Wet Labs ECO FL User manual

ECO FL User’s Guide (FL) Revision AN 4 June 2012
ECO Fluorometer
ECO FL
User’s Guide
The user’s guide is an evolving document. If you find sections that are unclear, or missing
information, please let us know. Please check our website periodically for updates.
WET Labs, Inc.
P.O. Box 518
Philomath, OR 97370
541-929-5650
fax: [phone]
www.wetlabs.com

ECO FL User’s Guide (FL) Revision AN 4 June 2012
ECO Sensor Warranty
This unit is guaranteed against defects in materials and workmanship for one year from the
original date of purchase. Warranty is void if the factory determines the unit was subjected to
abuse or neglect beyond the normal wear and tear of field deployment, or in the event the
pressure housing has been opened by the customer.
To return the instrument, contact WET Labs for a Return Merchandise Authorization (RMA) and
ship in the original container. WET Labs is not responsible for damage to instruments during the
return shipment to the factory. WET Labs will supply all replacement parts and labor and pay for
return via 3rd day air shipping in honoring this warranty.
Return Policy for Instruments with
Anti-fouling Treatment
WET Labs cannot accept instruments for servicing or repair that are treated with anti-fouling
compound(s). This includes but is not limited to tri-butyl tin (TBT), marine anti-fouling paint,
ablative coatings, etc.
Please ensure any anti-fouling treatment has been removed prior to returning instruments to
WET Labs for service or repair.
Shipping Requirements
1. Please retain the original ruggedized shipping case. It meets stringent shipping and
insurance requirements, and protects your meter.
2. Service and repair work cannot be guaranteed unless the meter is shipped in its original
case.
3. Clearly mark the RMA number on the outside of your case and on all packing lists.
4. Return instruments using 3rd day air shipping or better: do not ship via ground.
Electrical equipment marked with this symbol may not be disposed
of in European public disposal systems. In conformity with EU
Directive 2002/96/EC (as amended by 2003/108/EC), European
users of electrical equipment must return old or end-of-life
equipment to the manufacturer for disposal at no charge to the user.

ii ECO FL User’s Guide (FL) Revision AN 4 June 2012

ECO FL User’s Guide (FL) Revision AN 4 June 2012 i
Table of Contents
1. Overview ........................................................................................................................... 1
1.1 Specifications ...................................................................................................................... 1
1.2 Connectors .......................................................................................................................... 2
1.3 Delivered Items .................................................................................................................... 3
1.4 Optional Equipment ............................................................................................................. 3
2. Theory of Operation ......................................................................................................... 6
3. Instrument Operation ....................................................................................................... 7
3.1 Initial Checkout .................................................................................................................... 7
3.2 Operating the Sensor for Data Output .................................................................................. 7
3.3 Bio-wiper™ Operation .......................................................................................................... 8
3.4 Deployment ......................................................................................................................... 9
3.5 Upkeep and Maintenance .................................................................................................... 9
4. FLB and FLSB: Using Internal Batteries....................................................................... 12
4.1 Removing End Flange and Batteries .................................................................................. 12
4.2 Replacing End Flange and Batteries .................................................................................. 13
4.3 Checking Vent Plug ........................................................................................................... 14
5. Data Analysis ................................................................................................................. 15
5.1 Scale Factor ...................................................................................................................... 15
5.2 Analog Response............................................................................................................... 15
5.3 Digital Response ................................................................................................................ 16
6. Characterization and Testing ........................................................................................ 17
7. Terminal Communications ............................................................................................ 18
7.1 Interface Specifications ...................................................................................................... 18
7.2 Command List.................................................................................................................... 18
8. Device and Output Files ................................................................................................ 19
8.1 Plot Header........................................................................................................................ 19
8.2 Column Count Specification ............................................................................................... 19
8.3 Column Description ............................................................................................................ 19
8.4 Sample Device File ............................................................................................................ 20
8.5 Sample Output Files .......................................................................................................... 21
Appendix A: Mounting Bracket Drawing .......................................................................... 22
WET Labs WEEE Policy ........................................................................................................ 23
WEEE Return Process ................................................................................................................. 23

