SEC Signature DIR Manual

SEC Signature DIR Process Monitor
Instruction and Operation Manual
Sensor Electronics Corporation
12730 Creek View Avenue
Savage, Minnesota 55378 USA
[phone] Fax [phone]
email [email protected] or www.sensorelectronics.com
Part Number 71-3001 Version 011008

Sensor Electronics Corporation
Sensor Electronics Corporation (SEC) is an innovative manufacturer of fixed system gas detection equipment, for
combustible gases, oxygen and toxic gases.
Commitment
Our quality and service are uncompromising. We back each of our products with a two-year warranty on all materials and
workmanship. We offer technical support, user training and on-site service and maintenance of equipment to meet the
needs of our customers.
Gas Detection Service
Individually designed maintenance packages are available for specific customer needs. Service begins with verification of
the system installation that includes an initial system check and calibration. We then offer customer training programs (on-
site and at factory) to insure that technical personnel fully understand operation and maintenance procedures. When on-
the-spot assistance is required, service representatives are available to handle any questions or problems immediately.
WARRANTY
SENSOR ELECTRONICS CORPORATION (SEC) WARRANTS PRODUCTS MANUFACTURED BY SEC TO BE FREE
FROM DEFECTS IN WORKMANSHIP AND MATERIALS FOR A PERIOD OF TWO (2) YEARS FROM DATE OF
SHIPMENT FROM THE FACTORY. ANY PARTS RETURNED FREIGHT PRE-PAID TO THE FACTORY AND FOUND
DEFECTIVE WITHIN THE WARRANTY WOULD BE REPAIRED OR REPLACED, AT SEC'S OPTION. SEC WILL
RETURN REPAIRED OR REPLACED EQUIPMENT PRE-PAID LOWEST COST FREIGHT. THIS WARRANTY DOES
NOT APPLY TO ITEMS, WHICH BY THEIR NATURE ARE SUBJECT TO DETERIORATION OR CONSUMPTION IN
NORMAL SERVICE. SUCH ITEMS MAY INCLUDE:
CHEMICAL SENSOR ELEMENTS
FUSES AND BATTERIES.
WARRANTY IS VOIDED BY ABUSE INCLUDING ROUGH HANDLING, MECHANICAL DAMAGE, ALTERATION OR
REPAIR. THIS WARRANTY COVERS THE FULL EXTENT OF SEC LIABILITY AND SEC IS NOT RESPONSIBLE FOR
REMOVAL, REPLACEMENT COSTS, LOCAL REPAIR COSTS, TRANSPORTATION COSTS OR CONTINGENT
EXPENSES INCURRED WITHOUT PRIOR WRITTEN APPROVAL. SENSOR ELECTRONICS CORPORATION'S
OBLIGATION UNDER THIS WARRANTY SHALL BE LIMITED TO REPAIR OR REPLACEMENT OF ANY PRODUCT
THAT HAS BEEN RETURNED TO SENSOR ELECTRONICS CORPORATION FOR WARRANTY CONSIDERATION.
THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY AND ALL OTHER WARRANTIES EXPRESSED OR IMPLIED,
AND ALL OTHER OBLIGATIONS OR LIABILITIES ON THE PART OF SENSOR ELECTRONICS CORPORATION
INCLUDING BUT NOT LIMITED TO, THE FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SENSOR
ELECTRONICS CORPORATION BE LIABLE FOR DIRECT, INCIDENTAL, OR CONSEQUENTIAL LOSS OR
DAMAGE OF ANY KIND CONNECTED WITH THE USE OF IT'S PRODUCTS OR FAILURE TO FUNCTION OR
OPERATE PROPERLY.

Table of Contents
I. SPECIFICATIONS
II. GENERAL DESCRIPTION
Features
Theory of Operation
III. INSTALLATION
Mechanical
Electrical
IV. CALIBRATION / OPERATION
Zeroing
Warm Up
Normal
Spanning
Calibration Certification
V. PARTS LIST
VI. DRAWING SECTION
Figure 1 Dimensions/Wiring
Figure 2 Mounting
Figure 3 PC Link Wiring
Figure 4 Sensor Separation Kit

