HF scientific MicroTOL Online Turbidimeter User Manual

OWNERS MANUAL

Micro TOL

0-1000 NTU

HF scientific, inc.
3170 Metro Parkway
Ft. Myers, FL 33916
Phone: [phone]
Fax: [phone]
E-Mail: [e-mail]
Website: www.hfscientific.com

Catalog No. 24031 (12/04)
Rev. 2.7

DECLARATION OF CONFORMITY

Application of Council Directive

Standard to Which Conformity is Declared:

Product Safety - Tested and passed CE EN61010-1: 1990 + A1: 1992 (73/32 EEC)

- Tested and passed ETL (tested to UL3111-1)

- Tested and passed ETLc (tested to CSA C22.2#1010-2-010)

Immunity – Tested and passed EN61326: 1998
Including:
EN61000-4-2
EN61000-4-3
EN61000-4-4
EN61000-4-5
EN61000-4-6
EN61000-4-8
EN61000-4-11

Emissions - Tested and passed EN61326 (EN55011 Class B)

Manufacturer’s Name: HF scientific, inc.

Manufacturer’s Address: 3170 Metro Parkway, Fort Myers, Florida 33916-7597

Importer’s Name:

Importer’s Address:

Type of Equipment: Process Turbidimeter

Model No: Micro TOL

I, the undersigned, hereby declare that the equipment specified above conforms to the

above Directive and Standard

Place: Fort Myers, Florida USA

(Signature)

Robert J. Maley, President

MICRO TOL (12/04)

REV. 2.7

MICRO TOL (12/04)

REV. 2.7

Table of Contents

Specifications.................................................................................................................1

1.0 Overview............................................................................................................2

1.1 Unpacking and Inspection of the Instrument and Accessories .............2

1.2 The Display ...........................................................................................2

1.3 The Touch Pad ......................................................................................3

1.4 Vapor purge ...........................................................................................4

2.0 Safety .................................................................................................................5

3.0 Installation and Commissioning .......................................................................6

3.1 Mounting and Site Selection..................................................................6

3.2 Plumbing ..............................................................................................7

3.2.1 Pressurized Systems...................................................................8

3.2.2 Drain Vent..................................................................................8

3.3 Electrical Connections ..........................................................................8

3.3.1 Power ........................................................................................9

3.3.2 RS-485 Option ..........................................................................9

3.3.3 Relays.........................................................................................9

3.3.4 4-20 mA ....................................................................................9

4.0 Operation .........................................................................................................10

4.1 Routine Measurement .........................................................................10

4.2 Security Access Feature.......................................................................11

5.0 Instrument Calibration ....................................................................................12

5.1 Calibration Standards ..........................................................................12

5.2 Calibration Procedures ........................................................................12

6.0 Instrument Offset ........................................................................................... 15

6.1 Indexing Calibration Cuvettes ............................................................16

6.2 Restoring Factory Settings...................................................................16

7.0 Instrument Configuration (CONFIG mode) ....................................................17

7.1 Displayed Resolution ..........................................................................17

7.2 Setting the Year....................................................................................17

7.3 Setting the Day and Month .................................................................18

7.4 Setting the Time...................................................................................18

7.5 Programming the Alarms & 4-20 mA (if used) ..................................19

7.5.1 Alarm 1 ....................................................................................20

7.5.2 Alarm 2 ...................................................................................21

7.5.3 Setting the 4-20 mA Output (O/P) ..........................................21

7.6 Configuring the RS-485 I/O Port (if equipped)...................................22

7.7 Setting the Security Access..................................................................25

7.8 Saving Configuration Settings.............................................................25

8.0 Troubleshooting & Maintenance ....................................................................26

8.1 Micro TOL Fault Detection.................................................................26

8.2 System Fail Message ...........................................................................26

8.3 Diagnostic Chart .................................................................................27

8.4 Technical and Customer Assistance ...................................................27

MICRO TOL (12/04)

REV. 2.7

Table of Contents (continued)

9.0 Routine Maintenance.......................................................................................28

9.1 Cleaning the Flow Through Cuvette ...................................................28

9.2 Replacing or Installing the Desiccant Pouch ......................................28

9.3 Replacing the Source Lamp ................................................................29

9.4 Replacing the Battery ..........................................................................29

10.0 Accessories and Replacement Parts List .........................................................29

11.0 Warranty .........................................................................................................30

MICRO TOL (12/04)

REV. 2.7

Specifications

Measurement Range

Accuracy

Resolution

Response Time 0 - 8 Seconds (0 – 10 NTU Range)

Display Multi-Line Liquid Crystal Display

Two User Programmable

Alarms & Analog Output

Communications Port

Maximum Water Pressure 414 kPa (60 psi.)

Flow Rate 100 ml/min. – 6 liters/min. (.026-1.5 Gal/min)

Operating Temperature Range

.01 – 1000.0 NTU
±2% of reading plus 0.01 NTU (0-10 NTU)

±5% of reading plus 0.1 NTU (10-1000 NTU)

0.0001 NTU (below 10 NTU)

0 – 20 Seconds (0-1000 NTU Range)

120-240VAC 2A Form C Relay & 4-20 mA

Bi-directional RS-485 (optional)

1°C – 50°C (34°F – 122°F)

Sample Temperature Range 1°C – 50°C (34°F – 122°F)

Power Supply Voltage 90 – 250 VAC, 47 – 63 Hz

Power Consumption 80 VA

Insulation Rating Double Insulated, Pollution Degree 2, Overvoltage Category II

Environmental Conditions Not recommended for outdoor use.

Altitude up to 2000 meters

Up to 95 % RH (non-condensing)
Enclosure Rating IP 66 /NEMA 4X
Regulatory Compliance
(0-10NTU)

Shipping Weight
Warranty 1 Year from date of shipment

(20023) White Light Version compliant to U.S. EPA 180.1

(20024) Infrared Version compliant to ISO 7027

2.5 kg (5.5 lbs.)