ECO FL User’s Guide (FL) Revision AN 4 June 2012 1
1. Overview
WET Labs offers a range of the Environmental Characterization Optics (ECO) series
fluorometers for the following measurements: chlorophyll, Colored Dissolved Organic Matter,
uranine, rhodamine, and phycocyanin and phycoerythrin. This section includes meter and
connector specifications, delivered items and descriptions of features, including internal batteries
and Bio-wiper™.
1.1 Specifications
FL(RT)—Provides analog or RS-232 serial output with 16,000-count range. This unit provides
continuous operation when powered.
FL(RT)D—Provides the capabilities of the FL(RT) with 6,000-meter depth rating.
FL—Provides the capabilities of the FL(RT) with periodic sampling.
FLS—Provides the capabilities of the FL with an integrated anti-fouling bio-wiper™.
FLB—Provides the capabilities of the FL with internal batteries for autonomous operation.
FLSB—Provides the capabilities of the FLS with internal batteries for autonomous operation.
FL(RT)
FL(RT)D
FL
FLS
FLB
FLSB
Mechanical
Diameter 6.3 cm
Length 12.7 cm 17.68 cm
12.7 cm 13.3 cm 27.4 cm 27.99 cm
Weight (in air) 0.4 kg 1.3 kg 0.4 kg 0.5 kg 0.96 kg
Weight (in water) 0.02 kg 0.75 kg 0.02 kg 0.08 kg 0.14 kg
Pressure housing acetal titanium Acetal copolymer
Environmental
Temperature range 0–30 deg C
Depth rating 600 m 6000 m 600 m 300 m
Optional pressure sensor No Yes
Optional thermistor No Yes
Electrical
Digital output resolution 14 bit
Analog output signal 0–5 V
Internal data logging No No Yes
Internal batteries No Yes
Connector MCBH6M
Input voltage 7–15 VDC
Current, typical 50 mA
Current, sleep -- 85 µA
Data memory -- 108,000 samples
Sample rate to 8 Hz
RS-232 output 19200 baud
Optional anti
-
fouling
Bio-wiper™ No Yes No Yes
Bio-wiper™ cycle -- 140 mA
-- 140 mA

2 ECO FL User’s Guide (FL) Revision AN 4 June 2012
Optical Specifications for Fluorescence Meters
Specifications given below are typical. Linearity for all is 99% R2. Other ranges are available on
request.
Parameter
EX/EM
Sensitivity
Range
Chlorophyll-a (Chl) 470/695 nm 0.02 µg/l 0–125 µg/l
Colored Dissolved Organic Matter (CDOM) 370/460 nm 0.09 ppb 0–500 pp
Uranine (UR) (fluorescein) 470/530 nm 0.05 ppb 0–400 ppb
Rhodamine (Rh) 540/570 nm 0.03 ppb 0–230 ppb
Phycocyanin (PC) 630/680 nm 0.03 ppb 0–230 ppb
Phycoerythrin (PE) 540/570 nm 0.03 ppb 0–230 ppb
1.2 Connectors
ECO-series digital fluorometers use a six-pin bulkhead connector. The pin functions for this
connector are shown below.
Pin
Function
1
Ground
2
RS
-
232 (RX)
3
Re
served
4
V in
5
RS
-
232 (TX)
6
Analog out
WARNING
If you are going to build or use a non-WET Labs-built cable, do not use the
wire from pin 3 or the ECO meter will be damaged.
Input power of 7–15 VDC is applied to pin 4. The power supply current returns through the
common ground pin. The input power signal has a bi-directional filter. This prevents external
power supply noise from entering into ECO FL, and also prevents internally generated noise
from coupling out on to the external power supply wire. Data is sent out the serial output pin.
1.2.1 ECO FLB, FLSB Connectors
ECO FLB and FLSB (units with internal batteries) have a second bulkhead connector that
comes with a jumper plug to supply power to the unit. The pin functions for this
connector are shown below.
Socket
Function
1 V in
2 N/C
3 Battery out

