............30 m (100 ft)
Environmental
Storage Temperature ...........–20 °C to 85 °C (–4 °F to 185 °F)
Operating Temperature ........0 °C to 85 °C (32 °F to 185 °F)
(electronics only)
Relative Humidity................. 0 to 95%, non-condensing
Enclosure Requirements .......NEMA 4X/IP65 with electrode
connected
Standards and Approvals
• CE, WEEE
• RoHS Compliant
• Manufactured under ISO 9001, ISO 14001 and ISO 45001
China RoHS (Go to gfsignet.com for details)
Declaration of Conformity according to FCC Part 15
This device complies with Part 15 of the FCC rules.
Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received,
including interference that may cause undesired operation.

3
GF 2751-7 pH Electronics
Lubricate O-rings with a non-petroleum based, viscous lubricant (grease) compatible with the system.
It is not necessary to lubricate the electrodes body O-ring when using the 463X Flow Cell.
Do Not Use Lubricant or Sealing Tape on Threads.
Do Not Overtighten.
3610 Flow Tee Installation
1. Lubricate the Dry-Loc and the electrode body O-rings
with a non-petroleum lubricant.
2. Insert fully into the tting.
3. Install bottom retaining nut onto the tting and hand
tighten. Do not use tools.
1. Lubricate the Dry-Loc O-ring with a non-petroleum
lubricant. (DO NOT lubricant the electrode body O-ring.)
2. Insert the sensor into the 2751-7.
3. Insert into the Chlorine (CI) ow chamber and push
lightly to secure.
pipe tee
pipe tee
pipe tee
9950-X
CH 2
Installation
The bottom yellow nut is
not used when using the 2751-7
pH electronics with the 463X Flow
Cell.
3-2724-00
Flat pH Electrode
463X Flow Cell
463X Flow Cell Installation
CHEMICAL COMPATIBILITY WARNING
The retaining nuts of pH and ORP sensors are not designed for prolonged contact with aggressive substances.
Strong acids, caustic substances and solvents or their vapor may lead to failure of the retaining nut, ejection of
the sensor and loss of the process uid with possibly serious consequences, such as damage to equipment and
serious personal injury. Retaining nuts that may have been in contact with such substances, e.g. due to leakage
or spilling, must be replaced.
Wiring
Wiring to the 9950-X Chlorine Controller
To replace the 2751-7 pH electronics in a 463X Chlorine panel:
• Measuring from the yellow housing threaded end, cut the cable to approximately 838 mm (33 in.).
• Remove approximately 10 mm (0.4 in.) of insulation and tin each conductor before inserting into terminals.
• For calibration and conguration please refer to the 463X Chlorine Analyzer System and
9950-X Chlorine Controller manuals.
CH1
+V
FREQ
DATA
GND
Black
White
X
No connection
Shield
Red
IN
OUT
pH Cl

Georg Fischer Signet LLC, 5462 N. Irwindale Avenue, Irwindale, CA 91706 U.S.A. • Tel. [phone] • Fax [phone]
For Worldwide Sales and Service, visit our website: www.gfps.com • or call (in the U.S.): [phone]
For the most up-to-date information, please refer to our website at www.gfps.com
3-2751-7.090 Rev 1 02/22 English © Georg Fischer Signet LLC 2022
Ordering Information
Mfr. Part No. Code Description
3-2751-7 159 001 957 pH Electronics (4630-13, 4630-14, 4630-23, 4630-24, 4630-33, 4630-34 and 4632-13)
3-2750-7 159 001 671 pH Electronics (Retired 4630/32-10,11,20,21,30,31)
3-2724-00 159 001 545 Flat pH Electrode Dryloc®, Pt1000, 3/4" NPT or Signet tting
3-2724-01 159 001 548 Flat pH Electrode, DryLoc®, Pt1000, ISO 7/1-R¾ or Signet ttings
3-0700.390 198 864 403 pH Bu󰀨er kit
3-2700.395 159 001 605 Calibration kit: included 3 PP cups, cup stand, 1 pint pH 4.01, 1 pint pH 7.00
3822-7004 159 001 581 pH 4.01 bu󰀨er solution, 1 pint (473 ml) bottle
3822-7007 159 001 582 pH 7.00 bu󰀨er solution, 1 pint (473 ml) bottle
3800-5000 159 838 107 3.0M KCl Storage solution for pH and ORP, 1 pint (473 ml) bottle
3-2700.398 159 001 886 O-ring lubricant kit (5 packs of Super Lube, 1cc each)