Smith-Root LR-20 Series, LR-20, LR-20B User Manual

USER'S GUIDE

LR-20 SERIES

BACKPACK ELECTROFISHERS

09441.09 LR-20 Series Manual

USER'S MANUAL

BACKPACK ELECTROFISHERS

LR-20 SERIES BACKPACK ELECTROFISHER

LR-20 SERIES

Operation and maintenance

For Models LR-20 (200W) and LR-20B (400W)

CONTENTS

Introduction .................................................................................1

Overview

Controls & Connectors

Battery Installation

Packframe

Cable Strain Relief Clips

Operation

Safety Features

Batteries & Charging

Charging

Battery Maintenance & Diagnostic equipment

Electrofishing Safety

Quick Release System

APPENDIX

A. Model 12/15-D Settings Chart ..................................... 23

B. Specifications

C. Glossary

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........... 17

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Items manufactured by companies other than Smith-Root carry the original manufacturer’s warranty. Please contact product
manufacturer for return instructions.

All Smith-Root, Inc. manufactured products are covered by a one-year warranty.

Credit & Refund Policy: Customers returning equipment, in new condition, will be given credit within ve days from the date of the return. A
must accompany returns. Valid equipment returns include, but are not limited to, ordering incorrect equipment, funding decits, and defective equipment returned for
reimbursement. All returns are subject to a restocking fee and applicable shipping charges. The restocking fee is gured at 10% of the purchase price but not less than
$20.00. Customers receiving equipment in damaged condition will be referred to the shipping company for insurance reimbursement.

09441.09 LR-20 Series Manual, © 2018 Smith-Root, Inc. Vancouver, WA - USA •

return authorization

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USER’S GUIDE

INTRODUCTION

The LR-20 Series Backpack Electrofisher offers

the safety and ruggedness of the LR-24 with the reliability of our classic
Model 12, while using the accessories of our standard LR-24. The LR­20B is an ideal transitional unit from our classic Model 12; it shares many
conventions as well as the safety and reliability and accessories of the LR-

24.
Use them for light-duty electrofishing or in conjunction with LR-24 units for

wider field applications. The LR-20B is a good addition to your collection of
Electrofishers in order to cover all field conditions.

SAFETY FEATURES:

• Emergency shut-down switch disables the unit

• Flashing red output warning light

• Audible output warning system

• Tilt sensor

• Water immersion turns output off

• Electrode out of water output off

• Pole mounted operator switch

• Non-conductive case

• Quick release shoulder harness and waist belt

1 2018

LR-20 SERIES BACKPACK ELECTROFISHER

OVERVIEW

OVERVIEW

Take the time to familiarize yourself with the LR-20's features before electrofishing.

H

J

I

B

K

F

G

C

D

B

O

A

L

M

L

O

N

R S

E

P

Q

FEATURES

Left:

A. Pack Frame
B. Cover Latch (2)
C. Front Cover
D. Cover Latch Sensor
E. Cable Strain Relief Clip
F. Battery
G. Battery Connector

Upper Right:

H. Shutdown Switch
I. Output Frequency Adjustment
J. Duty Cycle Adjustment

K. Timer Reset/Menu Select Button
L. LCD Display
M. Voltage Range Switch
N. Warning Light
O. Audio Alarm

Bottom Right

P. Cathode Connector
Q. Battery Cable Strain Relief
R. Control Connector
S. Anode Connector

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TIMER

PUSH

TO RESET

USER’S GUIDE

OVERVIEW (CONT.)

OUTPUT FREQUENCY: controls
the output frequency or pulses

DUTY

V
O
L
T
S

CYCLE

per second of the electrofisher.
DUTY CYCLE: Controls the

percentage of time the output
pulse is on out of the time from

FREQUENCY

the start of one output pulse to
the start of the next output pulse.
It also selects Burst of Pulses.

Duty Cycle and Output Frequency

TIMER RESET: Resets the
seconds counter display to zero.

LCD DISPLAY: Shows the number
of seconds the output of the unit
has been active since the last
timer reset, the peak output
voltage and current, the average
battery voltage and current, a fuel
gauge type display of the battery
voltage, heat-sink temperature

OUTPUT CONTROL

50

40

60

45

35

70

40

30

80

35

25

90

30

20

100

25

15

110

20

10

15

120

5

10

FREQUENCY DUTY CYCLE

DC

45

and waveform settings.

50

60

70

AUDIO ALARM: Provides loud

80

2 PULSES
3 PULSES

GATED BURST

audio warning whenever 30 volts
or more are present between

CLOCKWISE: LCD display; Power/
Emergency Shutdown Button;
Output Frequency and Duty Cycle
switches; Cover Latch.

the anode and cathode and also
when the unit is first switched
on and beeping increases in
frequency as loading increases.

WARNING LIGHT: Flashes once
per second whenever 30 volts
or more are present between
the anode and cathode and also
when the unit is first switched
on, and flashes faster as loading

A B C D

increases.

EMERGENCY SHUTDOWN

E

SWITCH: Turns unit on when the
red button is rotated clockwise
and in the up position. Pushing

LEFT TO RIGHT: A: Cathode
connector; B: power cord; C:
control connector; D: anode
connector; E: immersion sensor.

3 2018

down on the button shuts the
unit off in emergency shut-down
situation.

VOLTAGE RANGE SWITCH:
Controls the output voltage
of the electrofisher. Voltages
between 50 and 990 volts may
be selected.

IMMERSION SENSOR:

Automatically turns the output
off when water bridges the
sensing contacts.

ANODE CONNECTOR: Provides
the high voltage connection for
the anode electrode.

CONTROL CONNECTOR:
Provides the low voltage control
connection to the pole switch.

CATHODE CONNECTOR:
Provides the high voltage
connection to the cathode
electrode.

BATTERY CONNECTOR:

Provides power to the unit from
the battery.

COVER LATCH AND SENSOR:
Two over-center toggle latches
secure the front cover. Cover
must be closed and latched
before the output of the unit can
be activated.