ECO FL User’s Guide (FL) Revision AN 4 June 2012 3
1.3 Delivered Items
The standard ECO delivery consists of the following:
 the instrument itself
 dummy plug with lock collar
 protective cover for optics
 this user’s guide
 ECOView user’s guide
 ECOView host program and device files (on CD)
 instrument-specific calibration sheet
 FL(RT), FL, FLS only: stainless steel mounting bracket and hardware (See Appendix A
for details)
 Internal battery units: six 9-V Lithium batteries (installed)
Spare Parts
 Fluorescent stick for bench testing
 Bio-wiper™ units: one 3/32-in. hex key for Bio-wiper™ removal
 Bio-wiper™ units: Three 4-40 x 3/8 in. 316 stainless steel screws for securing Bio-wiper™
Additional spare parts for internal battery units
 Two end flange O-rings (size 224) and two vent plug O-rings (size 010)
 Two jacking screws for connector flange removal
 One 3/32-in. hex key for jacking screws
 Blue-tipped power plug for autonomous operation
 Three pre-cut segments (7 inches) of 0.036-inch diameter monofilament for end flange
 Three pre-cut segments (0.25 inches) of 0.094-inch diameter white nylon bar stock
for replacing the white plastic dowel pin.
1.4 Optional Equipment
1.4.1 Test Cable
A test cable is optionally available with each unit. This cable includes:
1. An inline connector for providing power to the instrument from a user-supplied 9V
battery.
2. An auxiliary analog out connector.
3. A DB-9 serial interface connector.
4. A six-socket connector for providing power and signal to the instrument.
1.4.2 Copper Faceplate
ECO meters are optionally equipped with copper faceplates to improve the meter’s
resistance to biofouling. Refer to Section 3.5.1 for important details on maintenance and
cleaning.
1.4.3 Bio-wiper™ and Copper Faceplate
The FLNTUS and FLNTUSB are equipped with an integrated non-contact anti-fouling Bio-
wiper™ and copper faceplate for use in extended deployments. This wiper can be manually
controlled by a host controller package, or can perform autonomously as part of a pre-
programmed sampling sequence upon instrument power-up. The rate of closure and
opening is dependent upon both temperature and depth.

4 ECO FL User’s Guide (FL) Revision AN 4 June 2012
Refer to Section 3.5.1 for important details on the maintenance and cleaning of the Bio-
wiper™ and copper faceplate.
WARNING!
Do NOT rotate the Bio-wiper™ manually. This can damage the wiper motor and will
void the warranty.
1.4.4 Batteries
ECO units with internal batteries are supplied with six 9-volt Lithium batteries as their
power source. They can use either standard alkaline cells for a total capacity of
approximately 1000 mA-hrs, or for longer deployments, LiMnO2 cells to achieve more
than 2000 mA-hrs of operational capacity. Actual total usage time of the internal batteries
is a function of several parameters. These include nominal water temperature, sequence
timing, sample periods, and total deployment duration.
For even greater deployment capability contact WET Labs for information on external
battery packs.
1.4.5 External Thermistor
ECO meters are optionally equipped with an external thermistor. The thermistor is
calibrated at WET Labs and the calibration coefficients are supplied on the instrument’s
calibration sheets. Thermistor output is in counts and can be converted into engineering
units using the instrument’s device file and ECOView software or the raw data can be
converted in the user’s software (e.g. MATLAB or Excel) using the calibration equation:
Temperature (deg C) = (Output * Slope) + Intercept
1.4.6 Pressure Sensor
ECO meters are optionally equipped with a strain gauge pressure sensor. The pressure
sensor is calibrated at WET Labs and the calibration coefficients are supplied on the
instrument’s calibration sheets. Pressure sensor output is in counts and can be converted
into engineering units using the instruments device file and ECOView software or the
raw data can be converted in the user's software (e.g. MATLAB or Excel) using the
calibration equation:
Relative Pressure (dbar) = (Output * Slope) + Intercept
Please note that strain gauge pressure sensors are susceptible to atmospheric pressure
changes and should be “zeroed” on each deployment or profile. The calibration equation
for pressure above should be used first to get the relative pressure and the cast offset
should then be subtracted to get the absolute pressure:
Absolute Pressure (dbar) = Relative Pressure (dbar) - Relative Pressure at
Atmospheric/Water interface (dbar)
WARNING!
Do not exceed the pressure sensor’s depth rating (see calibration sheet).