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1.0 Overview

The MICRO TOL process turbidimeter allows you to measure the turbidity of your
process water on-line. The White Light MICRO TOL has been designed to meet the
design criteria specified by the US EPA on turbidity measurement. The infrared MICRO
TOL was designed to meet the design criteria specified in ISO 7027 and DIN 27027 for
the measurement of the turbidity of a sample. Both models have long life lamps.

1.1 Unpacking and Inspection of the Instrument and Accessories

The table below indicates the items you should find in your turbidimeter shipment.

Item Part # Quantity

MICRO TOL Turbidimeter 20023 (White Light Version), or

20024 (Infrared Version)

Instruction Manual 24031 1

Desiccant Pouch 21555R 1

Cuvette (Single Pack) 50033 1

Tubing Kit * 51025A 1

* Note - Tubing Kit includes:
1-shutoff clamp
1-backpressure valve
2-connecting tubings with fittings for flow through assembly
1-drain vent screw (used in pressurized systems)

Remove the instrument from the packing carton. Carefully inspect all items to ensure
that no visible damage has occurred during shipment. If the items you received do not
match your order, please immediately contact your local distributor or the HF scientific,
inc. Customer Service department.

1

1.2 The Display

Figure 1 illustrates all the items that can appear on the display. The upper row of the
display (1) is used for reporting the turbidity levels and to provide user guidance in the
customer setting routine. The lower row of the display (2) is used to communicate error
messages and provide user guidance. The display has two icons (3) that are used to
indicate the use of access code and offset mode. In addition, mode arrows (4) are used to
indicate the current instrument operating mode; AUTO (normal operation), CAL
(calibration) and CONFIG (configuration).

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Figure 1 – Display used in the instrument.

All items used on the display are shown in this figure

1.3 The Touch Pad

Figure 2: The Micro TOL touch pad.

Figure 2 illustrates the touch pad. The touch pad has four buttons: MODE/EXIT, ↵, t,
and u. The MODE/EXIT button is used to cycle between the four operational modes of
the instrument: CAL, CAL OFFSET, CONFIG, and AUTO (Measurement) mode. The
↵ button enters the option (or mode that is highlighted or chosen. The tand u buttons

are used to scroll through lists and to increase or decrease settings.

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1.4 Vapor purge

The Micro TOL is equipped with a continuous vapor purge system. A replaceable
desiccant pouch in the lower portion of the instrument dries the air. System heat is used
to warm the air. A fan inside the instrument continuously circulates heated dry air around
the optical well and the flow through cuvette. This feature eliminates the need for a dry
purge line.

The Micro TOL monitors the replaceable desiccant pouch condition continuously. The
LCD display will show DESC on the lower line in the event that the desiccant pouch
needs replacement. Replacement desiccant pouches are available from HF scientific, inc.
or your local representative (part # 21555R).

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2.0 Safety

This manual contains basic instructions that you must follow during the commissioning,
operation, care and maintenance of the instrument. The safety protection provided by

this equipment may be impaired if it is commissioned and/or used in a manner not
described in this manual. Consequently, all responsible personnel must read this manual

prior to working with this instrument.
In certain instances Notes, or helpful hints, have been highlighted to give further

clarification to the instructions. Refer to the Table of Contents to easily find specific
topics and to learn about unfamiliar terms.

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3.0 Installation and Commissioning

Prior to use for the first time, the supplied desiccant pouch will need to be installed. Refer
to section 9.2 Replacing or Installing the Desiccant Pouch.

3.1 Mounting & Site Selection

The instrument is designed for wall mounting. If wall mounting is not practical, the
instrument can be mounted on any suitable level surface. For ease of service there should
be about 20 cm (8”) free area above the instrument; this will ensure enough room for
calibration and cuvette maintenance. Choose a location that is easily accessible for
operation and service and ensure that the front display rests at eye level. The overall
mounting dimensions of the instrument are shown in Figure 3. The recommended
mounting screws are M6 (¼”) for the instrument enclosure and M4 (3/16”) for the
junction box. The Micro TOL is designed to have the field terminal box cradled under the
sensor portion of the instrument. It is recommended that the field terminal box be
mounted first, and then the rest of the instrument be mounted on top.

It is critical that the instrument be mounted as close as possible to the sampling point to
ensure a quick response time (within 2-3 meters (6-10 ft) of the sampling point).

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Rev. 2.7

Figure 3: Overall Mounting Dimensions of the Instrument

6

3.2 Plumbing

The recommended plumbing for the instrument is shown in Figure 4. The instrument is
designed to require very little head pressure to operate. The flow through cuvette is rated
for a flow of 100ml/min. – 6 liters/min. (0.26-1.5 Gal/min), and a maximum pressure of
414 kPa (60 PSI.). The maximum allowable fluid temperature is 50°C (122°F).

Figure 4: Recommended Plumbing for the Instrument

The instrument is equipped to be plumbed using 4.75 mm (3/16”) ID, 8 mm (5/16”) OD
flexible tubing. Opaque tubing should be used if the tubing will be exposed to sunlight,
to prevent algae growth.

In figure 4, there are two flow devices shown. The one on the input side is a shutoff
clamp used during cuvette maintenance. The other device is a backpressure valve.
Backpressure may be required to prevent air from coming out of solution, which may be
observed as tiny air bubbles.

The instrument is equipped with an internal foot valve, which opens in case the flow
through cuvette ruptures, to prevent damage to the sensor. The stem of the emergency
drain can be connected to a 16 mm (5/8”) tube (not supplied) to direct the flow of water
to a convenient drain. Keep the length of this emergency drain to a minimum.

Note: The foot valve system can handle up to 1.5 liters per minute (0.4 gallon per minute).

