Teledyne 452 User Manual

MODEL 452

PROCESS OZONE SENSOR

©Teledyne Instruments

Advanced Pollution Instrumentation Division

(T-API)

9480 Carroll Park Drive

San Diego, CA 92121-5201

TOLL-FREE: 800-324-5190

TEL: [phone]

FAX: [phone]

E-MAIL: [e-mail]

WEB SITE: www.teledyne-api.com

Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

SAFETY MESSAGES

NOTE

The M452 contains no user serviceable parts.

CAUTION

There is risk of dangerous UV exposure when the

cover is removed from the sensor. Take necessary

precautions to avoid exposure.

High voltages exist inside the sensor. Please use

caution when sensor cover is removed.

CAUTION

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

TABLE OF CONTENTS

SAFETY MESSAGES............................................................................I

TABLE OF CONTENTS ....................................................................III

LIST OF FIGURES...............................................................................V

LIST OF TABLES.................................................................................V

WARRANTY POLICY......................................................................VII

1 PRODUCT DESCRIPTIONS......................................................... 1-1

1.1 M452 PROCESS OZONE SENSOR .................................................. 1-1

1.2 M452 HIGH PURITY PROCESS OZONE SENSOR............................. 1-1

2 SPECIFICATIONS ......................................................................... 2-1

2.1 MECHANICAL SPECIFICATIONS .................................................... 2-1

2.2 PERFORMANCE SPECIFICATIONS .................................................. 2-2

2.3 OPERATING LIMITS ...................................................................... 2-2

2.4 ELECTRICAL SPECIFICATIONS ...................................................... 2-2

2.5 CALIBRATION REFERENCE........................................................... 2-2

2.6 PRESSURE DROP........................................................................... 2-3

2.7 OPTIONS....................................................................................... 2-4

2.7.1 AC Power Adapter............................................................... 2-4

2.7.2 Ozone Destructor (1/4” Tube Fittings)................................ 2-4

3 THEORY OF OPERATION .......................................................... 3-1

4 INSTALLATION............................................................................. 4-1

4.1 UNPACKING ................................................................................. 4-1

4.2 MECHANICAL INSTALLATION....................................................... 4-1

4.3 ELECTRICAL CONNECTIONS......................................................... 4-1

4.3.1 Power Supply....................................................................... 4-2

4.3.2 Analog Output...................................................................... 4-3

4.3.3 Zero Calibration Input......................................................... 4-3

4.3.4 Status Outputs...................................................................... 4-4

4.3.5 RS232/485 Interface ............................................................ 4-5

4.4 GAS CONNECTIONS...................................................................... 4-6

4.5 START-UP AND CALIBRATION PROCEDURE.................................. 4-7

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

5 SENSOR AND SYSTEM TROUBLESHOOTING ......................5-1

5.1 STATUS LED’S............................................................................. 5-1

5.2 STATUS OUTPUTS......................................................................... 5-2

5.3 SENSOR O.K.................................................................................5-2

5.4 INVALID READING........................................................................ 5-3

5.5 LAMP LOW...................................................................................5-3

5.6 CELL DIRTY .................................................................................5-4

5.7 STATUS OUTPUT SUMMARY TABLE ............................................. 5-4

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

LIST OF FIGURES

FIGURE 2-1: M452A HIGH PURITY OZONE SENSOR.............................. 2-1

FIGURE 2-2: PRESSURE DROP VS. FLOW (HIGH PURITY VERSION)........ 2-3

FIGURE 4-1: ELECTRICAL CONNECTIONS.............................................. 4-2

FIGURE 4-2: DIGITAL OUTPUT CONNECTIONS....................................... 4-4

LIST OF TABLES

TABLE 5-1: STATUS OUTPUTS............................................................... 5-2

TABLE 5-2: STATUS OUTPUT TRUTH TABLE ......................................... 5-4

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

WARRANTY POLICY

ADVANCED POLLUTION INSTRUMENTATION DIVISION

02024c

Prior to shipment, Teledyne API equipment is thoroughly inspected and
tested. Should equipment failure occur, Teledyne API assures its
customers that prompt service and support will be available.

COVERAGE

After the warranty period and throughout the equipment lifetime, Teledyne
API stands ready to provide on-site or in-plant service at reasonable rates
similar to those of other manufacturers in the industry. All maintenance
and the first level of field troubleshooting are to be performed by the
customer.