ECO FL User’s Guide (FL) Revision AN 4 June 2012 5
Pressure Sensor Maintenance
A plastic fitting filled with silicone oil provides a buffer between the pressure
transducer and seawater. The transducer is both sensitive and delicate. Following the
procedures below will ensure the best results and longest life from your pressure
sensor.
Pressure is transmitted from the water to the stainless steel transducer diaphragm via a
plastic fitting filled with silicone oil. The inert silicone oil protects the pressure sensor
from corrosion, which would occur after long exposure to salt water. The fitting will
generally prevent the oil from escaping from the reservoir into the water. However,
you may occasionally wish to ensure that oil remains in the reservoir on top of the
transducer.
WARNING!
Never touch or push on the transducer.
1. Thoroughly clean the top of the instrument.
2. Completely remove the white nylon Swagelock fitting using a 9/16-in. wrench.
3. Check for obstructions in the tiny hole. Blow clear with compressed air or use a
small piece of wire.
4. Wipe clean the o-ring at the base of the Swagelock fitting.
5. Screw the Swagelock fitting into the end flange until finger tight.
6. Tighten it an additional 1/8 turn using a wrench only if necessary.
7. Wipe up any excess oil.

6 ECO FL User’s Guide (FL) Revision AN 4 June 2012
2. Theory of Operation
The Environmental Characterization Optics, or ECO miniature fluorometer allows the user to
measure relative chlorophyll, CDOM, uranine, phycocyanin, or phycoerythrin concentrations by
directly measuring the amount of fluorescence emission in a sample volume of water. The ECO
uses an LED to provide the excitation source. An interference filter is used to reject the small
amount of out-of-band light emitted by the LED. The light from the source enters the water
volume at an angle of approximately 55–60 degrees with respect to the end face of the unit.
Fluoresced light is received by a detector positioned where the acceptance angle forms a 140-
degree intersection with the source beam. An interference filter is used to discriminate against
the scattered excitation light.
Optical configuration of ECO fluorometer

ECO FL User’s Guide (FL) Revision AN 4 June 2012 7
3. Instrument Operation
Operating environment notice
ECO sensors are precision instruments. Data transfers should be performed away from harsh
environments such as strong electric fields or electrostatic discharge sources. If used in a such an
environment, there is a chance that the sensor may experience disturbances that will temporarily stop
data transfers. In that event, move the sensor to a location further from the electric field or ESD
source. Reset the sensor by momentarily turning its power supply off, then on.
Please note that certain aspects of instrument operation are configuration-dependent. These are
noted where applicable within the manual.
3.1 Initial Checkout
Supplied from the factory, ECOs are configured to begin continuously sampling upon power-
on. Electrical checkout of ECO is straightforward.
UV LED Safety Note—CDOM Fluorometers

UV LEDs emit intense UV light during operation.
 Do not look directly into a UV LED while it is in operation,
as it can be harmful to the eyes, even for brief periods.
 If it is necessary to view a UV LED, use suitable UV-
filtered glasses or goggles to avoid damage to the eyes.
 Keep UV LEDs and products containing them out of the
reach of children.
 Take appropriate precautions, including those above, with
pets or other living organisms that might suffer injury or
damage from exposure to UV emissions.
This label is affixed to all products
containing UV LEDs.
Connect the 6-socket connector on the optional test cable to the instrument to provide power to
the LEDs and electronics (see Section 1 for a diagram of the pin-outs of ECO FL). Connect the
battery leads on the test cable to the 9V battery supplied with the meter. Light should emanate
from the meter.
3.1.1 Analog Option
Connect a digital multimeter (DMM) to the auxiliary leg of the test cable: the center of the
RCA connector provides analog out signal and the outside provides ground. With the
sensor face clean and dry the instrument should read approximately 0.050–0.095 VDC. The
analog signal will saturate at 5 volts.
3.2 Operating the Sensor for Data Output
Note
ECO meters are sensitive to AC light. Before making measurement, turn AC lighting off.

