Hach-Lange pHD sc User Manual

DOC023.52.03251.Jun05

pHD sc Digital Differential pH/ORP

Sensors

User Manual

DOC023.52.03251.Jun05

pHD sc Digital Differential pH/ORP

Sensors

User Manual

Table of Contents

Section 1 Specifications......................................................................................................................................... 1

Section 2 General Information ............................................................................................................................... 3

2.1 Safety Information ............................................................................................................................................... 3

2.1.1 Use of Hazard Information......................................................................................................................... 3

2.1.2 Precautionary Labels................................................................................................................................. 3

2.2 General Sensor Information ................................................................................................................................ 4

2.2.1 Sensor Body Styles ................................................................................................................................... 4

2.3 The Digital Gateway............................................................................................................................................ 6

2.4 Operating Precaution .......................................................................................................................................... 6

Section 3 Installation .............................................................................................................................................. 7

3.1 Connecting/Wiring the Sensor to the sc Controller ............................................................................................. 7

3.1.1 Attaching a sc Sensor with a Quick-connect Fitting .................................................................................. 7

3.2 Using the Digital Gateway................................................................................................................................... 8

3.2.1 Wiring the Digital Gateway ........................................................................................................................ 8

3.2.2 Mounting the Digital Gateway.................................................................................................................. 10

3.3 Installing the Sensor in the Sample Stream...................................................................................................... 11

Section 4 Operation .............................................................................................................................................. 13

4.1 Using an sc Controller....................................................................................................................................... 13

4.2 Sensor Setup .................................................................................................................................................... 13

4.3 Sensor Data Logging ........................................................................................................................................ 13

4.4 Sensor Diagnostics Menu for pH and ORP....................................................................................................... 13

4.5 pH Sensor Setup Menu..................................................................................................................................... 13

4.6 ORP Sensor Setup Menu.................................................................................................................................. 15

4.7 pH Calibration ................................................................................................................................................... 17

4.7.1 Two Point Automatic Calibration .............................................................................................................. 17

4.7.2 One Point Manual Calibration.................................................................................................................. 17

4.7.3 Two Point Manual Calibration .................................................................................................................. 18

4.8 ORP Calibration ................................................................................................................................................ 19

4.9 Concurrent Calibration of Two Sensors for pH and ORP .................................................................................. 19

4.10 Adjusting the Temperature .............................................................................................................................. 20

Section 5 Maintenance ......................................................................................................................................... 21

5.1 Maintenance Schedule ..................................................................................................................................... 21

5.2 Cleaning the Sensor ......................................................................................................................................... 21

5.2.1 Replacing the Standard Cell Solution and Salt Bridge ............................................................................ 22

Section 6 Troubleshooting ................................................................................................................................... 23

6.1 Error Codes....................................................................................................................................................... 23

6.2 Warnings........................................................................................................................................................... 23

6.3 Troubleshooting the pH Sensor......................................................................................................................... 24

6.3.1 Troubleshooting a pH Sensor without Integral Digital Electronics ........................................................... 24

6.3.2 Troubleshooting the pH Sensor with Integral Digital Electronics ............................................................. 25

6.4 Checking ORP Sensor Operation ..................................................................................................................... 26

6.4.1 Troubleshooting the ORP Sensor without Integral Digital Electronics ..................................................... 26

6.4.2 Troubleshooting the ORP Sensor with Integral Digital Electronics ..........................................................26

Section 7 Replacement Parts and Accessories ................................................................................................. 27

7.1 Replacement Items, Accessories, and Reagent and Standards....................................................................... 27

Table of Contents

Section 8 Warranty, liability and complaints....................................................................................................... 29

8.1 Compliance Information..................................................................................................................................... 30

Section 9 Contact .................................................................................................................................................31

Appendix A General pH Information....................................................................................................................32

A.1 pH Measurement Theory ............................................................................................................................32

A.2 PID Controller Basics .................................................................................................................................33

Appendix B Modbus Register Information..........................................................................................................35

Section 1 Specifications

Specifications are subject to change without notice.

Table 1 Differential pH and ORP Sensor Specifications

Specification Category pH Sensors

®3

PEEK

or Ryton®4 (PVDF)

Stainless Steel pH Sensor ORP Sensors

body, salt bridge of matching

®5

junction,

®6

Immersion mounting only, 316 SS Stainless Steel body

with Ryton

(PVDF) ends and

salt bridge.