LR-20 SERIES BACKPACK ELECTROFISHER

CONTROLS & CONNECTORS

EXTERNAL CONTROLS,
CONNECTORS AND SENSORS

ON/OFF SWITCH: Located on top

of the electrofisher enclosure. To
turn the power on, the user must
rotate the switch 90 degrees
in the direction of the arrows
(clockwise). To turn the unit off,
press down on the button.

ANODE CONNECTOR: Located
on the bottom right corner of
the electrofisher the large black
2 socket connector provides the
high voltage connection for the
anode electrode. This connector
has a locating lug that assures
the anode pole can only be
connected one way. The proper
connection for the anode pole
is with the cable pointing away
from the backpack.

BATTERY POWER CONNECTOR:
Located on the bottom left center
of the electrofisher this red and
black color coded connector
provides power to the unit from
the battery*. To connect a
battery to the electrofisher,
match the colors on the battery
connector to the colors on the
battery's connector, red to red
and black to black**.

*CAUTION: Before con­necting or disconnecting

a battery to the unit, make
sure the power switch is in the off
position, failure to do so may cause
damage to the battery and the elec­trofisher.

**WARNING: Reversing the
connectors will damage the
electrofisher and may cause
serious injury or death.

CATHODE CONNECTOR:
Located on the bottom left
corner of the electrofisher the
large black 2-socket connector
provides the high voltage
connection to the cathode
electrode. This connector has
a locating lug that assures
the cathode can only be
connected one way. The proper
connection for the cathode is
with the cable pointing away
from the backpack.

CONTROL CONNECTOR:
Located on the bottom right
center of the electrofisher the
small black 4-socket connector
provides the low voltage
control connection to the pole
switch. This connector has
a locating lug that assures
that the control connector

can only be connected one
way. The proper connection
for the control connector
is with the cable pointing
away from the backpack.
IMMERSION SENSOR: Located
on the bottom left corner
of the enclosure behind the
cathode connector. The
output of the electrofisher
is automatically deactivated
when these contacts come
in contact with water.
NOTE: Although the
immersion sensor is located
above the battery tray of
the LR-20, do not submerge
the battery; doing so will
cause damage to the battery
and the electrofisher.

NOTE: The front cover must
be closed and latched before
the output of the unit can be
activated.

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USER’S GUIDE

CONTROLS & CONNECTORS (CONT.)

FRONT PANEL CONTROLS AND INDICATORS

output of the LR-20 has been active
since the last timer reset, the output
voltage and current and a fuel
gauge type display of the battery
voltage. The backlight of the LCD
display is always on when the
electrofisher is on; this allows easy
viewing of the display even in deep
shadows without the need to open
the front cover and turn on another
switch.

VOLTAGE RANGE SWITCH:
Located on the left side of the
front panel. This 11-position switch
controls the output voltage of the
electrofisher. Voltages between 50
and 990 volts may be selected.

WARNING LIGHT: Located in the
bottom center of the front panel.
Wide viewing angle, high brightness
red LED's flash once per second
whenever 30 volts or more are
present between the anode and
cathode and also when the unit is

LR-20/LR-20B FRONT PANEL - Top to bottom, left to right: Frequency, Duty
Cycle knobs; Timer Reset Button; Display Window; Voltage Range Switch; Audio
Alarm; Warning Light.

TIMER RESET: Located on the upper
right corner of the front panel. This
switch allows the user to reset the 6
digit seconds timer back to 0.

DUTY CYCLE: Located on the
upper left center of the front panel.
This switch controls the percentage
of time the output pulse is on out of
the time from the start of one output
pulse to the start of the next output
pulse. When the duty cycle is set
to DC, the electrofisher puts out a
constant DC voltage determined by

the voltage range switch.
FREQUENCY: Located on the upper

left of the front panel. This switch
controls the output frequency
or pulses per second of the
electrofisher. When the duty cycle
switch is set to DC, Gated Burst 2
pulse or Gated Burst 3 pulse, this
switch has no effect on the output
of the electrofisher.

DISPLAY: Located in the top center
of the front panel. The display
shows the number of seconds the

first switched on.
AUDIO ALARM: Located on the

right side of the front panel. A
high volume audio alarm with
volume shutters provides additional
warning whenever 30 volts or more
are present between the anode
and cathode. In addition, the beep
rate gives an indication of the
power being drawn by the unit. It
also sounds when the unit is first
switched on.

5 2018

LR-20 SERIES BACKPACK ELECTROFISHER

BATTERY INSTALLATION

BATTERY INSTALLATION AND SAFETY

BATTERY INSTALLATION

To ensure operator and unit safety, as well as the life of the battery, care must be taken to make sure
that the battery is installed correctly.

The easiest way to install the battery is to place the electrofisher on the ground (or similar safe, dry
surface), rather than on the operator's back.

A. Start by placing the LR-20B on the ground, orienting the battery inside with its bottom on the

wall towards the packframe and centering it towards the bottom.

B. Lay the battery inside the battery tray handle up, so that the power connectors are closest to the

control box.
C. The handle should fit inside the corresponding notch in the front of the tray.
Pass the battery strap through the oval handle cutout and secure the clasp while taking up any slack

in the strap. It should be snug and not allow the battery to move.

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USER’S GUIDE

PACKFRAME

The packframe allows for various positions of the shoulder straps and waist belt to fit most people.
The straps and belt all have quick release latches that allow the Electrofisher to be removed quickly
if the operator falls into deep water or becomes injured*. For more information regarding emergency
quick release procedure, see Quick Release System on page 22.

Shoulder Strap
Adjustment

Chest Strap
Quick Release

Right Cable
Relief Clip

Waist Belt
Quick Release

Shoulder Strap

Pack Frame

Padded Waist Belt

Left Cable
Relief Clip

*WARNING: Always unfasten the chest strap of the pack before crossing or entering the water. Should
you fall into deep water, the chest strap may prevent you from removing the electrofisher quickly.

CABLE STRAIN RELIEF CLIPS

These clips are designed to prevent the anode and cathode
cables from traveling beyond their recommended range of
motion and to relieve undue strain on the connector plugs.
Make sure that the ring-mounted swivel clip on either side of
the packframe is attached to the electrode cables as shown
in Fig. 1. Using the rings and clips in the manner indicated will
transfer the weight of the electrode cables to the packframe
and offset the possibility of damaging either cable or their
respective connectors.