8 ECO FL User’s Guide (FL) Revision AN 4 June 2012
1. Connect the 6-socket connector to the instrument to provide power to the LEDs and
electronics. Connect the DB-9 connector to a computer with the ECOView host program
installed on it.
WARNING!
Always use a regulated power supply to provide power to ECO sensors if not using the
9V battery provided with the test cable: power spikes may damage the meter.
2. Start ECOView. Select the appropriate COM Port and Device File. Supply power to the
meter, then click on the Start Data button. Output will appear in the Raw Data window.
Test the instrument’s signal using the fluorescent stick. ECO is sensitive to room lighting;
for best results, perform test in ambient light only (turn off AC lighting). Remove the
protective cover. Hold the fluorescent stick 1–4 cm above the optical paths in an orientation
that maximizes exposure of the stick. (Parallel with the beams, not intersecting them). The
signal will increase toward saturation (maximum value on characterization sheet). When
applying power to sensors with a Bio-wiper™, it will open and, depending on the settings,
operate until you select Stop Data in ECOView (or input !!!!! in a terminal program)
The Bio-wiper™ will close and the instrument will await the next command.
3. If the sensor completes the requested samples (this is common for meters set up in moored
applications), it will go into sleep mode, and the meter will not light when power is cycled.
To “wake” the meter, click Stop Data five times at the rate of two times a second
immediately upon supplying power. This interrupts the sensor, returning it to a “ready”
state, awaiting commands.
4. Check the settings for the ECO and change if necessary. ECOView factory settings for
continuous operation:
 Set Number of Samples = 0
 Set Number of Cycles = 0.
 Internal Memory=On
5. If the meter does not light after performing step 3, check the battery. Replace if necessary,
perform steps 2 and 3 to verify communication. If it still does not light, contact WET Labs.
Refer to the ECOView User’s Guide for details about using the software.
3.3 Bio-wiper™ Operation
The ECO-FLS and -FLSB are provided with an anti-fouling Bio-wiper™ and faceplate that
extend the possible deployment duration by retarding biological growth on the instrument’s
optical surface. The Bio-wiper™ covers the optical surface: 1) while the instrument is in
“sleep” mode; 2) when it has completed the number of samples requested; and 3) when the
user selects Stop Data in ECOView or types “!!!!!” in a terminal program. When the meter
wakes up, the optical surface is exposed by the Bio-wiper’s™ counter-clockwise rotation.
If power is shut off in mid cycle, the Bio-wiper™ will reinitialize to the beginning of the user-
selected settings when power is applied again.

ECO FL User’s Guide (FL) Revision AN 4 June 2012 9
3.4 Deployment
WARNING!
Battery-equipped units:
Always check vent seal plug for full insertion immediately prior to deployment.
Caution
The meter should be mounted so the LED source will not “see” any part of a cage or
deployment hardware. This will compromise the sensor’s output.
Once power is supplied to the ECO meter, the unit is ready for submersion and subsequent
measurements. Some consideration should be given to the package orientation. Do not face the
sensor directly into the sun or other bright lights. For best output signal integrity, locate the
instrument away from significant EMI sources.
Other than these basic considerations, one only needs to make sure that the unit is securely
mounted to whatever lowering frame is used and that the mounting brackets are not damaging the
unit casing.
3.5 Upkeep and Maintenance
We highly recommend that ECO meters be returned to the factory annually for cleaning,
calibration and standard maintenance. Contact WET Labs or visit our website for details on
returning meters and shipping.
After each cast or exposure of the instrument to natural water, flush with clean fresh water,
paying careful attention to the sensor face. Use soapy water to cut any grease or oil
accumulation. Gently wipe clean with a soft cloth. The sensor face is composed of ABS plastic
and optical epoxy and can easily be damaged or scratched.
WARNING!
Do not use acetone or other solvents to clean the sensor.
3.5.1 Bio-wiper™ and Faceplate Cleaning and Maintenance
The Bio-wiper™ and the copper faceplate need to be removed from the meter for thorough
cleaning to maximize anti-fouling capability.
1. Be sure the meter is NOT powered or connected to a power source prior to uninstalling
the Bio-wiper™ and faceplate.
WARNING!
Manually turning the motor shaft can damage the wiper motor and will void the warranty.
Make sure the Bio-wiper™ is loosened from the shaft before attempting to rotate it.

