High-Performance pH/ORP Sensor for Ultra-Pure Water Measurement

The ABB 700 ULTRA-D pH/ORP Digital Sensor is designed for applications where accurate pH measurement becomes challenging due to extremely low conductivity water conditions.

In ultra-pure water systems, traditional pH sensors may experience unstable readings because the low ionic concentration makes reference measurement more difficult. The 700 ULTRA-D addresses these challenges with a specialized reference system, high-performance glass electrodes, and advanced digital communication technology.

It is especially suitable for:

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  Boiler water monitoring
  
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  Demineralized water systems
  
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  Steam and water analysis systems
  
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  Reverse osmosis (RO) applications
  
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  Condensate and feedwater monitoring
  
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  Power generation processes
  

Designed for Ultra-Low Conductivity Applications

The biggest advantage of the 700 ULTRA-D is its ability to operate reliably in high-purity water applications where conventional pH sensors often struggle.

The sensor features a refillable KCl reservoir-fed reference system, which helps maintain stable reference potential and reduces measurement drift caused by electrolyte depletion.

It supports measurement applications down to approximately 0.055 μS/cm conductivity, making it suitable for demanding ultra-pure water processes.

Typical applications include:

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  Power plant boiler chemistry control
  
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  Semiconductor and electronics water systems
  
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  Pharmaceutical purified water
  
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  High-purity laboratory water systems
  

Triple Ceramic Junction for Stable Measurement

Reference junction performance directly affects pH sensor lifetime and measurement reliability.

The ABB 700 ULTRA-D uses a triple ceramic junction design to improve:

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  Response speed
  
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  Measurement stability
  
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  Resistance to junction blockage
  
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  Long-term sensor performance
  

This design helps maintain reliable readings in applications where measurement accuracy and uptime are critical.

Digital EZLink™ Connection for Simplified Integration

Unlike traditional analog sensors requiring manual configuration and complex commissioning, the 700 ULTRA-D uses ABB’s EZLink™ digital connection technology.

Benefits include:

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  Automatic sensor recognition
  
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  Faster commissioning
  
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  Reduced installation errors
  
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  Digital communication with compatible ABB analyzers
  

The plug-and-measure design helps simplify sensor replacement and maintenance procedures.

Advanced Sensor Diagnostics and Predictive Maintenance

Unexpected sensor failure can lead to inaccurate water chemistry control and unnecessary downtime.

The 700 ULTRA-D includes advanced diagnostic functions that help users:

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  Monitor sensor condition
  
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  Identify potential failures
  
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  Detect end-of-life conditions
  
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  Improve maintenance planning
  

This allows maintenance teams to replace sensors based on actual condition rather than fixed schedules.

High Accuracy pH and ORP Measurement Capability

The 700 ULTRA-D supports both pH and ORP measurement depending on electrode configuration.

Measurement capability includes:

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  pH range: 0 to 14 pH
  
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  ORP range: -2000 to +2000 mV
  
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  Temperature measurement via integrated sensor
  

Available measuring electrodes include:

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  High-performance pH glass
  
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  Low-temperature pH glass
  
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  Platinum ORP electrode
  

Reliable Reference System for Long-Term Operation

The sensor uses a flowing KCl electrolyte reference system with:

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  Ag/AgCl double junction
  
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  Ceramic reference junction
  
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  Rechargeable electrolyte reservoir
  

This design provides improved stability compared with standard reference systems, especially in ultra-pure water environments where reference contamination and drift can become major challenges.

Designed for Power and High-Purity Industries

The ABB 700 ULTRA-D is mainly selected for industries where water quality directly affects equipment reliability and process efficiency.

Typical industries include:

Power Generation

Used for:

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  Boiler water monitoring
  
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  Steam cycle chemistry control
  
• 
  Condensate quality measurement
  

Pharmaceutical Industry

Suitable for:

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  Purified water systems
  
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  High-purity process water
  
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  Quality monitoring applications
  

Semiconductor & Electronics

Used for:

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  Ultra-pure water production
  
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  Contamination-sensitive processes
  

FAQ

What is ABB 700 ULTRA-D used for?

The ABB 700 ULTRA-D is a digital pH/ORP sensor designed mainly for ultra-pure water applications requiring high measurement stability and accuracy.

What makes 700 ULTRA-D different from standard pH sensors?

The main difference is its specialized design for ultra-low conductivity water. It uses a refillable KCl reservoir, triple ceramic junction, and digital diagnostics to improve stability in difficult high-purity applications.

Can ABB 700 ULTRA-D measure ORP?

Yes. The sensor supports ORP measurement using a platinum electrode configuration, with a measurement range up to ±2000 mV.

What is the difference between ABB 700 ULTRA-D and 700 ULTRA?

The main difference is the communication method:

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  700 ULTRA-D: Digital version with ABB EZLink™ connection and advanced diagnostics.
  
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  700 ULTRA: Analog version for traditional analyzer connections.
  

Is ABB 700 ULTRA-D suitable for wastewater applications?

Generally, no. The 700 ULTRA-D is optimized for high-purity and ultra-pure water applications, not heavily contaminated wastewater.

For wastewater and harsh industrial processes, ABB 100 or 500 series pH/ORP sensors are usually more suitable.

What is the maximum operating temperature of ABB 700 ULTRA-D?

The sensor supports process temperatures up to 100 °C (212 °F) depending on configuration.