3
Signet 3719 pH/ORP Wet-Tap
Notes on Location, Orientation and Required Clearance
•
The 3719-1 is designed for use in pipes up to 4 in.
•
The 3719-2 is designed for use in pipes from 6 to 12 in.
•
Select a location that will provide suf
fi
cient clearance to
remove and insert the electrode.
•
The 3719 can be mounted in any orientation, including
horizontal and inverted. Avoid the 12 o'clock position. In the
presence of sediment, avoid the 6 o'clock position.
•
If inverted, use caution when removing the sensor.
Residual
fl
uid may be
present in the retraction
housing. Keep electrode
connector clean and dry at
all times.
Any angle OK
a
b
c
d
e
d
a) 3719 pH/ORP Wet-Tap
b) Customer-supplied
Low-Pro
fi
le Clamp-on Saddle Fitting
(ASTM sizes 2½ to 12 in.)
c) DryLoc
®
pH or ORP Electrode (6 versions available; see
ordering infomation on page 8.)
(DryLoc
®
refers to the electrode connector style)
d) 2750 or 2760 DryLoc
®
pH/ORP Preampli
fi
er/Sensor
electronics
e) Output signal options:
2750:
- Digital (S
3
L)
- 4 to 20 mA
2760:
- Analog mV Output- Digital (S
3
L)
All components (items a–d) are sold separately.
General
Compatible sensors:
2756-WT
DryLoc
®
pH Electrode
2756-WT-1 DryLoc pH Electrode
2756 -WTP DryLoc plastic pH electrode
2756-WTP-1 DryLoc plastic pH electrode
2757-WT DryLoc ORP Electrode
2757-WTP DryLoc plastic ORP electrode
Shipping Weight
Wet-tap assembly ............. 1.2 kg (2.7 lbs.)
Electrode ........................... 0.13 kg (0.3 lb)
Process Connection ............. 3-3719-11: 1½ in. NPT
3-3719-21: 2 in. NPT
3-3719-12: ISO 7/1-R1½
3-3719-22: ISO 7/1-R2
Wetted materials
Retraction Housing ............... CPVC
O-rings .................................. FKM
Electrode Body ..................... Glass or Plastic
Electrode junctions ............... Porous PTFE
Electrode sensing surface .... Glass Membrane (pH)
Platinum (ORP)
Electrode O-rings.................. FKM
Other Materials
Locking Shroud..................... PVC
Hardware .............................. 316 stainless steel
Performance
Maximum Flow Velocity ........ 3 m/s (10 ft/s)
Response Time
pH ..................................... <5s for 95% of signal change
ORP
.................................. Application
dependent
Drift ....................................... < 2 mV per week
Operating Range
pH ..................................... 0 to 14 pH
ORP .................................. –2000 to +2000 mV
Reference Junctions ............. Porous PTFE
Electrolyte ............................. 3.5M KCl
Elements............................... Ag/AgCl
Temp. Sensor (pH) ............... 3K Balco (3-2756-WT-1, WTP-1)
PT1000 (3-2756-WT, -WTP)
Temp. response time (
τ
) ....... 438 s
Sodium Ion Error .................. < 0.05 pH in 0.1 molar
Na+ ion at 12.8 pH
Impedance (pH) .................... <150 M
Ω
@ 25 °C
Storage Temperature
Wet-tap assembly ............. -15 to 120 °C (5 to 248 °F)
Electrode ........................... 0 to 50 °C (32 to 122 °F)
Standards and Approvals
Manufactured under ISO 9001 and 14001
China RoHS (Go to www.gfsignet.com for details)
25
Specifi cations
System Overview
Installation