NON-API MANUFACTURED EQUIPMENT

Equipment provided but not manufactured by Teledyne API is warranted
and will be repaired to the extent and according to the current terms and
conditions of the respective equipment manufacturers warranty.

GENERAL

Teledyne API warrants each Product manufactured by Teledyne API to be
free from defects in material and workmanship under normal use and
service for a period of one year from the date of delivery. All replacement
parts and repairs are warranted for 90 days after the purchase.

If a Product fails to conform to its specifications within the warranty
period, Teledyne API shall correct such defect by, in Teledyne API's
discretion, repairing or replacing such defective Product or refunding the
purchase price of such Product.

The warranties set forth in this section shall be of no force or effect with
respect to any Product: (i) that has been altered or subjected to misuse,
negligence or accident, or (ii) that has been used in any manner other than
in accordance with the instruction provided by Teledyne API or (iii) not
properly maintained.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

THE WARRANTIES SET FORTH IN THIS SECTION AND THE
REMEDIES THEREFORE ARE EXCLUSIVE AND IN LIEU OF ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
PARTICULAR PURPOSE OR OTHER WARRANTY OF QUALITY,
WHETHER EXPRESSED OR IMPLIED. THE REMEDIES SET
FORTH IN THIS SECTION ARE THE EXCLUSIVE REMEDIES FOR
BREACH OF ANY WARRANTY CONTAINED HEREIN. TELEDYNE
API SHALL NOT BE LIABLE FOR ANY INCIDENTAL OR
CONSEQUENTIAL DAMAGES ARISING OUT OF OR RELATED TO
THIS AGREEMENT OF TELEDYNE API'S PERFORMANCE
HEREUNDER, WHETHER FOR BREACH OF WARRANTY OR
OTHERWISE.

TERMS AND CONDITIONS

All units or components returned to Teledyne API should be properly
packed for handling and returned freight prepaid to the nearest designated
Service Center. After the repair, the equipment will be returned, freight
prepaid.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

1 Product Descriptions

1.1 M452 Process Ozone Sensor

The Teledyne API M452 is a microprocessor-based sensor for measuring
the concentration of gaseous ozone in processes such as semiconductor
wafer fabrication, water treatment, and ozone research. The M452 can be
used as a full flow process sensor or as a sensor to monitor a small flow of
gas diverted from a process stream.

The M452 features a standard 0-5 volt analog signal for reporting process
concentration as well as 4 digital status outputs for sensor diagnostics. A
bi-directional serial interface is also provided for computer control.

The M452 operates from an external +15 vdc power source.

1.2 M452 High Purity Process Ozone Sensor

The M452A High Purity Process Ozone Sensor includes a 316L manifold
with a 10Ra finish. ¼” VCR face seal fittings are standard.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

2 Specifications

Note: All specifications contained herein are subject to change without
notice. Please contact Teledyne API to obtain the current specifications.

2.1 Mechanical Specifications

15 PIN "D" CONNECTOR

Model 452A

Electrical connections;
1 Analog out −
2 Analog out +
3 Ground
4 +15V in
5 +15V in
6 Digital in #1
7 Digital in #2
8 Digital out #1
9 Digital out #2
10 Digital out #3
11 Digital out #4
12 Digital out common (emitters)
13 RS485−A
14 RS485−B
15 Ground

Female 1/4" VCR
Gland and Nut

.50

[12.7]

6.71

[170.4]

1.06

[27.0]

2.13

[54.0]

X.XX = Dimensions in inches
[XX.X] = Dimensions in millimeters

Male 1/4" VCR
Gland and Nut

4X 8-32UNC-2B X .125 [3.2] DP

MOUNTING HOLES

[6.6]

[25.1]

.26

.99

5.13

[130.3]

3.15

[80.0]

1.10

[27.9]

.49

[12.4]

.51

[13/1]

Figure 2-1: M452A High Purity Ozone Sensor

Weight: 2.8 lbs. (1.27 kg)
Surface Finish:

Fittings:

M452 - 32  inch Ra
M452A – 10  inch Ra
M452 – ¼” Gyrolok
M452A – ¼” VCR

Wetted Materials: 316L Stainless Steel, Sapphire, Virgin

PTFE

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

2.2 Performance Specifications

Accuracy:
Repeatability:
Response Time: 2 sec. To 95%
Zero Drift: 1% Full Scale/month (non –cumulative)