Flow rates higher than this will cause the instrument to flood in the event of a
ruptured cuvette.

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3.2.1 Pressurized Systems: For pressurized systems, keep the pressure below 69 kPa (10

PSI) or 7.62 m (25 foot) of head or limit the flow the 1 liter per minute. An inline flow
regulator is available from HF scientific inc. catalog number 19778.

3.2.2 Drain Vent: The Micro TOL has been fitted with a drain vent in the “OUT”

bulkhead fitting. This fitting allows for atmospheric equalization, thus helping to alleviate
bubble formation in the cuvette.

In high-pressure systems, minor leakage may occur. This will subside once normal flow

is established.

For systems, where the “OUT” line does not return to an open drain, a 6:32 seal screw is

provided which should be inserted into the vent hole and tightened.

3.3 Electrical Connections

All of the electrical connections to the instrument are made through the field terminal
box, which should be located under the sensor section of the instrument. The connections
are labeled within the terminal box and are self-descriptive (see Figure 5). Please follow
all local and government recommendations and methods for installation of electrical
connections to and between the instrument and other peripheral devices.

Plugs are inserted into the alarm and 4-20mA/RS-485 cable bulkheads when shipped, to
ensure a watertight seal. These plugs should be removed and discarded when cabling to
either of these connections.

The power cable bulkhead will accept cable diameters from 5.8mm (.230 in.) up to 10
mm (.395 in.). All terminals are designed to accept wires in the range of 14-28 AWG.
All wires should be stripped to a length of 6 mm (¼”). A strain relief strap is provided to
reduce tension on the power terminals.

It is the user’s responsibility to assure that the watertight seal is maintained after the
terminal box has been wired for operation. If any of the bulkheads are not tightened
properly around a cable or plug, the ratings of the instrument will be jeopardized and
there is a possibility of creating a shock hazard.

Note: Only qualified electricians should be allowed to perform the installation of the

instrument as it involves a line voltage that could endanger life.

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Figure 5: Electrical Connections for the Instrument

3.3.1 Power: The instrument is equipped with a 90-250 VAC, 47-63 Hz switching power

supply; please verify that the line voltage falls within these specifications. It is
recommended that a circuit breaker be placed prior to the power connection to allow for
service. While making your connections, refer to Figure 5. The Micro TOL is not

supplied with a power cord.

Note: Your Micro TOL is equipped standard with a 4-20 mA output and alarm relays. If

the optional RS-485 is installed, the 4-20 mA and the relays are disabled and you
should ignore all references to these items.

3.3.2 RS-485 Option: (Part # 19615) The RS-485 half-duplex (2-wire) digital interface

option operates with differential levels that are not susceptible to electrical interferences.
This is why cable lengths up to 3000 ft can be implemented. The last device on every
bus must be terminated with a 120 ohm resistor to eliminate the possibilities of signal
reflection on the line. Do not run RS-485 cables in the same conduit as power.

Ensure each instrument is not powered when connecting the RS-485 line. To prevent
damage to the instrument, ensure that power is disconnected prior to making connections.

3.3.3 Relays: The Alarm 1 and Alarm 2 relays are mechanical relays rated at 240 VAC
2A. Please note that the relays are labeled NO (Normally Open), NC (Normally Closed)
and C (Common). As these alarms are configured fail-safe, the normal condition is with
power applied to the Micro TOL and in a non-alarm condition. Operation of these alarms
is covered in section 7.5 Programming the Alarms & 4-20 mA(if used).

3.3.4 4-20 mA: The 4-20 mA output is driven by a 12 VDC power source and can drive
recorder loads up to 450 ohms. This 4-20 mA output is isolated from line power and earth
ground. Do not run 4-20 mA cables in the same conduit as power. Operation of these
alarms is covered in section 7.5.3 Setting the 4-20 mA Output (if used). Optional optically
isolated outputs are available.

Ensure each instrument is not powered when connecting the 4-20 mA. To prevent
damage to the instrument, ensure that power is disconnected prior to making connections.

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4.0 Operation

This process turbidimeter allows you to measure the turbidity of your process water on­line. The turbidity of the process water is reported in Nephelometric Turbidity Units
(NTU). Readings above 1000 NTU are outside the range of this instrument.

During normal operation, the instrument will have the arrow beside AUTO highlighted
with the current scale displayed on the lower row of the display and the measured reading
on the upper row of the display (see illustration below).

In certain instances, during normal operation, the instrument will display a row of dashes
across the upper row of the display (see illustration below).

This indicates that either the instrument is performing an auto-ranging function, or the
sample has a substantial amount of bubbles. If the dashes remain for an extended period
of time, please remove the flow through cell and check the sample for a large amount of
bubbles present. If the problem persists, please contact the HF scientific, inc. Technical
Services Department for further assistance and guidance.

4.1 Routine Measurement

The following steps describe how to measure the turbidity of a sample using this
instrument:

1. Apply power to the instrument and allow the unit to warm up (typically 45 minutes –
1 hour on initial commissioning).

2. When a continuous process stream is flowing through the instrument, the instrument
will display the measured turbidity level of the sample by displaying it on the LCD
screen. In addition, the equivalent signal is provided on the analog (4-20 mA) output,
or the digital output, depending on the options selected.

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4.2 Security Access Feature

The instrument is equipped with a security access code feature that can be activated in the
configuration mode. If the security feature is enabled, the screen shown in the illustration
below will appear when you press the MODE/EXIT button.

The security code has three numbers that are selectable one at a time. Notice that the first
number in the code is flashing; the flashing indicates that this is the number to be

changed. Use the tor u arrows to select the value of the first of the three numbers in
the code and then press the ↵ button to accept the first number of the code. Now enter
the second number in the code. Proceed as with the first number followed by ↵. Then
repeat the process for the third number in the access code, remember to finish with the ↵

button.
If you have selected the valid access code, the instrument will be directed to the

calibration mode. If the wrong access code is selected, the instrument will return to the
AUTO mode. Refer to section 7.7 Setting the Security Access for more information.