WARNING: Without Cable Strain Relief Clips, the anode and cathode connectors
or their cords could become damaged.

7 2018

Fig. 1

LR-20 SERIES BACKPACK ELECTROFISHER

OPERATION

OPERATION

Make sure the Electrode ring is clean and shiny. A cloudy,
dull-gray Electrode ring will reduce your catch per unit
effort and will increase the injury rate of fish. Initial setup of

voltage, frequency, and duty
cycle should be done outside
of your sample area to avoid
influencing your statistics.

1. Make sure the power button
on top of the control unit is
in the off position (Down).

2. Attach the anode and cath­ode to their output connec­tors.

3. Attach the smaller connec­tor on the anode cable to
the control connector of
the unit.

4. Be sure you know the loca­tion of the quick release
buckles for the backpack,
and unlatch the chest strap
before entering or crossing
the water.

5. Check with each crew
member to be sure they
know you are ready to turn
on the power.

ing forward until the tilt
switch activates, (about
55 degrees), and the tilt
message appears on the
display. Straighten up and
the status display should
return. If the tilt message
does not appear, do not use
the electrofisher; send it to
Smith-Root for repair.

8. Place a dampened cloth on
the immersion sensor con­tacts located on the lower
left-hand corner of the con­trol unit's box, behind the
cathode connector. The
display should show the
immersion warning. When
the cloth is removed and
the power is turned off and
back on, the display should
return to the status screen.
If the immersion message
does not appear, do not use
the electrofisher; send it to
Smith-Root for repair.

Power Button

Anode & Cathode Connectors

6. Connect the battery. When
using a lithium battery,
Attach the multicolored
lithium adapter (part #

10791) to the battery and
attach the red and black
connector pair from the
adapter to the red and
black connector pair on
the LR-20B.

7. Turn on the power. Do not
press the anode switch.
Check the operation of
the tilt switch by bend-

9. Set the frequency, duty
cycle, and voltage switches
to the values you wish to
use. If you don't know
what values to use, set the
switches as shown below
and follow the procedure
in the next step. NOTE: The
front cover of the electro­fisher must be closed to
activate the output.

• Frequency 15 Hz.

• Duty cycle 10 percent.

• Voltage 50 volts.

Battery Connector

Immersion Sensor

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USER’S GUIDE

OPERATION

Front Panel details

OFF

ON

Electrode Pole Safety Switch

10. Duty cycle and frequency
can have a huge impact
on taxis. Do not be timid
about changing these set­tings. In general, lower
frequencies are safer for
larger fish than higher fre­quencies. If you are not
getting any response from
fish at all, then change the
settings as follows:

a. Increase the voltage

switch one position, and
try again. Stop increas­ing voltage when you
begin getting a forced
response (twitch) from
the fish when you press
the anode pole switch.

b. If fish are not showing

taxis, then increase the
duty cycle switch one
position, and try again.
If necessary, repeat
this step until you elicit
taxis in the fish. If you
increase the duty cycle
to maximum and still
are not getting taxis,
then reduce the duty
cycle back to 10% and
go to the next step.

c. Increase the frequency

switch one position,
and try again. If neces­sary, go back to step
“a” before increasing
frequency again.

9 2018

LR-20 SERIES BACKPACK ELECTROFISHER

SAFETY FEATURES

EMERGENCY SHUTDOWN
SWITCH

The large red mushroom
switch located on the top
of the LR-20 is the Emer­gency Shutdown Switch,
which is also the main on/off
switch for the unit. To turn
the power on, the user must
rotate the switch 90 degrees
in the direction of the arrows
(clockwise). Since the switch
knob must be rotated, it
helps to prevent accidentally
powering up the unit. Push­ing the red mushroom knob
down until it latches will
immediately turn the unit off.

FLASHING RED LIGHT

Bright, long-life LED lamps
flash whenever the unit is
turned on and 30 volts or
more is present between the
anode and cathode.

AUDIO ALARM

The audio alarm is located on
the front panel and indicates
2 different operating
conditions:

1. Presence of high voltage
in the water: Whenever the
anode and cathode are in
the water and more than 30
volts is present while the unit
is on, there will be an audible
tone emitted by the alarm.

2. Average power output level:

• From 0 to 49 watts the

audio tone pulses once per
second.

• From 50 to 99 watts the
audio tone pulses twice per
second.

• From 100 to 149 watts the
audio tone pulses three
times per second.

• From 150 to 200 watts
the audio tone pulses four
times per second.

The audio alarm's volume can
be adjusted by means of the
rotating bezel on the front.

PACK FRAME QUICK
RELEASE

The LR-20 and LR-20B have
an integral quick release pack
frame. Simply lift one of the
two tabs on the shoulder
straps while unlatching the
waist belt and shrug the entire
unit away. For more informa­tion, see QUICK RELEASE
SYSTEM on page 22.

CAUTION!:
Always unlatch
the chest strap

of the pack
before entering or crossing
water. If left latched, this
strap may prevent the user
from quickly removing the
LR-20B in the event of an
emergency, such as falling
into deep water (See Quick
Release System, page 22).

1

TOP: The Emergency Shutdown
Switch; MIDDLE: Flashing red
indicator light (1) and audio
alarm (2); BOTTOM: Audio alarm
showing volume adjustment bezel.

*FOR MORE COMPREHENSIVE SAFETY INFORMATION, GO TO SAFETY ON PAGE 18

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USER’S GUIDE

1

12

2

3

4

5

7 8

9

10 11

13

6

12

1. Power On-Off Button

2. Frequency Adjust Knob

3. Duty Cycle Adjust Knob

4. Timer Reset Button

5. LCD Menu Display

6. Front Cover

7. Voltage Range Selector

8. Audible Output Alert

For more information on front panel items, see Front Panel Controls and
Indicators on page 5.