I. SPECIFICATIONS
Model: SEC Signature DIR Part Number: DIR011021000000
Measuring Range: EtO Channel:0-2000 milligrams/liter (maximum)
Factory calibrated to 0-1000 mg/l EtO
H2O Channel: 0-500 milligrams/liter (maximum)
Factory calibrated to 0-300mg/l H2O
Detection Method: Diffusion
Construction: Housing is anodized aluminum with sapphire optical windows.
Rating:CSA: Class 1, Division 1, Groups BCD
Accuracy: +/- 5% measured value or +/- 3% full scale (whichever greater)
Repeatability: +/- 3%
Operating Temperature Rating: +0C to +75C (maximum)
+32F to +167F (maximum)
Operating Voltage: 24 VDC. Operating range 18 to 32 VDC measured at the detector head.
Outputs (analog): 4-20 mA (Source type), max. 1000 Ohm load at 24 VDC supply voltage.
Output (digital): Interactive PC Link
Power Consumption at 24 VDC: 35 watts (Max)
Current Draw at 24 VDC: 1A (average)
Mechanical connection to sterilizer: ¾” NPT male
Electrical connection: ¾” NPT male
Weight: 30 ounces
Wire Connections: Red wire (+ 24 VDC)
Black wire (D.C. common)
Blue wire (4-20 output EtO)
Yellow Wire (4-20mA output H2O)
White wire (Calibration / digital interface)
Brown wire (Pressure Input 4-20mA)

II. GENERAL DESCRIPTION
The SEC Signature DIR Process monitor is a microprocessor based intelligent device that continuously and
simultaneously monitors levels of EtO and H2O in sterilization chambers.
The SEC Signature DIR Process monitor is a stand-alone device providing a dedicated 4-20 mA signal
corresponding to actual concentrations of ethylene oxide and a dedicated 4-20mA signal corresponding to the
actual concentration of H2O.
Features
Programmable Heater operates in Relative or Closed Loop Mode.
Continuous self-test automatically indicates a fault, with fail to safe operation.
A multi-layered filtering system protects optics from dirt and water ingress.
Straight optical path eliminates the need for mirrors, reflective surfaces or beam splitters thereby increasing
the stability and reducing the maintenance of the device.
Discourages condensation interference by internally heating optical chamber.
Standard 4 to 20 mA outputs (current sources).
Explosion proof housing designed for duty in harsh environments.
Smart Calibration AutoACcircuit.
Theory of Operation
The SEC Signature DIR Process monitor uses infrared absorption technology for detecting target gas
concentrations. Gases absorb infrared light only at certain wavelengths. The concentration of a gas can be
measured by the difference of two channels (wavelengths), a reference and a measurement channel. The SEC
Signature DIR Process monitor uses an infrared light source at one end and a dual channel receiver at the
opposite end. The dual channel receiver measures the intensity of two specific wavelengths, one at an
absorption wavelength and another outside of the absorption wavelength. The gas concentration is determined
by a comparison of these two values.
The multi channel receivers incorporate single wafer double filter technology with internal optical barriers. The
elements are perfectly matched resulting in overall stability and superior performance throughout the entire
temperature range. By using this multi channel receiver there is no need to use any special lenses or beam
splitters to achieve the dual measurement bands.
The SEC Signature DIR Process monitor utilizes a unique Automatic Analog Control circuit, the AutoACcircuit
(Patent Pending). The AutoACcontinuously makes adjustments to null out effects from temperature,
component drift, dirty optics, interferents and aging. These adjustments are made according to algorithms
derived from infrared gas absorption theory. The AutoACcircuit is continuously checking all unit operating
parameters. If any parameter goes out of tolerance, the AutoACcircuit sets a fault code appropriate to the
problem. The AutoACcircuit ensures that once the unit is spanned, it will remain accurate as long as the zero
is accurate. Simply calibrate (span one time) the unit with a specific amount of gas and the device will
repeatable track the gas concentrations in the chamber throughout the entire load cycle. The only ongoing
calibration that is necessary is an occasional zero.
The optical absorption efficiency of water vapor is a function of the chamber pressure. Higher chamber
pressures cause more absorption resulting in higher signal levels.
The H2O channel is designed to be accurate with pressure rise due to the vapor pressure of the H2O in the
chamber.
Pressure rise due to N2 EtO injections will cause higher H2O readings. Therefore, the H2O signal will be
accurate as long as the chamber contains only water vapor.