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5.0 Instrument Calibration

The instrument was calibrated and tested prior to leaving the factory. Therefore, it is
possible to use the instrument directly out of the box. Under normal conditions, re­calibration is recommended at least once every three months1. If calibration is not
performed, the instrument will continue to monitor the turbidity of the process water with
a decreased accuracy.

Relay contacts are held at the last valid condition and will not change state while the
instrument is in the calibration and/or in the configuration mode. While in the calibration
mode, the instrument has a time-out feature that automatically returns the system
operation to the AUTO mode after a thirty (30) minute period of inactivity.

5.1 Calibration Standards

If the Micro TOL will be used over the entire range of .02 to 1000 NTU a complete
calibration as described below will be required. If instrument accuracy is only required
below 10 NTU, such as potable water, a calibration may be performed using only a 10

NTU and a 0.02 NTU standard. To calibrate starting at the 10 NTU, press the tbutton
to bypass the 1000 NTU and proceed to Section 5.2 Calibration Procedures, step 5. Note
that using the t and u buttons you can rotate through the requested standards and get to
the END prompt. Pressing the ↵ button at the END prompt will have the same affect as

pressing the MODE/EXIT button; no calibration change will have been made.
We recommend that you use the following materials during calibration to achieve the
full-scale accuracy stated in this manual:

1. 0.02 NTU Calibration Standard available from HF scientific inc.

2. 10.0 NTU Calibration Standard available from HF scientific, inc.

3. 1000 NTU Calibration Standard available from HF scientific, inc.

It is well known that diluted Formazin is unstable. If you choose to use Formazin to
calibrate the instrument, ensure that you are using a fresh stock suspension of Formazin
to achieve the accuracy quoted for the instrument. A Formazin Stock Solution Kit is
available from HF scientific, inc. (Catalog No. 50040). The HF scientific, inc. ,
primary calibration standards (refer to section 10.0 Accessories and Replacement Parts
List) are more stable than Formazin and have a minimum shelf life of 12 months. Prior to
recalibration, review the expiration dates, to ensure that the standards have not expired.

5.2 Calibration Procedures

1. Select the calibration function of the instrument by pressing the MODE/EXIT button
once. The arrow beside CAL will be illuminated on the display. The lower display
shows alternating 1000 (the value of the standard that is requested) and ↵. The upper
display shows the real-time reading to allow the standard to be indexed. Refer to
section 6.1 for information on indexing cuvettes.

1

The EPA recommends that on-line turbidimeters be calibrated with a primary standard at least once every three

months if they are to be used for EPA reporting.

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2. Remove the flow through unit.

3. Insert the requested 1000 NTU standard. Index the standard to the lowest value on the
upper display.

4. Press the ↵ button to accept the calibration.

5. The lower display will count down the progress of the calibration step.

6. The lower display will now change to show alternating 10 and ↵, requesting the 10.0
NTU standard.

7. If the alternating 10 and ↵ is not displayed, push the t or uuntil you get this
display.

8. Insert the requested 10.0 NTU standard. Index the standard to the lowest value on the
upper display.

9. Press the ↵ button to accept the calibration.

10. The lower display will count down the progress of the calibration step.

11. The lower display will now change to show 02 and ↵, requesting the 0.02 NTU
standard.

12. Insert the requested 0.02 NTU standard. Index the standard to the lowest value on the
upper display.

13. Press the ↵ button to accept the calibration.

14. The lower display will count down the progress of the calibration step.

15. The instrument will show alternating END and ↵.

16. Press the ↵ button to accept the calibration.

17. The instrument will display SAVE on the lower display briefly and then the Mode
will return to AUTO.

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Note: During calibration, the fan inside the instrument is turned off to extend the life of

the desiccant. The fan will be turned on after returning to the AUTO mode or after
five minutes, which ever comes first. It is recommended that the measurement
chamber be kept covered during the calibration period and that the flow through
cuvette be replaced immediately after the calibration to prevent premature
contamination of the desiccant.

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6.0 Instrument Offset

In certain instances, you may wish to use an offset factor to calibrate your instrument
rather than performing a physical calibration of the instrument (as described in section

5.2). This procedure is not recommended in lieu of regular instrument calibration but it

can be used in situations where the number of instruments used makes regular calibration
prohibitive. This calibration technique will make the instrument accurate only at
turbidity levels in the immediate vicinity of the grab sample and not in the full range of
the instrument. Note that the key icon will be illuminated whenever an offset used. The
maximum offset is ± 1.00 NTU. If instrument variation is greater than 1 NTU a full
calibration is recommended.

The procedures are as follows:

1. Collect a grab sample of the process water that is being monitored by the instrument
and record the turbidity reported by the instrument.

2. Take the grab sample and measure its turbidity using your laboratory turbidimeter
(contact the HF scientific, inc. customer services department for examples of
laboratory turbidimeters).

3. Compare the turbidity reported by the instrument to that obtained in your laboratory.
If the readings are very close, then no offset adjustment or calibration is required and
you may stop the procedure at this step. However, if the readings are substantially
different (but less that 1 NTU), you may continue on in this procedure to utilize the
offset option to improve the turbidity reading of the instrument so that it will agree
with your laboratory reading between calibrations.

4. Select the calibration-offset function of the instrument by pressing the MODE/EXIT
button until the OFFSET and the arrow beside CAL are illuminated on the display.
Refer to the following screen.

5. At this point, the lower row of the display will indicate the operational status of the
offset function (ON or OFF). You may change this status by using the t and u

buttons. Once you have set the desired operational status of the offset function press

↵ button to accept it. If you turned the option off, you can return to AUTO mode

the
by pressing MODE/EXIT.