11 2018

14

1716

15

9. Visual Output Alert Light

10. Cathode Connector

11. Anode Connector

12. Front Cover Latches

13. Control Connector

14. Battery Connector

15. Battery Handle

16. Anode/Cathode Strain Relief Clips

LR-20 SERIES BACKPACK ELECTROFISHER

BATTERIES

BATTERIES: BATTERY CARE AND MAINTENANCE

BATTERIES

The Universal Battery Char­ger (UBC-24) is designed to
charge lead-acid and lithium
batteries for the LR-24,
LR-20 Series (and earlier
Smith-Root 24V models)
Electrofisher Systems.
The UBC-24 is a charger tai­lored for maintenance-free
batteries as well as other
types of lead-acid batteries.
The UBC-24 has a fully auto­matic, three stage charge
sequence with an electroni­cally timed routine and a
desulfation mode.
Stage 1 - Constant Current
Mode. The charger starts
with maximum current until
the battery reaches a preset
voltage (red LED light).
Stage 2 - Timed Constant
Voltage Mode. The charge is
electronically controlled with
a fixed voltage ceiling which
prevents excess battery gas
emission and over-charging
(orange LED light).
Stage 3 - Final Mode. Battery
is fully charged (green LED
light).
Full electronic protection is
provided against short circuit
and reverse battery connec­tion.

CHARGING

READ THESE
INSTRUCTIONS BEFORE
USING THE CHARGER

The battery charger is
only designed for indoor
use and should not come
into contact with water
or dust. In order to avoid
overheating, the charger
should not be covered when
it is in use.

Chargers filled with molding
material are splash-proof,
but must not be immersed
in water.

The socket should be easily
accessible. If an operational
error occurs, the plug
should be immediately
removed from the socket.
The charger contains
dangerous voltages and
the cover should not be
removed. All service or
maintenance work should
be carried out by qualified
personnel who can get
assistance by contacting
the manufacturer’s agent. A
fuse protects the product
against short-circuiting
and overloading. The
charger is designed for

charging lead batteries.
For safety reasons,
individual battery types
should have a minimum
capacity. Recommended
battery capacity: 6V
4-12Ah, 12V 3-12Ah, 24V

1.5-12Ah. Contact the
battery manufacturer for
the specific battery. Do not
attempt to charge batteries
that are not rechargeable.

CAUTION: Old, sulphated batteries usually have a reduced capacity and are difficult
to charge. The charge current will fall quickly as if the battery had received a full
charge. Even though a battery in this condition should be replaced, it will retain a
small charge.

12www.smith-root.com

BAT-01

UBC-24

From AC

Battery

Under

Test

USER’S GUIDE

BATTERY CARE AND MAINTENANCE (CONT.)

HOW TO CHARGE BATTERIES

1. The charger and battery should be placed in a well­ventilated area during charging.

2. Do not connect the charger to the socket before it is
connected to the battery.

3. Verify that the polarity is correct and connect the
charger cable: Red to red; black to black (use provided
adapter for lithium batteries).

4. Connect the charger to the socket.

5. When charging is finished, do not leave battery on
charger for an extended period of time. Disconnect
the charger from the socket before you disconnect the
charger from the battery.

LITHIUM BATTERY ADAPTER

The provided lithium battery adapter
must be used with the UBC Charger to
charge lithium batteries.

SPECIFICATIONS

Input Rating:

Maximum Output

Input Connection:

Connection: Battery clips

Dimensions/

Weight:

Power: 60W

Output

Nominal
90-264VAC/47­63Hz

3 pin IEC 320
(input cordset not
included)

5.31” x 3.15” x 1.73”
(135 x 80 x 44mm)/

0.77 lbs. (350g)

WARNING: Explosive gases can arise while
charging. Avoid sparks and open flames.
Verify that there is adequate ventilation
while charging. The charger should not

be used in the vicinity of flammable gases.
Avoid chargers with plastic casing coming into contact
with oils, grease, etc., as most types of plastic can be
broken down by chemicals and solvents.

LEDS INDICATE FOLLOWING CHARGE STATUS:

CONSTANT CURRENT MODE

• The charger is in constant current mode. LEDs change to
red.

• Charge current is at its maximum.

TIMED CONSTANT MODE

• The charger is in constant voltage mode. LEDs change

to orange.

• Charge current is less than its maximum.

• The battery is normally 80-95% charged.

• The charger stays in this mode until the charge current

decreases to charge termination level.

FINAL MODE

• The battery is fully charged. The LED changes to green.

UBC-24 BATT. CHARGER

Part Number .....................10167

• Remove battery from charger.

13 2018

BATTERIES

The electrofisher uses a 24
volt sealed deep cycle battery.
Understanding the proper
care of this battery will reduce
problems in the field.

Batteries should never
be allowed to remain in a
discharged state and should be
recharged as soon as possible
after use. Batteries should be
charged until the green lamp
on the charger comes on, then
removed from charger.

Charging Problems: Some
older batteries may not charge
within 24 hours. If a battery
has been left in a discharged
condition for a while, it may not
take a charge. If you suspect
that the battery has been
left discharged, charge it for
48 hours and then discharge
it with the electrofisher. If
the battery is not taking a
charge, it will not operate the
electrofisher for very long.
Sometimes by cycling the
battery a few times it will start
taking a charge again.

Note that all batteries should
be charged after each use even
if the battery was only slightly
discharged (these batteries

LR-20 SERIES BACKPACK ELECTROFISHER

BATTERIES

BATTERY CARE AND MAINTENANCE (CONT.)

do not have a memory). Total
number of charge/discharge
cycles possible varies inversely
with depth of discharge on
each cycle. Over-discharging
or completely discharging the
battery will greatly reduce
the cycles possible and a
battery left in a discharged
condition may be ruined. For
this reason, batteries should
never be allowed to remain in
a discharged state. Recharge
as soon as possible after each
use, and every three months if
unused.

Service Life: Batteries
which have been properly
maintained should last
3 to 5 years depending on
ambient temperature, depth
of discharge (D.O.D.), and
number of cycles (for Smith­Root batteries to maintain at
least 80% of original capacity,
they are rated 230 cycles for
100% D.O.D., 470 cycles for
50% D.O.D. or 1100 cycles for
30% D.O.D.). Batteries which
have reached this end of life
condition may still be useful
where shorter operating times
are appropriate.

SRI BATTERIES

A.

B.

C.

D.