PEEK® or Ryton® (PVDF) body, salt bridge of matching material with Kynar

glass and platinum (or glass and gold) process electrode, titanium ground electrode, and

O-ring seals

Viton

Wetted Materials

material with Kynar glass process electrode, titanium ground electrode, and Viton O-ring seals (pH sensor with optional HF-resistant glass process electrode has 316 stainless steel ground electrode, and perfluoroelastomer wetted O-rings; for other wetted O-ring materials consult the manufacturer)

Operating Temperature Range

Pressure/Temperature Limits (without mounting hardware)

–5 to 70 °C (23 to 158 °F) for sensor with integral digital electronics

–5 to 105 °C (23 to 221 °F) for analog sensor with digital gateway

6.9 bar at 105 °C (100 psi at 221 °F) for analog with gateway

6.9 bar at 70 °C (100 psi at 158 °F)

0 to 50 °C (32 to 122 °F) for sensor with integral digital electronics

N/A (immersion only)

–5 to 70 °C (23 to 158 °F) for sensor with integral digital electronics

–5 to 105 °C (23 to 221 °F) for analog sensor with digital gateway

6.9 bar at 70 °C (100 psi at 158 °F)

6.9 bar at 105 °C (100 psi at 221 °F) for analog with gateway

Maximum Flow Rate 3 m (10 ft) per second 3 m (10 ft) per second 3 m (10 ft) per second

junction,

Built-in Temperature Element

Stability

Maximum Transmission Distance

Sensor Cable (integral)

Components

Measuring Range

Probe Storage Temperature

NTC 300 ohm thermistor for automatic temperature compensation and analyzer temperature readout

0.03 pH per 24 hours, non-cumulative

1000 m (3280 ft) with termination box

NTC 300 ohm thermistor for automatic temperature compensation and analyzer temperature readout

0.03 pH per 24 hours, non-cumulative

1000 m (3280 ft) with termination box

Digital: PUR (polyurethane) 4-conductor with one shield, rated to 105 °C (221 °F), 10 m (33 ft) standard length

Analog: Five-conductor (plus two isolated shields) cable with XLPE (cross-linked

Digital: PUR (polyurethane) 4-conductor with one shield, rated to 105 °C (221 °F), 10 m (33 ft) standard length

polyethylene) jacket; rated to 150 °C (302 °F); 6 m (20 ft) standard length

Corrosion-resistant materials, fully-immersible probe with 10 m (30 ft) cable

–2.0 to 14.0 pH or –2.00 to 14.00 pH–2.0 to 14.0 pH or –2.00 to

14.00 pH

4 to 70 °C (40 to 158 °F); 0 to 95% relative humidity, non-condensing

NTC 300 ohm thermistor for analyzer temperature readout only — not for automatic temperature compensation

2 mV per 24 hours, non-cumulative

1000 m (3280 ft) with termination box

Digital: PUR (polyurethane) 4-conductor with one shield, rated to 105 °C (221 °F), 10 m (33 ft) standard length

Analog: Five-conductor (plus two isolated shields) cable with XLPE (cross-linked polyethylene) jacket; rated to 150 °C (302 °F); 6 m (20 ft) standard length

Corrosion-resistant materials, fully-immersible probe with 10 m (30 ft) cable

–1500 to +1500 mV

4 to 70 °C (40 to 158 °F); 0 to 95% relative humidity, non-condensing

Specifications

Table 1 Differential pH and ORP Sensor Specifications (continued)

Specification Category pH Sensors

Automatic from –10 to 105 °C (14.0 to 221 °F) with selection for NTC 300 ohm thermistor, Pt 1000 ohm RTD, or Pt 100 ohm RTD temperature element, or manually fixed at a user-entered

Temperature Compensation

temperature; additional selectable temperature correction factors (ammonia, morpholine, or user-defined pH/°C linear slope) available for pure water automatic compensation from 0.0 to 50 °C (32 to 122 °F)

Measurement Accuracy

±0.02 pH ±0.02 pH ±5 mV

Stainless Steel pH Sensor ORP Sensors

Automatic from –10 to 105 °C (14.0 to 221 °F) with selection for NTC 300 ohm thermistor, Pt 1000 ohm RTD, or Pt 100 ohm RTD temperature element, or manually fixed at a user-entered temperature; additional selectable temperature

N/A

correction factors (ammonia, morpholine, or user-defined pH/°C linear slope) available for pure water automatic compensation from 0.0 to 50 °C (32 to 122 °F)

Temperature Accuracy ±0.5 °C (0.9 °F) ±0.5 °C (0.9 °F) ±0.5 °C (0.9 °F)

Repeatability ±0.05 pH ±0.05 pH ±2mV

Sensitivity ±0.01 pH ±0.01 pH ±0.5 mV

Calibration Methods

Maximum Probe Immersion Depth/ Pressure

Two point automatic, one point automatic, two point manual, one point manual.

Submersible to 107 m (350 ft)/1050 kPa (150 psi)

Two point automatic, one point automatic, two point manual, one point manual.