6. If you turned the option ON, you will be prompted to enter the offset required. This
will add or subtract the value of the offset to the measured NTU value. As an example
if the Micro TOL measures the process at 0.16 NTU but the laboratory instrument
read the sample at 0.12 NTU, adding an offset of –0.04 would result in the Micro
TOL displaying 0.12 NTU.

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Select the desired offset level using the t and u buttons. Once you have set the
desired level, press the ↵ button to accept it.

7. This completes the offset configuration.

8. At this point, the instrument will continue to the configuration (CONFIG) mode of
the instrument or press MODE/EXIT to return to the AUTO mode.

6.1 Indexing Calibration Cuvettes

To achieve the greatest accuracy, and account for normal scratches and aberrations in
cuvette glass when calibrating, HF scientific inc. recommends indexing the cuvettes.

Each instrument is supplied with a white Indexing Pin located in the collar around the
optical well. Standards and standard kits purchased from HF scientific are supplied with
indexing rings.

The following two steps allow repeatable indexing of calibration standards:

1. Slowly rotate the standard, inside the optical well, one complete revolution (360º).
While rotating the standard slowly, observe the measured turbidity and locate the
position of the cuvette having the lowest reading.

2. With the calibration standard positioned at the location having the lowest turbidity
reading, install the Indexing Ring over the black light shield on the standard so that
the pointer of the Indexing Ring aligns with the Indexing Pin.

6.2 Restoring Factory Settings

If the instrument is unable to perform a calibration due to a low lamp output or a
calibration using the wrong standards, the instrument will display CAL on the lower row
of the display. The operator has two choices to correct this problem. If the operator can
determine whether a poor calibration or a low lamp caused the problem, he/she can
remedy the problem and recalibrate. If all else fails, the operator may restore the factory
calibration by performing the following operation. While in the AUTO mode, Push and
hold the tbutton. Now push and release the ↵ then thetbutton. Factory calibration and
factory configuration have now been restored.

Note: Restoring the factory settings allows the use of the Micro TOL with reduced

accuracy. The original problem still exists and must be determined and corrected
before accurate operation of the Micro TOL will be resumed.

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7.0 Instrument Configuration (CONFIG mode)

The instrument has been designed to provide you with the ability to customize your
instrument according to your needs at any time during normal operation. This mode has
been split into sub-menus to facilitate instrument configuration. This section describes
how you can use each of the sub-menus to configure your instrument

Enter the CONFIG mode of the instrument by pressing the MODE/EXIT button until the
arrow beside CONFIG is illuminated, then press the ↵ button.

Note: To skip the selection of the CONFIG mode, press the MODE/EXIT button.

7.1 Displayed Resolution

The instrument is equipped with the ability to display several levels of resolution. The
instrument can display up to four digits to the right of the decimal place for turbidity
readings below 10 NTU. If you feel that the last digit or two is not stable then you may
adjust the resolution to hide these digits. Upon entering the CONFIG mode, the lower
row of the display will show RES and the upper row of the display will show the number
of digits that will be displayed.

Change the resolution by pressing the t or u button. When you have selected the
desired digit resolution press the ↵ button. After pressing the ↵ button, the word YEAR

will appear and the current year will be displayed.

7.2 Setting the Year

With the YEAR showing and the year displayed, change the displayed year using the t
or u buttons. When you have selected the proper year press the ↵ button to accept the

year.

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7.3 Setting the Day and Month

After pressing the ↵ button, MNTH will be displayed and you will see a number
corresponding to the month.

Set the correct month by pressing the t or u button to change the displayed month.
When you have selected the proper month, press the ↵ button. After pressing the ↵
button, DAY will be displayed and you will see a number corresponding the day of the

month.

Set the correct day by pressing the t or u buttons to change the displayed day. When
you have set the proper day, press the ↵ button.

7.4 Setting the Time

After pressing the ↵ button, HOUR will be displayed and you will see the time displayed
on the LCD screen in 24-hour format corresponding to the hour.

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Set the correct hour by pressing the t or u button to change the displayed hour. When
you have selected the proper hour, press the ↵ button. After pressing the ↵ button, MIN

will be displayed and you will see the current minute of the hour.

Set the correct minute by pressing the t or u button to change the displayed minutes.
When you have set the correct minute, press the ↵ button.

7.5 Programming the Alarms & 4-20 mA (if used)

If your instrument does not use the RS-485 option, the following menus will be displayed
after the date and time.
Two relays are provided that are designed to operate as two independent programmable
alarms. You must input three types of information to fully program each alarm:

1. The alarm function (HI, LO, or OFF)

2. The alarm set point (level at which the alarm activates)

3. The delay time for the alarm: the time that the set point must be exceeded prior to
alarm activation (prevents ringing in the relay)

These three items are described below:

Alarm Function: The alarms can either be turned OFF or programmed to operate in one
of two different manners:

1. HI alarm: the relay changes state when the measured turbidity level is higher than the
programmed alarm level for a prescribed amount of time.

2. LO alarm: the relay changes state when the measured turbidity level is lower than the
programmed alarm level for a prescribed amount of time.

Note: The relays automatically change state when an internal system failure is detected.

Alarm Set Point: The level at which an alarm activates is called the alarm set point. On

the instrument, the alarm set point is designated as “S/P”. The set point is adjustable to
any valid turbidity level over the range of the instrument in steps of 0.01 NTU.

Alarm Delay Time: The alarm delay times are used to prevent ringing of the alarm
when the measured turbidity level is close to the set point. The function of the delay
times is as follows:

Delay On: The turbidity level must exceed the alarm set point continuously for at

least this number of seconds before the alarm activates.