10 ECO FL User’s Guide (FL) Revision AN 4 June 2012
2. Remove Bio-wiper™: Use the factory-supplied 3/32-in. hex key to loosen the screw
that secures the wiper to the shaft on the instrument. It may be necessary to remove the
screw from the clamping hole and screw it into the releasing hole, tightening it just
enough to free the Bio-wiper™ from the shaft.
clamping screw hole
releasing screw hole
3. Remove faceplate: Use a small Phillips screwdriver to remove the screws that attach the
plate to the optics head.
WARNING!
Be sure to retain and re-use the factory-installed screws as they are vented for
pressure compensation.
4. Wash Bio-wiper™ and/or copper faceplate with soapy water. Rinse and dry thoroughly.
Note the condition of the copper on the instrument side of the wiper. It is normal for
copper to corrode and turn green, especially after the instrument has been removed
from the water. This corrosion will slightly reduce the wiper’s anti-fouling ability the
next time it is deployed.
5. Buff each with a pad of green Scotch Brite® (or similar) until shiny.
6. Clean the Bio-wiper™ shaft and the shaft hole using an isopropyl alcohol-saturated
cotton swab. Allow to dry.
7. Re-install faceplate.
8. Check the screw used to secure the Bio-wiper™ to the shaft: a hex key must fit
snugly into the screw socket. If the socket is in any way compromised, use a new
screw (4-40 x 3/8 in. 316 stainless steel treated with anti-seize. These are shipped
as part of the meter’s spare parts kit.)
9. Slide the Bio-wiper™ over the shaft. Be careful not to twist it on, thus rotating the
shaft. If the wiper does not slide on easily, insert the screw into the expander hole,
turning slowly until the Bio-wiper™ slides easily onto the shaft.

ECO FL User’s Guide (FL) Revision AN 4 June 2012 11
10. Rotate the Bio-wiper™ into the closed position.
11. Set the gap between the Bio-wiper™ and the instrument face to 0.03 in. (0.8 mm). An
improperly set gap will either fail to clean the face or cause the motor to draw
excessive current.
To gauge 0.03 in., fold a piece of paper in
half, then in half again, then fold a third time,
creasing the edges. It’s now 8 sheets and
about 0.03 in. thick.
Not enough flex.
Wiper may not be effective.
Proper flex.
Wiper maintains contact with
instrument face and
optical window.
Too much flex.
Wiper may cause too much
friction, using excessive
power.
12. Use the 3/32-in. hex key to tighten the screw to “finger-tight,” then snug an additional
quarter-turn.
13. Run the instrument to verify operation. The Bio-wiper™ must rotate 180 degrees to
clear the optics before sampling, and 180 degrees to cover the optics after sampling.
14. If the wiper needs adjusting, loosen the screw, make any necessary adjustments, and
repeat steps 9 through 13 to ensure the wiper is performing properly.

12 ECO FL User’s Guide (FL) Revision AN 4 June 2012
4. FLB and FLSB: Using Internal Batteries
ECO sensors powered with internal batteries can either run directly from the internal batteries or
can operate from power supplied by an external DC power supply (7–15 volts). Internal-to-
external source conversion is facilitated by a jumper plug that plugs into the unit’s bulkhead
connector. When inserted, the plug forms a connection from the battery to the electronics power
supply. By removing the plug, the instrument can be powered and communicate via a test or
deployment cable. Setup conditions, instrument checkout, real-time operation, and data
downloading are thus all achieved identically to the methods prescribed for the FL and FLS units.
4.1 Removing End Flange and Batteries
WARNING!
Changing the batteries will require opening the pressure housing of the ECO sensor. Only
people qualified to service underwater oceanographic instrumentation should perform this
procedure. If this procedure is performed improperly, it could result in catastrophic
instrument failure due to flooding or in personal injury or death due to abnormal internal
pressure as a result of flooding.
WET Labs Inc. disclaims all product liability from the use or servicing of this equipment.
WET Labs Inc. has no way of controlling the use of this equipment or of choosing qualified
personnel to operate it, and therefore cannot take steps to comply with laws pertaining to
product liability, including laws that impose a duty to warn the user of any dangers
involved with the operation and maintenance of this equipment. Therefore, acceptance of
this equipment by the customer shall be conclusively deemed to include a covenant by the
customer to defend and hold WET Labs Inc. harmless from all product liability claims
arising from the use and servicing of this equipment. Flooded instruments will be covered
by WET Labs Inc. warranties at the discretion of WET Labs, Inc.
1. Make sure the instrument is thoroughly dry.
2. Remove the dummy plugs.
3. With connector end flange pointed downwards away from face, release seal from vent plug.
4. Remove moisture from vent plug area.
5. Using needle nose pliers, remove filament from end flange.
6. Lift flange from pressure housing until seal is broken. The jacking screws can be used to
“push” the flange from the pressure housing and then can be removed or left in the end
flange.
7. Remove any excess moisture from flange–can seal area.
8. Work end flange out of pressure housing and remove any residual moisture. Remove the
gray foam spacer and the neoprene insulator.

