Georg Fischer 8750 Operating Manual

Signet 8750-2 pH/ORP Transmitter

*3-8759.090-2*

3-8750.090-2 Rev. G 3/06 English

English

CAUTION!

• Remove power to unit before wiring input and output connections.

• Follow instructions carefully to avoid personal injury.

Contents

1.Installation

2.Speciﬁ cations

3.Electrical Connections

4.Menu Functions

Signet pH/ORP

Transmitter

Relay 1

1. Installation

ProcessPro transmitters are available in two styles: panel mount and ﬁ eld mount. The panel mount is supplied with the necessary hardware to install the transmitter. This manual includes complete panel mounting instructions. Field mounting requires a separate mounting kit. The 3-8050 Universal kit enables the transmitter to be installed virtually anywhere. Detailed instructions for ﬁ eld installation options are included with the 3-8050 Universal kit.

1.1 Panel Installation

1. The panel mount transmitter is designed for installation using a 1/4 DIN Punch. For manual panel cutout, an adhesive template is provided as an installation guide. Recommended clearance on all sides between instruments is 1 inch.

2. Place gasket on instrument, and install in panel.

3. Slide mounting bracket over back of instrument until quick-clips snap into latches on side of instrument.

4. To remove, secure instrument temporarily with tape from front or grip from rear of instrument. DO NOT RELEASE.

Press quick-clips outward and remove.

panel

terminals

d n

sr G

)

D L

r IN s

) D

t -

tem

ste y S

+ p

o o L

r V

s n e

)

A L

t +

u tp u

quick-clips

96 mm

(3.8 in.)

FRONT VIEW

Field Mount &

Panel Mount

96 mm (3.8 in.)

42 mm (1.7 in.)

106 mm (4.2 in.)

SIDE VIEW

Field Mount

8050

64 mm (2.5 in.)

82 mm (3.23 in.)

41 mm (1.6 in.

)

SIDE VIEW

Panel Mount

Optional Rear Cover

56 mm (2.2 in.)

97 mm

(3.8 in.)

92 mm (3.6 in.)

gasket

latch

Panel Mount Installation Detail

10.20 pH

25.0 C

mounting

Relay 2

ENTER

bracket

2. Speciﬁ cations

General

Compatible electrodes: Signet 2714-2717 Electrodes with 2720 pH/ORP Preampliﬁ er, 2764-2767 and 2774-2777 Electrodes with 2760-1,-2 pH/ORP Preampliﬁ er Accuracy: ±0.03 pH, ± 2 mV's ORP Enclosure:

• Rating: NEMA 4X/IP65 front

• Case: PBT

• Panel case gasket: Neoprene

• Window: Polyurethane coated polycarbonate

• Keypad: Sealed 4-key silicone rubber

• Weight: Approx. 325g (12 oz.) Display:

• Alphanumeric 2 x 16 LCD

• Contrast: User selected, 5 levels

• Update rate: 1 second

Electrical

Power: 12 to 24 VDC ±10%, regulated, 220 mA max. Sensor input range:

• pH: 0.00 to 14.00 pH

• Temp. (pH only) 3K Balco, -25 to 120°C (-13 to 248°F)

• ORP: -1000 to +2000 mV, isolated (10KΩ I.D. resistance T+, T-)

Current output:

• 4 to 20 mA, isolated, fully adjustable and reversible

• Max loop impedance: 50 Ω max. @ 12 V 325 Ω max. @ 18 V 600 Ω max. @ 24 V

• Update rate: 0.5 seconds

• Accuracy: ±0.03 mA @ 25°C, 24 V Relay outputs (2 sets mechanical SPDT contacts):

• Maximum voltage rating: 5 A @ 30 VDC, or 5 A @ 250 VAC resistive load

• Hi or Lo programmable with adjustable hysteresis

• Pulse programmable (maximum 400 pulses/minute)

Environmental

• Operating temperature: -10 to 70°C (14 to 158°F)

• Storage temperature: -15 to 80°C (5 to 176°F)

• Relative humidity: 0 to 95%, non-condensing

• Maximum altitude: 2000 m (6562 ft)

• Insulation category: II

• Pollution degree: 2

Standards and Approvals

• CE, UL listed

• Immunity: EN50082-2

• Emissions: EN55011 Class B

• Manufactured under ISO 9001 and ISO 14001

3. Electrical Connections

Caution: Failure to fully open terminal jaws before removing wire may permanently damage instrument.

Wiring Procedure

1. Remove 0.5 - 0.625 in. (13-16 mm) of insulation from wire end.

2. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.

3. Insert exposed (non-insulated) wire end in terminal hole until it bottoms out.

4. Release orange terminal lever to secure wire in place. Gently pull on each wire to ensure a good connection.

Wiring Removal Procedure

1. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.

2. When fully open, remove wire from terminal.

Wiring Tips:

• Do not route sensor cable in conduit containing AC power wiring. Electrical noise may interfere with sensor signal.

• Routing sensor cable in grounded metal conduit will help prevent electrical noise and mechanical damage.

• Seal cable entry points to prevent moisture damage.

• Only one wire should be inserted into a terminal. Splice double wires outside the terminal.

Terminals 5-10: Relay Outputs

Two sets mechanical SPDT contacts, programmable (see CALIBRATE menu) as:

• High or Low with adjustable hysteresis

• proportional pulse based on pH or ORP

• May be disabled (Off) if not used.