If the delay on time is set at 5 seconds and the process turbidity exceeds the
set point continuously for only 4 seconds, the alarm will not be activated.
However, process turbidity exceeds the set point continuously for 5 seconds or
more, the instrument will activate the alarm.

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Delay Off: The turbidity level must not exceed the alarm set point continuously for at

least this number of seconds prior to deactivation of the alarm.

If the delay off time is set to 5 seconds and the process has exited out of the
alarm condition, the alarm will be reset only if the process is out of the alarm
condition for a continuous 5 seconds. Otherwise, the instrument will still
signal an alarm condition.

7.5.1 Alarm 1

Alarm 1 Function: The ALM1 is displayed and the display indicates the current

function of alarm 1 (HI, LO, or OFF). You can use the toru buttons to cycle through
and select the desired function. Press the ↵ button to accept your selection.

If you selected to turn the alarm OFF, you will be immediately prompted to set up alarm
2 (go to section 7.5.2). If, on the other hand, you selected one of the other functionalities
you will be prompted to set the delay times.

Alarm 1 Set Point: You will be prompted to select the set point for this alarm; this is
indicated by “S/P” shown on the lower row of the display. You can select the desired
alarm level by using the t and u buttons. Once you have set the desired set point, press
the ↵ button to accept it.

Alarm 1 Delay Times: Delay On: The following display will appear to allow you to
select the number of seconds currently set for the “delay on” time.

The current selected number of seconds will be shown. You can select the desired
number of seconds for the “delay on” time for this alarm using the t and u buttons.
Once you have set the desired delay time, press the ↵ button to accept it.

Delay Off: Next, the following display will appear to allow you to select the number of
seconds currently set for the “delay off” time.

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The current selected number of seconds will be shown. You can select the desired delay
off time for this alarm using the t and u buttons. Once you have set the desired delay
time, press the ↵ button to accept it. After you complete the settings for alarm 1 you will

be prompted to set up information on alarm #2.

7.5.2 Alarm 2

Repeat the procedure listed in section 7.5.1 to set up the parameters for alarm 2. If you
select to turn the alarm OFF, you will be immediately prompted to set up the 4-20 mA
output (see section 7.5.3 below). If, on the other hand, you selected one of the other
functionalities you will be prompted to set the delay times and the set point as with Alarm
#1.

Once you complete the selections for Alarm #2 you will be prompted to set up the analog
output.

7.5.3 Setting the 4-20mA Output (if used)

The output (O/P) selection allows you to turn the 4-20 mA analog output on (4-20), or off
(OFF). You can select the desired analog output operation using the t and u buttons.
Once you have set the desired operation, press the ↵ button to accept it.

If you selected to turn the 4-20 mA output on, you will be prompted to set the lower
(LOLM) and upper (UPLM) turbidity limits corresponding to the 4 mA and 20 mA
output levels. First, you will be prompted with the turbidity limit assigned to the 4 mA
output level:

Select the turbidity level you wish to assign to the LOLM using the t and u buttons.

Once you have set the desired level, press the ↵ button to accept it.
Next, you will be prompted with the turbidity level assigned to the 20 mA output level

(UPLM on the lower row of the LCD display).

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Select the turbidity level you wish to assign to the UPLM using the t and u buttons.
Once you have set the desired level, press the ↵ button to accept it. The next prompt will

be for the access code. Refer to section 7.7 Setting the Security Access Option.

7.6 Configuring the RS–485 I/O Port (if equipped)

If your instrument is equipped with the option, the following menus will be displayed
after the date and time.

Automatic/Timed Printouts: After pressing the ↵ button, PRNT will be displayed. The
Upper row of the display will indicate whether this option is turned ON or OFF. Turn
ON to select timed printouts.

Next, select the printing interval. This is the interval at which the instrument will print
out the instantaneous turbidity level, time, and date. Your choices are 1 HOUR, 4
HOUR, 8 HOUR, 15 MIN & 30 MIN. Use thet or u button to change and the ↵
button to select. You will then be requested to select the BAUD.

Note: The timing for the interval starts at midnight.

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Select the correct baud rate (1200, 2400, 4800, or 9600) for operation of the I/O port by
pressing either the t or u button to change the displayed baud rate. When you have
selected the proper baud rate press the ↵ button to continue on to 7.7 Setting the Security

Access Option. The communication parameters are 8 bits, no parity and 1 stop bit.

Note: The information printed out in the timed printout has the format: x.xx NTU dd mm

yyyy hh:mm. The resolution of the turbidity level output is the same as the
resolution of the turbidity level on the display.

Bi-Directional Communication: The instrument is equipped with the ability for bi-

directional communication. This means that a remote unit can prompt the instrument to
send out the current turbidity levels via the RS-485. If the timed print option was turned
OFF, the next prompt will be for the address of the Micro TOL.

Here you can select the desired instrument address (1-255) using the t or u buttons.
Once you are satisfied you can press the ↵ button to select. You will then be requested to
select the BAUD.

Select the correct baud rate (1200, 2400, 4800, or 9600) for operation of the I/O port by
pressing the t or u buttons to change the displayed baud rate. When you have selected
the proper baud rate press the ↵ button to continue on to 7.7 Setting the Security Access

Option. The communication parameters are 8 bits, no parity and 1 stop bit.

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Communication Protocol: The originating instrument (master) has a designated address
of 00 hex and each instrument has a designated address from 01 hex to FF hex. The
communication protocol is as follows: the master computer will send out a 5 BYTE
instruction to the instrument to request data and the correct instrument will respond with
a 18 BYTE return message. To ensure a smooth transition of information each
instrument is designed with a 100-200 ms hang up time: the instrument waits 100-200 ms
before switching from receive to transmit to send the information to the master computer.