Lithium Battery Adapter

24V 12

24V 9.6 Ah

Ah

24V 7 Ah

Shipping: Lead-Acid batteries (A & B above) conform to the UN2800
classification as "Batteries, wet, non-spillable, electric storage". They conform
to the International Air Transport Association (I.A.T.A.) Special Provision A67,
classifying them as non-dangerous goods and are therefore exempt from the
subject regulations for dangerous goods and are acceptable for transport
on both cargo and passenger aircraft. Lithium batteries (C above) are only
acceptable on ground transport and must have adapter (D above) removed.

Reference: I.A.T.A. Dangerous Goods Regulations, 35th Edition, Jan 1, 1994 Section 4.4, Special Provisions.

MODELS:

A. 24V 12Ah Lead-Acid Battery...

Ah Lead-Acid

B. 24V 7

C. 24V 9.6Ah Lithium Battery

D. Lithium Battery Adapter

Battery ......06681

........ 10765

............. 10791

06682

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USER’S GUIDE

BATTERY CARE AND MAINTENANCE (CONT.)

BATTERY STORAGE

INSTRUCTIONS

Fully charge batteries
before placing in storage.
As these batteries will self
discharge, we recommend
that they be recharged
after 3 months of storage.

Batteries removed
from storage should be
recharged prior to placing
back in service.

When not in use, store the
charger indoors in a cool
dry place.

MAINTENANCE
AND CLEANING OF
CHARGER

Very little maintenance
is required other than
protecting the charger from
damage and weather.

1. Coil cord when not in use.

BATTERY TIPS & PRECAUTIONS

1. Keep the battery charged! The most frequent cause of
battery failure is not recharging after each use.

2. Extreme temperatures kill batteries. Avoid storage
in exceedingly warm, or cold areas. Recommended
operating temperatures are between 5 and 35 degrees
C (maximum - 15 to 50 degrees C). The energy
available on a given discharge cycle decreases at low
temperatures and increases at higher than normal
temperatures. Increased temperatures increase the
gradual processes of very slow corrosion which normally
occur in all lead-acid batteries.

3. Avoid heavy vibrations or shocks, which may cause
internal damage. Foam packing is cheap insurance.

4. Avoid contact with oils or solvents which may attack the
battery case (ABS plastic resin). Clean with soap and water
only.

5. Do not crush, incinerate or dismantle the battery. The
electrolyte contains sulfuric acid which can cause
serious damage to eyes and skin. Dispose of old
batteries at a battery recycler.

6. Do not leave battery on charger for extended periods of
time when battery reaches a full charge.

2. Clean case and cords with
a slightly damp cloth.

3. Examine cords for
damage periodically and
replace if necessary with
manufacturer approved
parts.

When using a lithium battery, Attach the multicol­ored lithium adapter (part # 10791) to the battery
and attach the red and black connector pair from
the adapter to the red and black connector pair on
the LR-20B.

15 2018

BATTERIES

LR-20 SERIES BACKPACK ELECTROFISHER

BATTERY CARE AND MAINTENANCE (CONT.)

BATTERY RATING

Batteries are rated at the current which will reduce
the voltage per cell to 1.67 volts in 20 hours. The
heavyweight battery has a 12 amp hour rating.
However its life at 100 watt continuous discharge
would be only 120 minutes. As the discharge
current is increased, the efficiency and relative
capacity decreases (Fig. 6.1).

BATTERY LIFE

Each time you cycle a battery it loses some of its
ability to take a charge. Deep cycle batteries are
capable of being charged and discharged from 100
up to 1,000 times, depending on the depth of the
discharge and the type of charger used. Service
life and shelf life are both adversely affected by
extreme temperatures.

BATTERY STORAGE

Batteries stored at room temperature will self­discharge at 3% to 6% per month. Storage
temperature above 20°C (68°F) should be
avoided. Shelf life can be increased by storing in a
climate-controlled environment. Batteries should
be fully charged before storing and should be
recharged every four months.

Life Load Capacity

20 hr 0.60A 12.0Ah

10 hr 1.05A 10.5Ah

5 hr 1.95A 9.7Ah

1 hr 7.20A 7.2Ah

30 min 12.00A 6.0Ah

15 min 20.00A 5.0Ah

Fig. 6.1: Relative capacity of 12Ah
deep cycle battery.

Fig. 6.2: Discharge curves for
12Ah and 7Ah batteries.

EFFECTS OF TEMPERATURE

The temperature at which a battery is used also
affects the relative capacity of the battery. In cold
weather the shocking time will be less and the
battery will have less capacity (Figs. 6.3 & 6.4).

Fig. 6.3: Effect of temperature
on battery life.

Fig. 6.4: Effect of temperature
on capacity.

16www.smith-root.com

USER’S GUIDE

BATTERY MAINTENANCE & DIAGNOSTIC EQUIPMENT

MC-24 MAINTENANCE CHARGER

T

he Smith-Root MC-24 Maintenance Charger (sold separately)
is specifically designed for lead-acid battery maintenance and
storage (not intended for use with lithium batteries).

Trickle charging optimizes battery shelf life by reducing cell
deterioration. Keeping batteries fully charged can greatly
increase battery life. The MC-24 eliminates the hassle of
shuffling batteries from shelf to charger and keeps batteries
properly charged and ready for service. With the built-in
battery evaluation load test function and maximum charge
indicators, you can see the state of charge and condition of

MC-24 Maintenance Charger

each battery and identify low charged and worn-out batteries.
Charging batteries using the MC-24 takes between two and
four days. It is also an excellent cost effective alternative to
purchasing multiple battery chargers because it can recharge
four batteries at once.

BAT-01 Battery Analysis Tool

AC

UBC Charger

BAT-01

Battery

Fig. 6.5 BAT-01 Battery Analysis
Tool

BAT-01 BATTERY ANALYSIS TOOL

The Battery Analysis Tool
conjunction with the UBC-24 Battery Charger (Fig. 6.5). It tests
all models (lead-acid and lithium) of 24V backpack batteries
and in a clear and concise manner gives the usable battery life
remaining.

This tool is not to be used during each charge/discharge
cycle, but rather is intended to be used a few times a year,
just prior to actually using the batteries. It may also be used
to accurately test any Smith-Root 24 Volt battery where the
battery condition is either unknown or is questionable.