1% of Full Scale.
1% of Full Scale

2.3 Operating Limits

Measurement Range: 5, 10, 15, 20% w/w
25, 50, 100, 200, 400 g/Nm3
Proof pressure: 115 psia
Flow: 0.1-5.0 LPM (See Figure 2-2)
Temperature range:
Warm-Up Period: 15 minutes

5 to 45 C

2.4 Electrical Specifications

Power Input:
Analog Output: 0-5V Full Scale
Zero Cal: Contact Closure Input
Digital Outputs: Sensor OK, Invalid Reading, Lamp Low,

Serial Data Interface: RS232 or RS485, Half-Duplex, 9600

+15 volts 1.0 volt (1.0A maximum)

Cell Dirty

Baud

2.5 Calibration Reference

Span Calibration: Traceable to Buffered KI laboratory

calibration
Standard
Temperature and
Pressure (g/Nm3
only):

0C and 760 mmHg

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

2.6 Pressure Drop

Figure 2-2 below shows the approximate pressure drop from the inlet
fitting to the outlet fitting as a function of volumetric flow rate.

Pressure Drop vs. Flow

1.000
y = 0.0008x2 + 0.0048x

0.800

0.600

P (psi)



0.400

0.200

0.000

0 5 10 15 20 25

Flow (LPM)

Figure 2-2: Pressure Drop vs. Flow (High Purity Version)

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

2.7 Options

The M452 is available with the following options:

2.7.1 AC Power Adapter

This option consists of a Universal Input (100-240 VAC, 50-60Hz) Power
Adapter with a standard IEC320 modular AC receptacle. A North
American standard 3 prong power cord is also provided.

2.7.2 Ozone Destructor (1/4” Tube Fittings)

This option consists of an external catalytic Ozone Destructor for
connecting to the gas outlet of the M452. The Ozone Destructor is
provided with ¼” compression tube fittings. When the Ozone Descructor
is used in conjunction with the M452, the gas flow rate must be limited to
a maximum of 1.0 L/min.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E





C

3 Theory of Operation

The detection of ozone molecules is based on absorption of 254 nm UV
light due to an internal electronic resonance of the O
Model 452 uses a mercury lamp constructed so that a large majority of the
light emitted is at the 254 nm wavelength. Light from the lamp shines
through an absorption cell through which the sample gas being measured is
passed. The ratio of the intensity of light passing through the gas to a
reference measurement, which does not pass through the gas, forms the
ratio I/I
concentration.

The Beer-Lambert equation, shown below, calculates the concentration of
ozone from the ratio of light intensities.

. This ratio forms the basis for the calculation of the ozone

o

molecule. The

3



273





o



C

O

3

Where:

I = Intensity of light passed through the sample
I

o

l

O

3

T
P

As can be seen the concentration of ozone depends on more than the
intensity ratio. Temperature and pressure influence the density of the
sample. The density changes the number of ozone molecules in the
absorption cell, which impacts the amount of light, removed from the light
beam. These effects are addressed by directly measuring temperature and
pressure and including their actual values in the calculation. The
absorption coefficient is a number that reflects the inherent ability of ozone
to absorb 254 nm light. Lastly, the absorption path length determines how
many molecules are present in the column of gas in the absorption cell.

1

 ln



l



= Intensity of light through sample free of ozone
= Absorption coefficient
= Path length
= Concentration of ozone

= Sample temperature in degrees Kelvin
= Pressure in pounds per square inch (absolute)

psi

695.14







o

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

The intensity of light is converted into a voltage by the detector/preamp
module. The voltage is converted into a number by a voltage-to-frequency
(V/F) converter capable of 80,000 count resolution. The digitized signal,
along with the other variables, is used by the CPU to compute the
concentration of ozone using the above formula.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4 Installation

4.1 Unpacking

Upon receiving the M452 please verify that no apparent shipping damage
has occurred. If damage has occurred please advise shipper first, then
Teledyne API.

4.2 Mechanical Installation

Mount the M452 to a stable platform using four #8-32UNC screws. See
Figure 2-1 for mounting hole dimensions.

NOTE

If the mounting platform is non-conductive or

note connected to earth ground, then a separate

connection to earth ground should be made using

one of the mounting screws. Failure to provide a

proper earth ground connection may make the

M452 susceptible to electrical interference from

external sources.

