Emerson Process Management TF396 instruction manual Section Description and Specifications

MODEL TF396	SECTION 1.0
	DESCRIPTIONS AND SPECIFICATIONS

SECTION 1.0

DESCRIPTION AND SPECIFICATIONS

1.1 FEATURES AND APPLICATIONS

The ion-selective field effect transistor (ISFET) pH elec- trode provides a stable pH measurement. Its rate of response can be ten times faster than glass electrodes, enabling better process control. Its short response time and increased stability at low temperatures make it suitable for use in cold processes like brine or water for cooling. Aging effects caused by temperature fluctuations or large changes of process pH are greatly reduced, providing longer intervals between calibration and maintenance of the sensor.

Because there is no glass bulb, it can be used in many applications that restrict or prohibit pH glass electrodes due to the risk of broken glass getting into the process. It may also provide longer sensor life in processes that will break or crack pH glass bulbs. By allowing direct installation into the process, costs for laboratory analysis of sample lines are greatly reduced.

The TUpH Reference technology includes a large area reference junction for minimum maintenance requirements. The reference junction provides an electrical connection between the reference electrode and the sample, and helps maintain a stable reference potential, regardless of the change in sample pH. The TUpH reference electrode junction (the entire plastic tip surrounding the ISFET electrode) maintains a steady reference signal, even in dirty applications, by resisting plugging (a common cause of pH signal drift). This large reference junction area (400 times

greater than typical teflon or ceramic junctions) is made of micron-sized reference pathways allowing for ionic exchange but preventing plugging by larger particles and will continue to send a steady pH signal, even in the dirtiest of applications. The field-proven TUpH reference junction tech- nology results in greatly reduced maintenance requirements.

The TUpH helical reference pathway resists reference poison- ing. Ions diffuse through the reference pathways and a charge is passed to the reference element. The reference element must be protected from contamination by poisoning ions such as sulfide, mercury, cyanide, and ammonia that will cause reference drift and offsets. The TUpH sensor's long internal reference pathway hinders the contaminants' migra- tion to the reference element thereby providing an increased sensor life.

All TUpH sensor models have been specifically designed for improved performance in harsh, dirty, or abrasive applica- tions where large quantities of suspended solids are present.

The Model TF396 offers a watertight sensor-to-cable connector that prevents cable twisting and eliminates the need for rewiring when replacing the sensor. The sensor cable includes an integral preamplifier cap with mating connector and is compatible with most Rosemount Analytical analyzers and transmitters.

1.2 SPECIFICATIONS Measurement Range: 2-12 pH Measuring element: ISFET Repeatability: ±0.05 pH

Response time to pH change: 99% in 30 seconds step change

Wetted Materials: Code -01:Polypropylene, EPDM, Ryton, Silicon.

Code -02:316SST, Titanium, Polypropylene, EPDM, Ryton, Silicon

Process Connections: Code -01:1 in. MNPT front and rear facing threads Code -02:2 in. Tri-Clamp connection

Temperature Range: 0 to 100°C (32 to 212°F) @ 50 psig

Pressure Range: -10 to 100 psig (32 to 790 kPa [abs]) at 50°C

Minimum Process Conductivity: 75 µS/cm; nominal: 100 µS/cm

Cable Lengths: 20 ft, 50 ft (6 m, 18 m)

Weight/Shipping Weight: 0.45 kg/0.9 kg (1 lb/2 lb)

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