In practice, the Battery Analysis Tool is plugged into a standard
Smith-Root UBC-24 and also the battery under test (use
provided adapter for lithium batteries). The battery will begin
to charge as soon as the charger is plugged in (Do not use an
MC-24 Maintenance Charger for this test).

MC-24 Maintenance Charger

(sold separately)

.................... 06811

operates in

BAT-01 Battery Analysis Tool.....................08041

17 2018

LR-20 SERIES BACKPACK ELECTROFISHER

SAFETY

ELECTROFISHING SAFETY

Electrofishing equipment uses voltages and currents that can be lethal to humans. The
operators must always keep in mind that the chance of receiving an electrical shock is multiplied
in or near water. If used properly and with good judgment, an electrofisher is perfectly safe; lose
respect for it and you can lose your life!

Electrical equipment used in a moist field environment is always subject to deterioration that
could lead to dangerous electrical shock. Field equipment is also subjected to vibration and
impact during transporting and while in operation. Often equipment shared by different crews
does not receive proper maintenance or a complete checkout.

Follow the safety guidelines and use good common sense to handle unforeseen circumstances.

PROPER EQUIPMENT

To prevent electrical shock, all electrical equipment should be carefully inspected before each
field operation. With all electrical equipment in good operating condition and all insulation
junction boxes, bonding, and connections intact, there is much less danger of receiving an
electrical shock.

MAKE SURE THAT:

• Electrofisher gives audible sound when voltage is present at anode.

• Quick release system is functioning properly.

• Tilt switch is functioning properly (turns power off).

• Dipnets with non-conductive handles are used in conjunction with properly rated (≥ 1,000V)
lineman gloves.

• Electrodes are free from corrosion (clean if necessary), Anode does not have netting attached
to ring, Make sure cathode is free of wear and burrs and its cable insulation is undamaged.

• Poles are free of cracks in fiberglass handle.

• Power Supply- check all batteries for damage / leakage (disconnect power supply before
transporting and when not in use).

• Always purchase electrofishing equipment from an authorized dealer.

18www.smith-root.com

USER’S GUIDE

ELECTROFISHING SAFETY (CONT.)

WHAT IS ELECTRICAL SHOCK?

It is the current that passes through
the human body that does the
damage. The voltage is relevant,
because it is the force that “pushes”
the current through the body.
Experiments show that 20 to 500 Hz
AC current is more dangerous than
DC, or higher frequencies of AC.

The voltages used by electrofishing
gear can cause death by one of three
means:

VENTRICULAR FIBRILLATION

Ventricular fibrillation is
uncoordinated contraction of the
muscles of the heart. The heart
quivers rather than beats. Electrical
current through the chest can cause
this condition. Once a person goes
into ventricular fibrillation, the
only way to stop the quivering is
to use a defibrillator that applies a
pulse shock to the chest to restore
heart rhythm. Cardiopulmonary
resuscitation may help to keep
a victim alive until they can be
defibrillated.

RESPIRATORY ARREST

The respiratory center is at the base
of the skull. Thus, shocks to the head
can cause the breathing to stop.
Artificial respiration by the mouth-to­mouth method should be used in this
case.

ASPHYXIA

Asphyxia is caused by contraction of
the chest muscles. When a current
is above a certain level, a person
cannot let go of an electrically hot
wire. Currents above this level may
not cause ventricular fibrillation, but
may be enough to cause contraction
of the chest muscles. If the current
is not stopped, or the victim is not
removed from the point of electrical
contact, asphyxia will result. Artificial
respiration or cardiopulmonary
resuscitation may be necessary.

PERSONAL PROTECTIVE EQUIPMENT

• First aid kit.

• Non-breathable chest waders or non-breathable
hip boots with non-slip soles.

• Lineman electrical gloves rated and tested at a
minimum of 1,000 volts.

• Check personal protective equipment for leaks
and holes.

OPTIONAL:

• Brimmed hat

• Polarized sunglasses

• Life jacket and or wading belt

• Raincoat

CREW PREPARATION:

• Designate a crew leader.

• For safety reasons, there should be a minimum

of three person crews. Never electrofish alone.

CREW LEADER RESPONSIBILITIES:

• Designate 1 person to order power of the
electrofisher to be turned on.

• Clarify with the entire crew the location of the
nearest hospital and evacuation route in case of
an accident.

• Make it clear that any member of the crew can
order power off.

CREW RESPONSIBILITIES:

• All crew members should be trained in

fundamentals of electricity and safety.

• As electrofishing is inherently dangerous. All

crew should be alert and attentive; take breaks
as necessary.

EMERGENCY PLANNING

In case of an accident:

• Turn off power to the electrofisher

• Evaluate situation and take appropriate action

19 2018

LR-20 SERIES BACKPACK ELECTROFISHER

SAFETY

ELECTROFISHING SAFETY (CONT.)

PREVENTING ELECTRICAL SHOCK

Electricity needs to have a complete electrical circuit in order for current to flow. The only
way that someone can get shocked is if they become the electrical conductor to complete the
circuit. The current flows from the cathode to the anode through the water. The water is the
electrical conductor. If someone touched both the anode and the cathode, they would become
an electrical conductor and complete the circuit path and get a severe electrical shock.

10.0

5.0

1.0

0.5

Electrocution threshold for typical adult

0.1

Seconds

0.05

PULSE DURATION

0.005

0.001

0.01

0

40

20

0

100

80

60

CURRENT (Milliamps passed through chest area)

120

140

160

180

200

220

Maximum permitted by UL for class A ground fault interrupter
Typical ground fault interrupter

Maximum pulse duration for POW pulsators

240

260

Effects on humans of an electrical pulse passed through the chest area

WARNING: Touching any electrode is never recommended

while backpack electrofishing.

Preventing electrical shock means preventing electrical current from entering and flowing
through parts of the body. Rubber lineman’s gloves rated to at least 1,000V should always be
worn.

Even while wearing rubber gloves and waders, never touch an electrode while the circuit is
energized.

Do not work on the electrical system while the pack is plugged in.

A severe electrical shock from electrofishing gear may result in the need for artificial
respiration; therefore, it is imperative that no one ever works alone.