4.3 Electrical Connections

Electrical connections are made to the M452 using the 15 pin D-Sub
connector on the top of the device. Figure 4-1 shows the pin-out of the 15­pin connector and typical connections.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

Status Display

or

PLC

Digital Out #2
Digital Out #3
Digital Out #4

Digital Out Common
RS485-A
RS485-B
Power Common

Ozone Concentration

Meter

(0-5 VDC)

or Data Acqusition Device

-+

Analog Out ­Analog Out +
Power Common
+15 Volt Supply
+15 Volt Supply
Digital In #1
Digital In #2
Digital Out #1

Power Supply

+15V

Common

Zero Cal = Closed

Figure 4-1: Electrical Connections

4.3.1 Power Supply

The M452 requires a +15 VDC power source capable of supplying 1.0 A.
DC power can be connected through the male DB-15 connector or through
the coaxial power jack. The coaxial power jack is configured so that the
ground connection is on the outside (shield) and the +15V connection is on
the center pin.

If power is to be supplied through the DB-15 connector, the positive
terminal of the power supply should be connected to pins 4 and 5 on the
15-pin connector and the common terminal should be connected to pins 3
and 15.

If the optional AC Power Adapter is used to provide power, it should be
connected to the coaxial power connector adjacent to the DB-15 connector
on the top of the M452. Use only the approved AC Power Adapter
provided by Teledyne API.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4.3.2 Analog Output

The analog output is a 0-5 volt signal representing the ozone concentration
measured by the sensor. The output is scaled to the concentration range
that the sensor has been set to measure. Check the serial number label on
the M452 to determine the concentration range.

For best performance, the analog output should be connected to a
voltmeter or A/D converter with a differential input and a minimum input
impedance of 2K.

4.3.3 Zero Calibration Input

The zero calibration input is located on Digital Input #1. To zero the
M452, Digital Input #1 should be connected to the power common for at
least 1 second. This can be accomplished using a Normally Open switch or
relay.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4.3.4 Status Outputs

The M452 has four digital status outputs for indicating error status and
when operational parameters have moved out of normal limits. These
outputs are in the form of opto-isolated open-collector transistors. They
can be used to drive status LED’s on a display panel or interface to a
digital device such as a Programmable Logic Controller (PLC).

Figure 4-2 below shows the most common way of connecting the digital
outputs to an external device such as PLC. Note: Most devices, such as
PLC’s, have internal provision for limiting the current that the input will
draw from an external device. When connecting to a unit that does not
have this feature, external dropping resistors must be used to limit the
current through the transistor output to 50mA or less.

See Section 1 for details on using the Status Outputs for diagnosing sensor
and system-level malfunctions.

Opto-Isolator

M452

Digital Output #1-4 (Collector)

Digital Output Common (Emmiter)

Ground Provided
by PLC

Figure 4-2: Digital Output Connections

4-4

Programmable Logic
Controller or other device

+5V

Digital
Input

Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4.3.5 RS232/485 Interface

The M452 features a bi-directional digital serial interface that can be used
for sensor control and data acquisition. Please contact Teledyne API for
documentation on the use of the RS232/485 interface.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4.4 Gas Connections

Gas connections to the M452 are made using ¼” compression tube fittings
(M452) or ¼” VCR face seal fittings (M452A.) The ¼” compression
fittings can be used with ¼” O.D. Stainless Steel or Teflon tubing. The
M452 is not sensitive to flow direction; it does not matter which of the two
fittings is used as the gas inlet.

To avoid contamination of the optical cell in the M452, ensure that all
tubing upstream of the M452 is properly cleaned and purged before the
M452 is installed.

In order to achieve an acceptable response time and to avoid sample
degradation, the system should be set up so that a minimum flow rate of

0.1 LPM is established through the M452. If long tubing runs are used
between the measurement point and the M452, then higher flow rates
should be used to avoid sample degredation. Appropriate tests should be
conducted to determine minimum flow requirements.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

4.5 Start-Up and Calibration Procedure

1. Verify that the proper electrical connections have been made (See

Section 4.3) and apply power to the M452. Allow the M452 to warm
up for at least 15 minutes.

2. Purge the M452 with zero gas (usually oxygen) at a minimum flow

rate of 0.1 LPM for at least 2 minutes.

3. Check that the Status Outputs (See Section 4.3.4) are in their normal

states and no errors are indicated.