Terminals 15-18: Sensor connections

15-16 are mV (pH or ORP) input from the electrode. 17-18 are temperature input from the pH electrode or 10KΩ identifying resistor from the ORP electrode.

Terminals 3 and 4: Loop Power

12-24 VDC ±10% system power

and current loop output.

Max. loop impedance:

50 Ω max. @ 12 V 325 Ω max. @ 18 V 600 Ω max. @ 24 V

Terminals 1 and 2: AUXILIARY power

Provides power for relay operation.

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Tem p -

(WHITE)

Tem p +

(GREEN)

Iso. GND (BLUE)

Relay 2

(NO)

Relay 2

(COM)

Relay 2

(NC)

Relay 1

(NO)

Relay 1

(COM)

Relay 1

(NC)

Terminals 11-14: Preampliﬁ er power and grounds

11-12 are DC voltages from the 8750 to power the

preampliﬁ er.

13-14 are ground terminals for the sensor and for

earth ground

mV Input (BROWN)

Earth GND

Sensr Gnd (SHIELD)

V(BLACK)

V+ (RED)

8750-2 pH/ORP Transmitter

3.1 Sensor Input Connections

Terminals

* (connection of terminal 14 to Earth GND

White (Temp)

Green (Temp)

Blue (ISO GND)

Brown (mV input)

15 14

Silver (Shield)

Black (V-)

Red (V+)

may reduce electrical interference)

3.2 System Power/Loop Connections

Stand-alone application, no current loop used

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Preamp: Signet 2720

Twist-Lock Electrodes

Transmitter

Terminals

4 3

3 2

2 1

Preamp: Signet 2760-1 Signet 2760-2

DryLoc Electrodes

Transmitter

10.20 pH

Signet pH/ORP

Transmitter

Relay 1

Power

Supply

12-24 VDC

25.0 C

Relay 2

ENTER

≤ 400 ft. (122 m)

Connection to a PLC/Recorder, separate supply

Connection to a PLC with built-in power supply

PLC or Recorder

Transmitter

Terminals

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Transmitter

Terminals

12-24 VDC

Loop Input

4-20 mA

Power

Supply

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

AUX power required for all 8750-2 systems

Example: Two transmitters connected to PLC/Recorder with separate power supply

PLC or Recorder

Channel 1 4-20 mA in

Channel 2 4-20 mA in

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Transmitter 1

Terminals

Transmitter 2

Terminals

Internal

PLC

Connection

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

PLC Terminals

Loop Input

4-20 mA

Power

Supply

12-24 VDC

Power

Supply

38750-2 pH/ORP Transmitter

3.3 Relay Output

The relay outputs can be programmed to respond when the pH/ ORP value moves above or below a setpoint, or it can be used to generate a pulse that is proportional to the pH/ORP value. The relays can be disabled if not in use.

• Low Relay triggers when the pH/ORP is less than the setpoint. The relay will relax when the pH/ORP moves above the setpoint plus the hysteresis value.

• High Relay triggers when the pH/ORPis greater than the setpoint. The relay will relax when the pH/ORP drops below the setpoint plus the hysteresis value.

Process

• Proportional Pulsing The relay output will generate a 100 mS pulse at the rate deﬁ ned by settings in the CALIBRATE menu (see page 6)

In the example below:

• The output will be 0 pulses/min. at pH values less than 5.0.

• The output will be 50 pulses/min. at 7.5 pH.

• The output will be 100 pulses/min. at pH values above 10 pH.

100 pulses

Hysteresis

Low Setpoint

Relay Output Rate:

0 to 100 Pulses/min.

0 pulses

Relay energized

Time

Starting point

endpoint

Relay relaxed

Process

High Setpoint

Hysteresis

Time

VIEW menu

• During normal operation, ProcessPro displays the VIEW menu.

• When using the CALIBRATE or OPTIONS menus, ProcessPro will return to the VIEW menu if no activity occurs for 10 minutes.

• To select the item you want displayed, press the UP or DOWN arrow keys. The items will scroll in a continuous loop. Changing the display selection does not interrupt system operations.

• No key code is necessary to change display selection.

• Output settings cannot be edited from the VIEW menu.

Pulse rate

10.20 pH

25.0 C

Signet pH/ORP

Transmitter

Relay 1

Relay 2

ENTER

View Menu for pH

Display Description

7.00 pH

12.6 ºC

All of the VIEW displays below are temporary. The permanent display will return after ten minutes.

Input: 307 mV

Loop Output:

14.16 mA

Last CAL: 03-17-66 >

EASY CAL: >

Monitor the pH and the Temperature input from the sensor. This is the Permanent display.

Monitor the millivolt input from the electrode. Use this display to determine the relative condition of your electrode during periodic calibration. (7 pH buffer = 0 mV, ±50 mV)

Monitor the 4-20 mA Loop output.

Monitor date for scheduled maintenance or date of last calibration.

Easy Cal is the fastest and simplest periodic calibration method. Requires 4 pH, 7 pH and 10 pH. (Any two)

8750-2 pH/ORP Transmitter

+ 8 hidden pages

Georg Fischer 8750 Operating Manual

Specifications and Main Features

Frequently Asked Questions

User Manual