ECO FL User’s Guide (FL) Revision AN 4 June 2012 13
9. The battery pack is connected to the processor boards by a six-pin Molex connector: do
NOT pull too hard or far on the battery pack or it will come unplugged and the unit
returned to WET Labs.
10. Gently pull the white cord at the loop to remove the battery pack from the pressure
housing.
11. Remove the black plastic protectors from the ends of the long screws securing the batteries.
12. Loosen and remove the screws (3/16-in slotted driver).
4.2 Replacing End Flange and Batteries
1. Replace the batteries.
2. Re-install the screws:
 Align the groove in each of the plates so the six-wire extension bundle will fit in it
along its length.
 Be careful not to cross-thread into the bottom end plate nor to over-tighten the screws.
 If they are too tight, the fiber washers that act as separators between the batteries will
flex.
 Make sure there are equal amounts of screw threads protruding from the bottom end
plate when they are secure. This will ensure the pack is straight and will fit into the
pressure housing with no difficulty.
3. Re-install the black plastic protective covers on the ends of the screws.
4. Remove and check the pressure housing O-ring for nicks or tears. Replace if necessary.
Before re-installing, apply a light coat of vacuum grease on the O-ring.
5. Carefully replace the battery pack in the pressure housing. Place the neoprene insulator on
the battery assembly and lay the white cord on the top.
6. Plug in the two-pin, then the six-pin Molex connectors. Sensor operation can now be tested
if desired.
7. Align the hole in the end flange (NOT the jack screw holes) with the white dowel pin.
While coiling the six wire bundle and making sure none are pinched between the end
flange and the pressure housing, position the flange on the housing. Leave space to re-
insert the gray foam spacer, making sure the cut-out accommodates the vent plug screw.
8. Push the end flange all the way on to the pressure housing, making sure no wires are
pinched. Be sure the vent plug does not pop up. If it does, you’ll need to re-position the
foam spacer.
9. Re-insert the monofilament.

14 ECO FL User’s Guide (FL) Revision AN 4 June 2012
4.3 Checking Vent Plug
If there is fouling on the vent plug, it should be cleaned and the two 010 O-rings replaced.
Otherwise, this mechanism should be maintenance-free.
WARNING!
The pressure housing is made of plastic material that scratches easily. Do not
let the screwdriver slip and scratch the can when removing or replacing the
vent plug. Use a toothpick (something softer than the plastic) to remove the
O-rings from the vent plug.
1. Pull vent plug out about half way; hold plug while unscrewing the truss screw. When screw
is removed, pull vent plug from end flange.
2. “Pinch” bottom O-ring around vent plug to form a small gap you can work a toothpick into.
Use the toothpick to help roll the bottom O-ring off the plug.
3. Perform the same procedure with the top O-ring.
4. Clean the vent plug and vent plug hole using a dry lint-free tissue or cotton swab.
5. Lightly coat two undamaged or new O-rings with silicon grease. Install the top O-ring
(nearest to large end of plug) first, then the bottom one.
6. Insert vent plug into its hole in the end flange and hold it while inserting the truss screw.
Rotate the vent plug to begin tightening the screw. Finish tightening using a screwdriver,
being careful not to overtighten truss screw.
Note
A portion of the truss screw head has been removed to allow for venting in case of
pressure buildup.