To prevent electrical shock, all electrical equipment should be carefully inspected before each
field operation. With all electrical equipment in good operating condition and all insulation,
junction boxes, bonding and connections intact, there is much less danger of receiving an
electrical shock.

20www.smith-root.com

USER’S GUIDE

ELECTROFISHING SAFETY (CONT.)

ELECTROFISHER OPERATION

1. Electrofish only as far as you can safely wade. Some areas
are unreachable with a backpack electrofisher.

2. Touching an active electrode is not recommended, even
while wearing Lineman gloves and waders.

3. Never electrofish with spectators on shore. Electric fields
can travel large distances through buried pipes, metal
culverts, and metal sheet piling.

4. If spectators show up during electrofishing, stop the
operation and go to explain to them what you are doing.
Explain the risks to them being there and ask them to
please leave for their own safety. If they refuse to leave,
stop electrofishing, load the equipment and leave the area.

WARNING: Operating this equipment in a manner not
specified in this manual, making modifications, or using
accessories not approved by Smith-Root, Inc. may impair
the protection offered by the equipment.

• Have electrical circuits checked only by qualified
technicians.

• Turn off the electrofisher before making any connections or
part replacements.

• Release chest strap before entering the water.

• Shut off power before entering or leaving the water.

• Stop work immediately if you get water in waders or gloves.

• Operate slowly and carefully to prevent slips and falls.

• Always be sure that all crew members are clear of
electrodes before turning power on and before energizing
electrodes.

• Do not operate an electrofisher if you have any prior heart
ailments, wear a pacemaker, or are pregnant.

21 2018

LR-20 SERIES BACKPACK ELECTROFISHER

SAFETY

ELECTROFISHING SAFETY (CONT.)

QUICK RELEASE SYSTEM

It may be necessary in some circumstances to remove the electrofisher backpack quickly.
Both the LR-24 and LR-20 have an integral quick release pack frame. Just press the latch tabs

on the waist belt and shoulder straps and the entire LR-24 falls away.

1 2

The following procedure illustrates how the quick
release system is designed to work:

1. Squeeze the release tabs on hip belt buckle to
remove hip belt.

3

4

2. Squeeze the release tabs on either shoulder strap.

3. With strap detached, shrug off opposite strap.

4. This will allow the pack to fall away from you very
quickly! Move away from pack as it falls.

CAUTION:

the pack before entering or crossing water. If left
latched this strap may prevent the user from quickly
removing the LR-24 in the event of an emergency,
such as falling into deep water. This should only be
done in an emergency situation! The backpack may
be damaged from contact with the ground and/or
water when using the quick release system.

Always unlatch
the chest strap of

22www.smith-root.com

Frequency

1

Period

=

Volts

Time

Width

Period

Standard pulse

USER’S GUIDE

APPENDIX A: MODEL 12-B/15-D SETTING CHART

Use this chart to convert settings used with the 12-B or 15-D to settings on the LR-20.

Example: If H2 were used with the model 12-B, the corresponding settings for the LR-20
would be 50Hz at 5% Duty cycle. Note that the LR-20 does not have pulse width settings.
See diagrams at left for an explanation of Duty Cycle, Output Frequency and Gated Bursts.

PULSE

V
O
L
T
S

WIDTH

FREQUENCY

Pulse width x Frequency x 100 = Duty Cycle in %

Duty cycle and Output Frequency

Width

Volts

Period

Between

Burst = 3 pulses

Burst rate

=

Period

Time

1

Gated Burst

Frequency 5 10 15 20 25 30 35 40 45 50 60 70 80 GB 2 Pulse GB 3 Pulse

STANDARD PULSES MODEL 12-B AND 15-D

Mode Switch 1 2 3 4 5 6

A

B

C

D

E

F

G

H

I

J

K

L

M

N

1Hz 2ms 3ms 4ms 6ms 7ms 8ms

5Hz 1ms 2ms 3ms 4ms 6ms 8ms

10Hz 500us 1ms 2ms 4ms 6ms 8ms

15Hz 500us 1ms 2ms 4ms 6ms 8ms

20Hz 500us 1ms 2ms 4ms 6ms 8ms

30Hz 500us 1ms 2ms 4ms 6ms 8ms

40Hz 500us 1ms 2ms 4ms 6ms 8ms

50Hz 500us 1ms 2ms 4ms 6ms 8ms

60Hz 500us 1ms 2ms 4ms 6ms 8ms

70Hz 500us 1ms 2ms 4ms 6ms 8ms

80Hz 500us 1ms 2ms 4ms 6ms 8ms

90Hz 500us 1ms 2ms 4ms 6ms 8ms

100Hz 100us 500us 1ms 2ms 4ms 6ms

110Hz 100us 500us 1ms 2ms 4ms 6ms

O 120Hz 100us 500us 1ms 2ms 3ms 4ms

DUTY CYCLE PERCENT LR-20/LR-20B

5ms 10ms 15ms 20ms 25ms 30ms 35ms 40ms 45ms 50ms 60ms 70ms 80ms 4Hz 4Hz

3.3ms 6.7ms 10ms 13.3ms 16.7ms 20ms 23.3ms 26.7ms 30ms 33.3ms 40ms 46.7ms 53.3ms 62.5ms 62.5ms

2.5ms 5ms 7.5ms 10ms 12.5ms 15ms 17.5ms 20ms 22.5ms 25ms 30ms 35ms 40ms @ 1Hz rate @ 1Hz rate

2ms 4ms 6ms 8ms 10ms 12ms 14ms 16ms 18ms 20ms 22ms 24ms 26ms 125ms 187.5ms

1.7ms 3.3ms 5ms 6.7ms 8.3ms 10ms 11.7ms 13.3ms 15ms 16.7ms 20ms 23.3ms 26.7ms 12.50%