If accurate readings are required throughout the entire cycle, pressure compensation will be necessary.
Pressure compensation is achieved by adding the pressure compensation option and using a dedicated
absolute pressure sensor mounted close to the sensor. The 4-20mA output from the pressure sensor is
connected to the sensor’s pressure input wire.
III. INSTALLATION
Mechanical
The SEC Signature DIR Process monitor has a ¾” male NPT threaded connector for installing the device on the
sterilizer. Ideally the device can be installed on the recirculation line (see Figure 4). The device is vacuum
tested at the factory to 1 inches of mercury absolute and pressure tested to 40 psi.
Electrical
The SEC Signature DIR Process monitor has a ¾” male NPT threaded connector (with 4 wires) for mounting the
detector to a junction box. SEC can provide a junction box for this purpose with terminals (see Figure 5).
A user-supplied junction box can also be used, providing it has the appropriate sized NPT conduit entries. This
junction box must be suitable for use in the application and location in which it is being installed.
Wiring connections
Red wire: 18 to 32 VDC
Black wire: DC negative (common)
Blue wire: 4 to 20 mA output EtO
Yellow wire: 4 to 20 mA output H2O
White wire: Smart Calibration Wire (data wire)
Brown wire: Pressure Input (4-20mA)
Refer to Figures 2 and 3 for general wiring details.
Insulator
The SEC DIR Signature internal temperature should be at least 6º C warmer than the process temperature.
Temperature rise can be adjusted by adjusting heater level. The internal temperature of the Signature DIR can
be adjusted and monitored using the SEC IR PC LINK software package. If more temperature rise is needed
with heater at full power, it may be necessary to insulate sensor.
IV. OPERATION
Warm-up
When power is applied to the detector, it enters a one (1) minute warm-up mode in which time it performs
diagnostic checks and allows the sensor to stabilize before beginning normal operation. The current output
during this period is 0.8 milliamperes. At the end of the warm-up period with no faults present, the detector
automatically enters the normal operating mode. If a fault is present after warm-up, the detector current output
will indicate the fault (see chart above).
Normal
In the normal operating mode, the 4 to 20 mA signal levels correspond to the detected gas concentrations. The
device continuously performs self diagnostics, checks for calibration requests and displays operating status (see
table).
Calibration
Calibration operations and Parameter download are accomplished via the Sensor’s white wire.
White wire is connected to Data Translator (SEC IR PC Link P/N 1420636)
Data Translator is connected to PC via serial port. Operating from USB port requires a USB to serial converter.
Commands are issued from PC (Software Package Supplied by SEC)
The software is compatible with most versions of MicrosoftWindows
Note: For best accuracy, the unit should be powered up for at least 1 hour before any calibration operation.

Zeroing
EtO (Channel 0)
Zeroing should be performed:
When unit is installed on chamber
If Sensor doesn’t return to zero between cycles
If Sensor shows abnormally high or low concentration readings during EtO exposure.
Annually (more often if the load material is dusty or oily)
Procedure:
After chamber evacuation, water injection and dwell:
Move cursor to “Zero EtO Channel” using “Up/Down” arrows
<enter>
Zero Channel 0 ? (Y/N)
<Y><enter> will initiate Zero Operation
The EtO output goes to 2.2mA while Zeroing.
A successful Zero will result in 4.0mA
An unsuccessful Zero will result in a 4-20mA fault level. (<4mA) See Status table.
H2O (Channel 1)
Zeroing should be performed:
When unit is installed on chamber.
If sensor shows abnormally high or low concentration readings during H2O exposure.
Annually (more often if the load material is dusty or oily)
Procedure:
It is very difficult to remove water from the chamber. Even after several N2 washes and evacuations, enough
water can remain in the chamber to skew the zero. The best way to ensure an accurate zero is to apply dry N2
directly to the sensor either in the chamber or removed from the chamber.
Procedure:
Move cursor to “Zero H2O Channel” using “Up/Down” arrows
<enter>
Zero Channel 1? (Y/N)
<Y><enter> will initiate Zero Operation
The H2O output goes to 2.2mA while Zeroing.
A successful Zero will result in 4.0mA
An unsuccessful Zero will result in a 4-20mA fault level. (<4mA) See Status table.
Note: For best accuracy, the unit should be powered up for at least 1 hour before any calibration operation.
Note: When calibrating with the sensor removed from chamber, best accuracy is obtained by calibrating with the
sensor in the same physical orientation as when installed on chamber.
Current Output and Corresponding Status Table
The 4 to 20 mA outputs are non-isolated current sources.
Current Output Status .
4-20 mA Normal measuring mode
0.0 mA Unit Fault
0.2 mA Reference channel fault
0.4 mA Analytical channel fault
0.8 mA Unit warm up
1.0 mA Optics fault
1.2 mA Zero drift fault
1.6 mA Calibration fault
2.0 mA Unit spanning
2.2 mA Unit zeroing
4.0 mA Zero gas level
20 mA Full scale