Immersion only

one point manual

Submersible to 107 m (350 ft)/1050 kPa (150 psi)

Sensor Interface Modbus Modbus Modbus

Probe Cable Length

6 m (20 ft) + 7.7 m (25 ft) interconnect cable extension for analog sensor with digital gateway

10 m (31 ft) for sensor with integral digital electronics

6 m (20 ft) + 7.7 m (25 ft) interconnect cable extension for analog sensor with digital gateway

10 m (31 ft) for sensor with integral digital electronics

6 m (20 ft) + 7.7 m (25 ft) interconnect cable extension for analog sensor with digital gateway

10 m (31 ft) for sensor with integral digital electronics

Probe Weight 316 g (11 oz) 870 g (31 oz) 316 g (11 oz)

Probe Dimensions

Most pH applications are in the 2.5 to 12.5 pH range. The pHD™ Differential pH sensor with the wide-range glass process

See Figure 2 on page 5 through

Figure 3 on page 5.

See Figure 4 on page 5.

See Figure 2 on page 5 through Figure 3 on page 5.

electrode performs exceptionally well in this range. Some industrial applications require accurate measurement and control below 2 or above 12 pH. In these special cases, please contact the manufacturer for further details.

For best ORP measuring results in solutions containing zinc, cyanide, cadmium or nickel, the manufacturer recommends using

the pHD™ ORP sensor equipped with a gold electrode.

PEEK® is a registered trademark of ICI Americas, Inc.

Ryton® is a registered trademark of Phillips 66 Co.

Kynar® is a registered trademark of Pennwalt Corp.

Viton® is a registered trademark of E.I. DuPont de Nemours + Co.

Table 2 Digital Gateway Specifications

Weight 145 g (5 oz)

Dimensions 17.5 x 3.4 cm (7 x 1

/8 in.)

Operating Temperature –20 to 60 °C (–4 to 140°F)

Section 2 General Information

2.1 Safety Information

Please read this entire manual before unpacking, setting up, or operating this equipment. Pay attention to all danger and caution statements. Failure to do so could result in serious injury to the operator or damage to the equipment.

To ensure that the protection provided by this equipment is not impaired, do not use or install this equipment in any manner other than that specified in this manual.

2.1.1 Use of Hazard Information

DANGER Indicates a potentially or imminently hazardous situation which, if not avoided, could result in death or serious injury.

CAUTION Indicates a potentially hazardous situation that may result in minor or moderate injury.

Important Note: Information that requires special emphasis.

Note: Information that supplements points in the main text.

2.1.2 Precautionary Labels

Read all labels and tags attached to the instrument. Personal injury or damage to the instrument could occur if not observed

This symbol, if noted on the instrument, references the instruction manual for operation and/or safety information.

This symbol, when noted on a product enclosure or barrier, indicates that a risk of electrical shock and/or electrocution exists.

This symbol, if noted on the product, indicates the need for protective eye wear.

This symbol, when noted on the product, identifies the location of the connection for Protective Earth (ground).

This symbol, when noted on the product, identifies the location of a fuse or current limiting device. Electrical equipment marked with this symbol may not be disposed of in European public disposal

systems after 12 August of 2005. In conformity with European local and national regulations (EU Directive 2002/96/EC), European electrical equipment users must now return old or end-of life equipment to the Producer for disposal at no charge to the user.

Note: For all electrical products (marked or unmarked) which are supplied or produced by Hach-Lange, please contact the local Hach-Lange sales office for instructions for proper disposal.

General Information

2.2 General Sensor Information

Optional equipment, such as mounting hardware for the probe, is supplied with instructions for all user installation tasks. Several mounting options are available, allowing the probe to be adapted for use in many different applications.

The electronics of the sensor are encapsulated in a PEEK sensor has an integral NTC 300 ohm thermistor to automatically compensate pH readings for temperature changes. ORP sensors have a fixed temperature value of 25 °C/300 ohm (the ORP measurement is not temperature dependent).

2.2.1 Sensor Body Styles

pHD™ Differential pH and ORP sensors are available in three body styles:

• Convertible Body Style — has 1-inch NPT threads at both ends of the body for mounting in any of the following configurations:

• into a standard 1-inch NPT pipe tee

• into a pipe adapter for union mounting with a standard 1-½ inch pipe tee

• onto the end of a pipe for immersion into a vessel

Note: The convertible style sensor can also be retrofitted into existing installations for 1-½ inch LCP, Ryton, and epoxy sensors.

• Insertion Body Style — similar to the convertible sensor except that its 1-inch NPT threads are only on the cable end for mounting into a flow cell or the pipe adapter of a ball valve hardware assembly. This hardware enables the sensor to be inserted into or retracted from the process without stopping the process flow.

• Sanitary Body Style — features a built-in 2-inch flange for mounting into a 2-inch sanitary tee. Included with the sanitary-style sensor is a special cap and EDPM compound gasket for use with the sanitary hardware.

or Ryton® body. The pH

In addition, all probes are available with or without integral digital electronics. For applications with extreme temperatures, the sensor without integral digital electronics can be combined with the digital gateway.