The 5 BYTE message sent by the master computer is detailed as follows:

 BYTE #1 is an attention character (3A in hex format)
 BYTE #2 is the native address of the master instrument that is requesting

information from the instruments in the RS485 loop. This address is 00 hex by
definition (sent in hex format).

 BYTE #3 is the address of the instrument being queried (sent in hex format)
 BYTE #4 is the command/request to be serviced. 00 hex is the request to have

the instrument report the current turbidity level (sent in hex format)

 BYTE #5 is the Check Sum of the previous 4 bytes (sent in hex format). Note

that 1 hex is added to the sum as an offset level.

When a command of 0 hex is issued by the master computer, the instrument that was
addressed will provide an 18 BYTE return message. This message is detailed as follows:

 BYTE #1 is an attention character (3A in hex format)
 BYTE #2 is the native address of the instrument that is responding (sent in hex

format).

 BYTES #3-10 represent the current turbidity value (including decimal place) sent

in hex. All hex values should be converted to ASCII. Any unused bytes
(depending on selected resolution) are filled to the right with spaces (20 hex).

 BYTES #11-13 represent the engineering units measured with this instrument:

‘NTU’ (sent in hex format). All hex values should be converted to ASCII.

 BYTES #14-15 represent the instrument status WORD in hex format (high BYTE

first). This provides information on the mode that the instrument is currently in.

 BYTES #16-17 represent the instrument warning status WORD in hex format

(high BYTE first). This status WORD provides detailed information on warnings
that the instrument has stored. If this WORD is 0 hex then the instrument is
operating with no warnings or problems observed in operation.

 BYTE #18 is the Check Sum of the previous 17 bytes (sent in hex format). Note

that 1 hex is added to the sum as an offset level.

The Baud rate used in this feature is the same as the baud rate set in the previous section
on automatic/timed printouts. The other parameters for the digital communication are 8
bit, no parity and one (1) stop bit.

An optional PC software package, called HF ONLINE (HF catalog # 19783) allows for
an interface with up to 255 Micro TOL’s for the purpose of data logging. This package is
similar to a small SCADA system and operates by communicating over the interface.

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7.7 Setting the Security Access

The instrument is equipped with a security access. If this option is turned on, the user is
required to input the access code into the instrument to get to any mode other than
AUTO. The only code is 333. This code may not be changed. See section 4.2 for more
information on this security feature. The security key icon will be visible and flashing on

the display whenever the access option is selected using the t or u buttons. (ON or
OFF).

7.8 Saving Configuration Settings

Once you have set the desired security code functionality, press the ↵ button to accept it.
You will now see a screen with the word SAVE on the lower row of the display,
indicating that your settings were saved. The Micro TOL will automatically return to the
normal AUTO mode of the instrument.

You can enter this menu at any time to reset or change any of the parameters. You can
exit at any point in the menu by using the MODE/EXIT key. Any features that you have
modified will be saved.

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8.0 Troubleshooting & Maintenance

8.1 Micro TOL Fault Detection

The Micro TOL performs continuous diagnostic monitoring. In the Micro TOL there are
three levels of fault detection; warnings, errors and failures.

A warning indicates that there is a system problem that does not interfere with the
operation of the instrument and can be corrected by the operator. These warnings consist
of 4-20 mA loop open (MA) if equipped, and desiccant replacement required (DESC). At
this level of fault there is only a screen display indicating the problem.

An error indicates a failure or a problem that does interfere with the operation but can be
corrected by the operator. These errors consist of lamp out (LAMP) & no flow (FLOW)
(if equipped with the flow switch). If any of these conditions occurs, both alarm relays (if
equipped) will be activated and the 4-20 mA output will be held at 2 mA (if equipped). If
any of these errors occur the instrument will still display readings, however the accuracy
is not known and the instruments readings should not be trusted.

A failure is a system fault. This is NOT a problem that the operator can correct, and the
unit must be returned to the factory for service. These failures consist of failures in the
CPU, A/D, EEPROM or other devices internal to the instrument (FAIL). If a failure
occurs, the instrument will not operate. At best it will display the word FAIL on the lower
row and both alarm relays (if used) will be activated and the 4-20 mA output will be held
at 2 mA (if used).

If any fault conditions occur, the message indicating the fault will be shown on the lower
row of the display.

8.2 System FAIL Message

Normally, this condition indicates that the instrument will require servicing. Contact
either the HF scientific, inc. Technical Service Department or the HF scientific, inc.
Customer Service Department.

HF scientific, inc.

3170 Metro Parkway

Fort Myers, Florida 33916-7597

Phone: [phone]

Fax: [phone]

Email: [e-mail]

MICRO TOL (12/04)
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8.3 Diagnostic Chart

Symptom Cause Cure

Lower display shows MA
Lower display shows DESC
Lower display shows CAL

Lower display shows LAMP
Lower display shows FLOW
Lower display shows FAIL

Readings are higher than
expected

Readings are erratic

4-20 mA loop open Check wiring. See sections

3.3.4 and 7.5.3

Desiccant pouch bad Change desiccant pouch. See

section 9.2
Calibration failure Refer to sections 5 and 6.1
Lamp failed Replace lamp. Refer to section

9.3

Sample flow has stopped Restore flow. Contact HF about

factory installed option
Major system fault Refer to section 8.1 & 8.2

(1) Bubbles in solution

(2) Condensate or leaky

cuvette

(3) Flow through cuvette

dirty

Instrument out of calibration

(1) Bubbles in solution
(2) Debris in flow through

(1)Ensure that the drain vent is

open and is not obstructed.

See section 3.2.2.

(2)Apply backpressure. See

section 3.2 and figure 4

(3) For sever cases of bubbles a

stilling chamber is
available. Call HF scientific.

Part# 20106

Check flow through cuvette for

condensate or leaks.