Spanning
Spanning is only required to establish measurement range. Spanning teaches the unit what 50% of full scale
looks like (25% for H2O).
The unit is designed to be spanned at the typical empty chamber operating concentration. The fact that the span
value becomes 50%(25%) of full scale gives the unit over-range capability. This is important since certain loads
will cause the EtO concentration (in the headspace) to spike much higher than the theoretical concentration right
after injection. Over-range capability allows the unit to track concentrations through the spikes.
The span will only be as accurate as the Zero point. Spanning should always be proceeded with Zeroing.
(Example) When the EtO channel is spanned at 520 mg/l, full scale range is 0 to 1040 mg/l.
When the H2O channel is spanned at 75 mg/l, full scale range is 0 to 300 mg/l.
EtO(Channel 0)
The EtO channel is factory coarse spanned with ethylene span gas to a range of 0-1000 mg/l EtO.
Spanning should be performed:
If abnormally high or low EtO readings are observed during EtO exposure and re-zeroing didn’t
resolve the problem.
If the unit needs to be ranged for a different full scale concentration.
Procedure:
Perform Zero Operation.
Introduce desired EtO concentration into chamber and let equilibrate.
Move cursor to “Span EtO Channel” using “Up/Down” arrows
<enter>
Span Channel 0 ? (Y/N)
<Y><enter> will initiate Span Operation
The EtO output goes to 2.0mA while Spanning.
A successful Span will result in 12mA
An unsuccessful Span will result in a 4-20mA fault level. (<4mA) See Status table.
H2O(Channel 1)
The H2O channel is factory spanned with 20.5 % volume CO2 (balance N2) span gas to a range of 0-300 mg/l
H2O.
Spanning should be performed:
If abnormally high or low H2O readings are observed during H2O exposure and re-zeroing didn’t
resolve the problem. (Be aware of pressure response that could be skewing your readings)
If the unit needs to be ranged for a different full scale concentration.
Procedure:
Perform Zero Operation.
Introduce desired H2O concentration into chamber and let equilibrate.
Move cursor to “Span H2O Channel” using “Up/Down” arrows
<enter>
Span Channel 0 ? (Y/N)
<Y><enter> will initiate Span Operation
The H2O output goes to 2.0mA while Spanning.
A successful Span will result in 8 mA
An unsuccessful Span will result in a 4-20mA fault level. (<4mA) See Status table.
Note: For best accuracy, the unit should be powered up for at least 1 hour before any calibration operation.

Heater Adjustment
Relative Mode (Recommended)
In the Relative Mode, a constant power level is applied to the heaters. This will give the best accuracy over
process temperature variations. There are 10 fixed power levels; 0=heaters off, 10=Full Power.
The sensor temperature is a function of process temperature, mounting surface temperature, and ambient
temperature. Therefore, an empirical method is the best way to set the heater level.
Procedure:
To adjust heater, select “Heater Level”
The heater mode will be displayed (Relative)
Followed by the current Heater Level
Followed by “Change Power Level? (Y/N)”
<Y><enter>
“New Heater Level: “
Enter Heater Level and <return>
Closed Loop Mode
In the Closed Loop Mode, a target temperature set by user and the heater level is automatically adjusted to
keep the sensor temperature at the target temperature.
Procedure:
To adjust target temperature, select “Heater Level”
The heater mode will be displayed (Closed Loop)
Followed by the current Target Temp
Followed by “Change Target Temp? (Y/N)”
<Y><enter>
“New Target Temp: “
Enter Target Temp and <return>

Calibration Certification
Document: 7305 Rev. 1.001
Customer:
Sales Order:
Ship Date:
SEC
Signature
DIR Serial #
Channel
Cal Date
Cal Gas Value
Span Hex Value
Check Sum
(Linearization)
Firmware Rev
Channel 0
EtO
70% Volume Ethylene
+/-2% NIST Traceable
Channel 1
H2O
20.5% Volume CO2
+/-2% NIST Traceable
Calibration Procedure: 7304
Test Procedure: 7302
TEST PERSON SIGNATURE PRINT NAME DATE
__________________________ _______________________ ____________
70%V/V Ethylene generates a unit response approximately equivalent to 500 mg/l ethylene oxide. This results in a
range of 0-1000mg/l.
20.5%V/V CO2 generates a unit response approximately equivalent to 75 mg/l water vapor. This results in a range of
0-300mg/l.
Best accuracy requires the unit to be zeroed and spanned in-chamber at operating temperature and humidity, using
typical concentrations of EtO and H2O for spanning.
Example of Calibration Certification
Each SEC Signature is shipped with a completed Calibration Certification.

V. PARTS LIST
Part Number Description
DIR011021000000 SEC Signature DIR Process monitor
142-1750 SEC DIR PC Link Kit
190-10001 SEC 2001 Explosion proof junction box
142-0852 Replacement Screen
142-0701 Replacement Filter
VI. DRAWING SECTION
Figure # Title
Figure 1 Dimensions/Wiring
Figure 2 Mounting
Figure 3 PC Link Wiring
Figure 4 Sensor Separation Kit

Figure 1

Figure 2

Chart Recorder
PLC, DAS, DCS, DVM
(Any control or monitoring system that accepts a 4-20 mA or 0-5 VDC signal)
Figure 3
SEC IR PC LINK
AC
Power
EtO/H20
MONITOR

Figure 4