LaMotte pHPLUS DIRECT Instruction Manual

Instruction Manual

pHPLUS DIRECT

pH/mV/ISE Meter

Code 5-1936

PREFACE

This instruction manual serves to explain the use of the pHPLUS DIRECT
meter.

It functions in two ways: first as a step by step guide to help you operate the
meter; second, it serves as a handy reference guide.

This manual is written to cover as many anticipated applications of the
pHPLUS DIRECT meter as possible. If there are doubts in the use of this
meter, please do not hesitate to contact the LaMotte Tech Service
Department.

LaMotte will not accept any responsibility for damage or malfunction to the
meter caused by improper use of the instrument.

The information presented in this manual is subject to change without notice
as improvements are made, and does not represent a commitment on the part
of LaMotte Company.

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Table of Contents

1. Introduction ............................. 5

2. Getting Started ........................... 6

2.1 Description of Keypad Functions ................... 6

2.2 Description of LCD Annunciations ................. 7

2.3 Inserting & Removing the Rubber Boot ............... 7

2.4 Inserting New Batteries ........................ 8

2.5 Battery Replacement ......................... 8

2.6 Connecting the Electrode and Temperature Sensor .........8

2.7 Condition the pH Electrode ..................... 9

2.8 Switching the Meter On ....................... 9

3. Calibration ............................. 10

3.1 pH Calibration............................ 10

3.2 Selection of pH buffer standards .................. 11

3.2.1 Resetting the User Calibrated Values ............... 11

3.2.2 pH Calibration using USA standard buffers ...........12

3.2.3 pH Calibration using NIST standaard buffers ...........13

3.2.4 pH Calibration using Pb Standard buffers ............14

3.3 Ion Calibration ........................... 15

3.3.1 Multi-point Ion Calibration ................... 16

3.4 Temperature Calibration ...................... 17

3.4.1 With Temperature probe .................... 17

3.4.2 Without Temperature probe (no ATC) .............18

4. Measurement ............................ 19

4.1 Taking Measurements ........................ 19

4.2 Millivolt (mV) Reference Check .................. 19

4.3 Holding a Reading .......................... 19

4.4 Releasing a Held Reading ...................... 19

5. Electrode Care and Maintenance .................20

6. Troubleshooting .......................... 20

7. Specifications ...........................21

8. Accessories ............................. 22

9. Warranty Information ..................... 22-23

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1. INTRODUCTION

Thank you for purchasing the pHPLUS DIRECT meter. This
microprocessor-based handheld meter is economical and easy to use. It has a
large custom LCD (Liquid Crystal Display) for clear and easy reading.

The pHPLUS DIRECT measures pH, mV (ORP), temperature and ion
concentration of various ions (mono and di valence) with ion selective
electrodes (ISEs).

Included with your meter are a robust rubber boot, 4 alkaline “AAA” batteries,
buffer solutions, accessories, temperature sensor, instruction manual and a
warranty card. To order other accessories and buffer calibration or standard
solutions, please refer to Section 8 on Accessories for more information.

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2. GETTING STARTED

2.1 Description of Keypad Functions

The pHPLUS DIRECT has six keys on its splash-proof keypad with tactile
feedback. The keys include ON/OFF, HOLD/ENTER, CAL, MODE, p
and q keys.

Powers meter on and off. Meter starts up in the mode that you were in
before turning the meter off.

Selects measurement mode for Ion, mV, pH and Temperature.

Allows calibration for Ion, pH, mV or Temperature, or to abort
calibration without confirming any set value.

Allows you to increase values during calibration mode.

Allows you to decrease values during calibration mode.

Freezes the measured reading for easy viewing.

Confirms calibration value.

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CAL

MODE

ON

OFF

HOLD

ENTER

ON

OFF

CAL

HOLD

ENTER

HOLD

ENTER

MODE

2.2 Description of LCD Annunciators

The meter has a large custom LCD that consists of 3½-digit segments and
operation annunciators for pH, mV or °C (Temperature). Note that there is no
annunciator shown in the Ion mode. Other annunciators include “HO” (when
the HOLD function is activated) and “LO” (low battery condition).

2.3 Inserting & Removing the Rubber Boot

1. To remove the meter from the rubber boot, push out the bottom edges of

the meter until it is completely out of the boot. Ensure that the cables of
the ISE/pH electrode or temperature probe are not connected

2. To insert the meter into the rubber boot, slide the top of the meter into the

boot before pushing the bottom edge of the meter down to set it into
position. Lift up the stand on the back of the meter for bench top
applications if desired.

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2.4 Inserting New Batteries

The battery compartment is found at the back of the instrument. To open the
battery compartment, push in the direction of the arrow and lift up the cover.
Note the polarity of the batteries before inserting them into position. After
replacement, replace the cover and press down until it locks tight.

2.5 Battery Replacement

A“LO” annunciator in the LCD alerts you when battery power is running low.
Replace the batteries with the type recommended by the manufacturer.

Caution: Power off the meter when changing the batteries.

2.6 Connecting the Electrode and Temperature Sensor

To connect the electrode to the meter, align the connector slots with the posts
of the meter socket and rotate the connector clockwise until it locks. Do not
force it when connecting. To remove the electrode, simply rotate the
connector in a counterclockwise direction until it unlocks, and slide the
connector off the socket.

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