4. Close the zero calibration input (See Section 4.3.3) for a minimum of

1 second to perform the automatic zero calibration.

5. Re-check the Status Outputs to ensure that no errors are indicated.

6. Check the voltage on the analog output (See Section 4.3.2) and verify

that it reads 0.000  0.010 volts.

7. The M452 is now ready for operation.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

5 Sensor and System

Troubleshooting

This chapter gives guidelines for diagnosing system and sensor
malfunctions using the four digital Status Outputs provided by the M452.
All troubleshooting should be done after the M452 has been turned on and
allowed to warm up for at least 15 minutes.

5.1 Status LED’s

On the top of the M452 are five status LED’s.

The Status LED labeled ‘CPU STATUS’ is used to verify the status of the
CPU inside the M452. This LED should blink on and off continuously
while the sensor is on. If this LED stops blinking while power is applied
to the sensor, a CPU failure is indicated.

The other four Status LED’s on the M452 exactly mirror the four Status
Outputs described in the following sections.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

5.2 Status Outputs

Table 5-1 below describes the function of the status outputs. More details
as to the meaning of the status outputs are described in the following
sections.

Table 5-1: Status Outputs

Output # Name On State Off state

1 Sensor

O.K.

Normal State Reference or

Measure > 4995mV;
Reference <
1000mV

2 Invalid

Reading

3 Lamp

Low

4 Cell Dirty Measure/Reference

Pressure > 45 psia,
Negative Ozone
Concentration

Reference
Detector<600mV

ratio < 0.5 (zero
gas)

Normal State

Normal State

Normal State

5.3 Sensor O.K.

The normal state for the Sensor O.K. output in ON. During the warm-up
period on start-up this output will stay off until the UV lamp reaches a
minimum intensity. If this output remains off after the 15 minute warm-up
period, or goes off during normal operation, then the M452 is in need of
servicing.

If the Sensor O.K. output turns off AND the Lamp Low output is on, this
indicates that the lamp intensity has below the minimum level required for
proper operation.

If the Sensor O.K. output turns off and the Lamp Low output is also off,
then one of the analog voltages in the sensor has exceeded the range of the
internal A/D converter. Adjustment by qualified service personnel is
required.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

5.4 Invalid Reading

The normal state for the Invalid Reading output is OFF. If this output
turns on, this indicates that the M452 is still operational, but a system fault
or calibration fault exists that may make the current ozone reading invalid.

The Invalid Reading output is turned on for any of the following
conditions:

1. When the measured pressure in the M452 exceeds 45 psia.

2. When the measured concentration has exceeded the full-scale

concentration range of the sensor. Check the serial number tag for the
full-scale concentration range.

3. The sensor is indicating an excessive negative reading.

5.5 Lamp Low

The normal state for the Lamp Low output is OFF. If this output turns on,
this indicates that the UV lamp intensity as measured by the reference
detector has dropped below 600mV.

If the Lamp Low output turns ON and the Sensor O.K. output is ON, this
indicates that the lamp intensity is still adequate for measurement, but
adjustment should be made when possible.

If the Lamp Low output turns ON and the Sensor O.K. output is OFF, this
indicates a failure condition and accurate measurement is no longer
possible.

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Teledyne API M452 Ozone Sensor Instruction Manual, 02852, Rev. E

5.6 Cell Dirty

The normal state for the Cell Dirty output is OFF. If this output turns on,
then the ratio of the measure detector to the reference detector (at zero) is
< 0.5. This value is calculated when the zero calibration is performed.

When this output is on, it indicates a loss of optical transmission through
the windows in the absorption cell or a calibration fault.

5.7 Status Output Summary Table

Table 5-2 below is a logic truth table summarizing the recommended
actions based on the states of the four status outputs. A ‘1’ indicates the
output is ON, a ‘0’ indicates the output is OFF, and ‘X’ indicates the
output is in either state.

Table 5-2: Status Output Truth Table

Sensor

OK

1 0 0 0

0 X X X Service required

1 1 X X

1 X 1 X

1 X X 1

Invalid

Reading

Lamp

Low

Cell

Dirty

Actions

Normal operation, no
action required

Check Pressure > 45 psia
Verify that concentration
has not exceeded full scale
range of sensor.
Calibrate at Zero.

Lamp adjustment useful,
though not required

Calibrate at zero
Clean Cell

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