Images are representations only.
SM21 Electrode for pH/Redox
Brand: Yokogawa Electric CorporationThe glass membrane is the most important part of the complete pH measuring loop.
pH sensitive glass has the particular property that alkali metal ions present in the texture of the glass are exchanged with H+ ions of the liquid.
The selection of the correct type of glass electrode depends on both the type of glass membrane thickness of the glass membrane.
In SM21 "Single glass electrodes" there are two types of glass are available, as described here:
- "G" glass: This is used for the membranes of electrodes in processes where the nominal pH value varies between pH0 and pH10. Since this type of glass has a wide application range it is also termed “general-purpose” glass.
- "L" glass: The application of “L” glass is for measurements in alkaline media with high process temperatures.
- Low resistance glass for fast response and sensitivity
- High resistance glass for chemical resistance
- L-glass sensors for high temperature chemically harsh applications
- G-glass sensors for all general applications
- "All glass" construction
- Dimensions and design meet the requirements of DIN 19263
- Isothermal point of intersection: pH 7 (nominal value at 0 mV)
- Maximum pressure: 1,000 kPa (10 bar)
- Metal foil screening
- Bulb membrane for general-purpose
- Dome shaped membrane for “Heavy Duty” applications
Connector Type
Reference System
Kind of Membrane
Membrane Shape
View Details
Part Number / SKU
SM21D-AG2
Specifications
Applications
- Harsh Applications
- High Temperature Applications
- Light, Laboratory
Approvals & Certifications
- IEC
BSP Connection
- G 1/4" Male
Electrical Connectors
- DIN 19263
- PG 13.5
Environmental Protection
- IP65
- Watertight
Maximum System Pressure
- psi: 145 (kPa: 1,000, bar: 10) - Glass Sensors
NACE & NIST
- NIST
Resistance
- Glass Resistance: 25 to 900 MΩ
Sensor, Probe Diameter
- 0.47" (12 mm)
Sensor, Probe Length
- 4.72" (120 mm)
Sensor, Probe Material
- Ceramic
- pNa Glass
- PTFE
- Zirconium
Sensor, Probe Type
- Bulb
Temperature Range
- 0° to 130° C (32° to 266° F) - Glass Sensors