Clean cuvette. See section 9.1

Recalibrate. Refer to section 5

(1) See above

(2) Clean debris from cuvette

Readings are lower than expected Instrument out of calibration Recalibrate. Refer to section 5
Upper display shows O-r Sample Over-Range Check sample. Must be over

1000 NTU.

8.4 Technical and Customer Assistance

If for any reason you need assistance regarding this instrument please do not hesitate to
contact either the HF scientific, inc. Technical Service Department or the HF scientific,
inc. Customer Service Department:

HF scientific, inc.

3170 Metro Parkway

Fort Myers, Florida 33916-7597

Phone: [phone]

Fax: [phone]

Email: [e-mail]

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9.0 Routine Maintenance

9.1 Cleaning the Flow Through Cuvette

Measurement cuvettes used for both grab sample and the flow though should be clean
and free of marks or scratches. Cleaning is accomplished by cleaning the interior and
exterior with a detergent solution and then rinsing several times with distilled or de­ionized water. The cuvette can be replaced by first shutting off the flow using the
provided shutoff clamp; unscrewing the old cuvette and replacing with a fresh clean one.

9.2 Replacing or Installing the Desiccant Pouch
The Micro TOL continuously checks the condition of the
desiccant tray. When the desiccant gets in such a condition
that it may cause problems, the instrument will display DESC
on the lower portion of the display.

Proper use of the supplied desiccant is essential in
maintaining the performance of the instrument. The desiccant
has been designed to have a long life; however, replacement
of the desiccant pouch will be required from time to time. It is
also essential that all enclosure seals be maintained. The
emergency drain and o-rings that are supplied with each new
instrument, form part of the instrument humidity seal. Inspect
these items each time the desiccant pouch is replaced.
Replace any parts found to be defective.

The desiccant should be replaced when the instrument
displays DESC. A new sealed desiccant pouch and indicator
card are available from HF scientific inc. part #21555R.To
initially install or remove the old desiccant, simply unscrew
the four corner thumbscrews and remove the electronics half
of the instrument. Open the bag protecting the new desiccant
pouch and replace (or install for a new instrument) in the
desiccant tray assembly.

Note: Once the bag is opened, install the desiccant pouch immediately.

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9.3 Replacing the Source Lamp

The source lamps in the Micro TOL’s are designed for long life. The IR lamp is rated for
10 years and the white light version is rated for 7 years. If your lamp should need
replacement, we recommend you call HF Customer Service Department for assistance.

9.4 Replacing the Battery

The Micro TOL uses a 10-year life lithium battery as a backup for the contained real-time
clock chip. This battery is non-rechargeable, but should last the life of instrument. Failure
of this battery does not disable the instrument, however some functions such as
automated print options will not function. This battery is not designed to be field
replaced. Exchange modules are available from HF scientific inc. Call HF Customer
Service Department for assistance.

10.0 Accessories and Replacement Parts List

The items shown below are recommended accessories and replacement parts.

Accessory

White Light Infrared

Calibration Kit, Low Range, .02 & 10 NTU 29953 19956

Calibration Kit, Full Range, .02, 10 & 1000 NTU 29957 19961
Formazin Stock Kit 50040 50040
Formazin Stock Solution, 4000 NTU, 500 ml 70914 70914
Replacement Desiccant Pouch 21555R 21555R
Electronic Service Module 19815 19815I
Operating Manual, Micro TOL 24031 24031
Software for data collection and reporting 19783 19783
Flow Regulator, Micro TOL 19778 19778
Tubing Kit Containing:
1-shuttoff clamp , 1-backpressure valve, 2-connecting tubings with

fittings for flow through assembly, 1-drain vent screw.

To order any accessory or replacement part, please contact the HF scientific, inc.
Customer Service Department. If for any reason you need technical assistance regarding
this instrument please do not hesitate to contact the HF Technical Services Department.

HF scientific, inc.

3170 Metro Parkway

Fort Myers, Florida 33916-7597

Phone: [phone]

Fax: [phone]

Email: [e-mail]

Catalog Number

51025A

51025A

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11.0 Warranty

HF scientific, inc., as vendor, warrants to the original purchaser of this instrument that it
will be free of defects in material and workmanship, in normal use and service, for a
period of one year from date of delivery to the original purchaser. HF scientific, inc.’s,
obligation under this warranty is limited to replacing, at its factory, the instrument or any
part thereof. Parts, which by their nature are normally required to be replaced
periodically, consistent with normal maintenance, specifically reagent, desiccant, sensors,
electrodes and fuses are excluded. Also excluded are accessories and supply type items.

Original purchaser is responsible for return of the instruments, or parts thereof, to HF
scientific, inc.’s factory. This includes all freight charges incurred in shipping to and
from HF scientific, inc.’s factory.

HF scientific, inc. is not responsible for damage to the instrument, or parts thereof,
resulting from misuse, environmental corrosion, negligence or accident, or defects
resulting from repairs, alterations or installation made by any person or company not
authorized by HF scientific, inc.

HF scientific, inc. assumes no liability for consequential damage of any kind, and the
original purchaser, by placement of any order for the instrument, or parts thereof, shall be
deemed liable for any and all damages incurred by the use or misuse of the instruments,
or parts thereof, by the purchaser, its employees, or others, following receipt thereof.

Carefully inspect this product for shipping damage, if damaged, immediately notify the
shipping company and arrange an on-site inspection. HF scientific, inc. cannot be
responsible for damage in shipment and cannot assist with claims without an on-site
inspection of the damage.

This warranty is given expressly and in lieu of all other warranties, expressed or implied.
Purchaser agrees that there is no warranty on merchantability and that there are no other
warranties, expressed or implied. No agent is authorized to assume for HF scientific, inc.
any liability except as set forth above.

HF scientific, inc.
3170 Metro Parkway
Fort Myers, Florida 33916-7597
Phone: [phone]

Fax: [phone]

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