Figure 1 Convertible Style Sensor Dimensions

1-inch NPT 1-inch NPT

59.44 mm (2.34 inches)

39.11 mm (1.54 inches)

232.15 mm (9.14 inches)

29.5 mm (1.16 inches)

271.3 mm (10.68 inches)

35.4 mm (1.36 inches)

26.7 mm (1.05 inches)

49.8 mm (1.96 inches)

Figure 2 Insertion Style Sensor Dimensions

General Information

35.4 mm (1.36 inches)

1-inch NPT

59.44 mm (2.34 inches)

39.11 mm (1.54 inches)

271.3 mm (10.68 inches)

Figure 3 Sanitary Style Sensor Dimensions

1-inch NPT

26.7 mm (1.05 inches)

29.5 mm (1.16 inches)

232.15 mm (9.14 inches)

54.6 mm (2.15 inches)

59.44 mm (2.34 inches)

39.11 mm (1.54 inches)

29.5 mm (1.16 inches)

49.8 mm (1.96 inches)

232.15 mm (9.14 inches)

271.3 mm (10.68 inches)

Figure 4 Stainless Steel Style Sensor (DPS1 and DRS5) Dimensions

43.9 mm (1.73 inches)

1-inch NPT

29.5 mm (1.16 inches)

4.5 mm (0.179 inches)

57.2 mm (2.25 inches)

34.8 mm (1.37 inches)

26.7 mm (1.05 inches)

54.6 mm (2.15 inches)

59.4 mm

(2.34 inches)

35.8 mm (1.41 inches)

264.67 mm (10.42 inches)

32.8 mm

(1.29 inches)

324.0 mm (12.755 inches)

General Information

2.3 The Digital Gateway

The digital gateway was developed to provide a means to use existing analog sensors with the new digital controllers. The gateway contains all the necessary software and hardware to interface with the controller and output a digital signal.

2.4 Operating Precaution

CAUTION If the pH process electrode breaks, handle the sensor very carefully to prevent injury.

Before placing the pH or ORP sensor into operation, remove the protective cap to expose the process electrode and salt bridge. Save the protective cap for future use.

For short-term storage (when sensor is out of the process for more than one hour) fill the protective cap with pH 4 buffer or DI water and place the cap back on the sensor. Keeping the process electrode and salt bridge moist will avoid slow response when the sensor is placed back in operation.

For extended storage, repeat the short-term storage procedure every 2 to 4 weeks, depending on the surrounding environmental conditions. See Specifications on page 1 for temperature storage limits.

The process electrode at the tip of the pH sensor has a glass bulb, which can be broken. Do not subject it to abrupt impact or other mechanical abuse.

The gold or platinum process electrode at the ORP sensor tip has a glass shank (hidden by the salt bridge) which can break. Do not subject this electrode to impact or other mechanical abuse.

Section 3 Installation

DANGER Only qualified personnel should conduct the tasks described in this section of the manual.

3.1 Connecting/Wiring the Sensor to the sc Controller

3.1.1 Attaching a sc Sensor with a Quick-connect Fitting

The sensor cable is supplied with a keyed quick-connect fitting for easy attachment to the controller (Figure 5). Retain the connector cap to seal the connector opening in case the sensor must be removed. Optional extension cables may be purchased to extend the sensor cable length. If the total cable length exceeds 100 m (300 ft), a termination box must be installed.

Note: Use of a load termination box other than Cat. No. 5867000 may result in a hazard.

Figure 5 Attaching the Sensor using the Quick-connect Fitting

Figure 6 Quick-connect Fitting pin assignment

Number Designation Wire Color

1+12 VDC Brown 2 Circuit Common Black 3 Data (+) Blue 4 Data (–) White 5 Shield Shield (grey wire in existing quick-disconnect fitting) 6Groove

Installation

3.2 Using the Digital Gateway

The digital gateway is designed to provide a digital interface to the controller.

3.2.1 Wiring the Digital Gateway

DANGER Explosion hazard. Do not connect or disconnect equipment unless power has been switched off or the area is known to be non-hazardous.

1. Route the cable from the sensor through the strain relief in the digital gateway then properly terminate the wire ends (see Figure 7).

Note: Do not tighten the strain relief until the digital gateway is wired and the two halves are threaded securely together.

2. Insert the wires as shown in Table 3 and Figure 8.

3. Make sure the O-ring is properly installed between the two halves of the digital

gateway and thread the two halves together. Hand tighten.

4. Tighten the strain relief to secure the sensor cable.

5. Connect the digital gateway to the controller.

Figure 7 Proper Wire Preparation and Insertion

1. Strip ¼-inch of insulation. 2. Seat insulation against connector with no bare wire exposed.

+ 30 hidden pages