1.4ms 2.9ms 4.3ms 5.7ms 7.1ms 8.6ms 10ms 11.4ms 12.9ms 14.3ms 17.1ms 20ms 22.9ms

1.3ms 2.5ms 3.7ms 5ms 6.2ms 7.5ms 8.7ms 10ms 11.3ms 12.5ms 15ms 17.5ms 20ms

1.1ms 2.2ms 3.3ms 4.4ms

1ms 2ms 3ms 4ms 5ms 6ms 7ms 8ms 9ms 10ms 12ms 14ms 16ms

0.8ms 1.7ms 2.5ms 3.3ms 4.2ms 5ms 5.8ms 6.7ms 7.5ms 8.3ms 10ms 11.7ms 13.3ms

0.7ms 1.4ms 2.1ms 2.9ms 3.6ms 4.3ms 5ms 5.7ms 6.4ms 7.1ms 8.6ms 10ms 11.4ms

0.6ms 1.3ms 1.9ms 2.5ms 3.1ms 3.8ms 4.4ms 5ms 5.6ms 6.3ms 7.5ms 8.8ms 10ms

0.6ms 1.1ms 1.7ms 2.2ms 2.8ms 3.3ms 3.9ms 4.4ms 5ms 5.6ms 6.7ms 7.8ms 8.9ms

0.5ms 1ms 1.5ms 2ms 2.5ms 3ms 3.5ms 4ms 4.5ms 5ms 6ms 7ms 8ms

0.5ms 0.9ms 1.4ms 1.8ms 2.3ms 2.7ms 3.2ms 3.6ms 4.1ms 4.6ms 5.5ms 6.4ms 7.3ms

0.4ms 0.8ms 1.3ms 1.7ms 2.1ms 2.5ms 2.9ms 3.3ms 3.8ms 4.2ms 5ms 5.8ms 6.7ms

5.6ms 6.7ms 7.8ms 8.9ms 10ms 11.1ms 13.3ms 15.6ms 17.8ms

10

15

20

25

30

35

40

45

50

60

70

80

90

100

110

120

23 2018

Overall Duty

Cycle

18.75%

Overall Duty

Cycle

LR-20 SERIES BACKPACK ELECTROFISHER

SPECIFICATIONS

APPENDIX B: SPECIFICATIONS

Conductivity Range:

Output Power:

Output Voltage

Ranges:

Output Frequency:

Output Duty Cycle:

Overload Protection:

Safety Features:

Timer:

Metering:

SPECIFICATIONS

10 to 1950 μS/cm (

LR-20B: 400W continuous, 39,600W peak;
LR-20: 200W continuous, 39,600W peak

50 to 990V in 11 steps (50 to 400V in 50V steps, 500V, 700V, 990V)

10 to 120Hz in 16 steps (10 to 50Hz in 5Hz
steps, 60 to 120Hz in 10Hz steps)

5 to 50% in 5% steps, 60 to 80% in 10% steps, Gated
Burst 2 pulse, Gated Burst 3 pulse, DC

Automatic electronic and 40A safety fuse, High output current,
Output voltage out of regulation, Over temperature

Emergency shut off switch, Output active super-high brightness
red LED, Output active audio alarm, Output off immersion sensor,
Output off tilt sensor, High output current protection, Pole mounted
output control switch, Electrode out-of-water shut down sensor,
Non-conductive lightweight pack frame, Quick release harness

6 digit computer controlled seconds counter
Mean current, Peak output voltage, Average output power,

Battery voltage, Battery current, Battery fuel gauge, Timer

microsiemens per centimeter)

Electrodes:

Battery:

Size and Weight:

Electrode pole, 6 ft. 2-piece pole, 6 ft. 1-piece pole; 6 in., 11 in., 18 in.
aluminum ring, 11 in. stainless steel ring; stainless steel trailing cathode

Choice of 24V sealed 7Ah or 12Ah lead-acid
or 9.6Ah lightweight lithium-iron

Height: 29.75 in; Width: 13.75 in; Depth: 13 in; Weight: 12.3 lb. (5.58 kg)

24www.smith-root.com

USER’S GUIDE

APPENDIX C: GLOSSARY OF TERMS

Amp:

Anode:

Cathode:

Conductivity:

Current:

Duty Cycle:

Electrofisher:

Frequency:

The unit of measure expressing the quantity of electricity flowing in a circuit.
Analogous to water quantity flowing in a pipe. Amp is an abbreviation for
Ampere.

The positive terminal on a battery or forward facing electrode on an LR-24.

The negative terminal on a battery or rear facing electrode on an LR-24.

A measure of the ease with which electricity can flow through a substance.
In electrofishing, the substance of interest is water. Conductivity is measured
in mS (micro-Siemens, or millionths of a Siemen). Distilled water has a
conductivity of 0 mS, while brackish water has a conductivity of 10,000 mS
or more.

Generic term that refers to the flow of electricity in a circuit. Unit of measure
is the Amp.

Expresses the ratio, in %, of on time for an electrical signal such as an LR-24
output. For example, if an LR-24 output is ON for .25 seconds and OFF for

0.75 seconds, the duty cycle is (0.25/(0.25 + 0.75)) x 100=25%.
An apparatus that applies electricity to a body of water for the purpose of

stunning fish.
The rate at which an electrical signal changes over time. The unit of measure

is the Hertz. One Hertz is equal to one change (cycle) per second and is
abbreviated Hz. For example, if an LR-24 is producing 60 pulses per second,
the frequency would be 60 Hz.

Hertz:

mA:

mSec:

NEMA:

The unit of measure for frequency. See Frequency.

Acronym for Ingress Protection. Various IP standards exist that specify the

IP:

ability of an enclosure to keep out contaminants such as dust and water. IP65
applies to the LR-24 enclosure and signifies that it is dust-proof and will protect
from a water-jet spray in all directions, but is not suitable for immersion.

Milliamp. One thousandth of an Amp; see AMP.

Millisecond. One thousandth of a second.

Acronym for National Electrical Manufacturers Association. NEMA sets
contamination protection standards that apply to the LR-24 enclosure.

Operational

Duty Cycle:

Volt:

Volt-Amp:

Watt:

Expresses the ratio in percentage of shocking time to battery power on time.

The unit of measure expressing the ‘pressure’ behind an electrical current.
Analogous to water pressure pushing water through a pipe.

Unit of measure of electrical power equivalent to the Watt. Abbreviated VA.

Unit of measure of electrical power. 1 Watt = 1Amp * 1Volt. Abbreviated W.

25 2018

S

i

n

c

e

1

9

6

4

[e-mail]
[phone]
Vancouver, WA USA

www.smith-root.com