Cool Air LBW-420-LEL User manual

Models
LBW-420-LEL (24 VDC powered)
Ammonia Leak Detector

P a g e | 1 Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
CAUTION & SYMBOL DEFINITIONS:
CAUTION: Gives detailed description of different
situations to avoid or not avoid for the proper operation of the
equipment.
WARNING: RISK OF ELECTRIC SHOCK. DO NOT
REMOVE COVER. NO USER SERVICEABLE
PARTS INSIDE. REFER TO QUALIFIED SERVICE
PERSONNEL.
AVIS: RISQUE DE CHOC ELECTRIQUE. NE PAS
ENLEVER LE COUVERCLE. AUCUN ENTRETIEN
DE PIECES INTERIEURES PAR L'USAGER.
CONFIER L'ENTRETIEN AU PERSONNEL
QUALIFIE.
AUTHORIZED DISTRIBUTOR:
GasDetectorsUSA.com
Houston, Texas USA
[email protected]
832-615-3588

P a g e | 2
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
TABLE OF CONTENTS
IMPORTANT—READ THIS FIRST...................................................................3
CAUTIONS.............................................................................................................3
AVOIDING NUISANCE ALARMS.............................................................................3
INTRODUCTION....................................................................................................4
STANDARD FEATURES......................................................................................4
AVAILABLE OPTIONS .......................................................................................5
PARTS DESCRIPTION ........................................................................................6
FRONT PANEL DISPLAY........................................................................................6
AMMONIA SENSOR ...............................................................................................7
FRONT PANEL-MOUNTED CIRCUIT BOARD .........................................................7
SERVICE JUMPER (SERVICE MODE).....................................................................8
THE “ENTER”, “UP”, AND “DOWN” PUSHBUTTONS .......................................8
ROTARY SELECTOR SWITCH................................................................................8
ENCLOSURE-MOUNTED CIRCUIT BOARD...........................................................10
POWER CONNECTIONS .................................................................................10
J3 SETTINGS.....................................................................................................10
RELAYS...............................................................................................................11
RELAY STATUS LEDS.........................................................................................12
EXTERNAL CONNECTIONS..................................................................................12
4–20 mA Analog Output............................................................................12
4 to 20mA WIRING………………………………13
Wiring Diagram: LBW-420-LEL 3 wire –24 VDC Power Supply…….13
Wiring Diagram: LBW-420-LEL 4 wire –24 VDC Power Supply…….14
INSTALLATION AND SETUP..........................................................................15
REMOTE ALARM LIGHT AND HORN UNIT............................................17
PROGRAMMING AND OPERATION.............................................................18
PROGRAMMING THE AMMONIA ALARM SET POINTS.........................................18
RESETTING THE RELAYS....................................................................................18
PROGRAMMING THE 4TO 20MARANGE ............................................................19
SETTING THE SERVICE MODE TIMEOUT............................................................19
TEST AND CALIBRATION...............................................................................20
TESTING THE DETECTOR....................................................................................20
CALIBRATING THE DETECTOR ...........................................................................21
TECHNICAL SUPPORT ....................................................................................22
WARRANTY........................................................................................................23
LBW-420 SPECIFICATIONS.............................................................................26

P a g e | 3
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
IMPORTANT—READ THIS FIRST
PLEASE READ AND UNDERSTAND THIS SECTION
BEFORE INSTALLING AND OPERATING THE LBW-
420-LEL DETECTOR
CAUTION:
After applying power, test the detector to ensure it is operating
correctly. Be sure the detector has been powered for at least 10
minutes before testing.
Do not store this manual inside the detector, as this
might result in damage to components from excessive
heat.
ADEQUATELY COVER THE DETECTOR SENSOR
DURING WASHDOWN, AND AVOID SPRAYING THE
WASHDOWN LIQUID DIRECTLY ONTO THE SENSOR
Avoiding unwanted Alarms or shutdowns
To avoid nuisance alarms, place the detector in service mode
before:
Programming the alarm set point.
Performing maintenance, repairs, testing, or calibration.
Performing refrigeration system maintenance.
Removing the ammonia sensor.

P a g e | 4
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
INTRODUCTION
The Cool Air Incorporated LBW-420-LEL Detector is a state-of-
the-art ammonia leak detector that detects and displays ammonia
concentrations of 0 to 9.9%. It comes equipped with a long-life
ammonia sensor that has a quick and accurate response to ammonia
concentrations.
The Cool Air Incorporated LBW-420-LEL has a fully isolated DC
to DC power supply, allowing the LBW-420-LEL to be powered
from the same DC supply as the 4-20 mA monitoring circuits
without concern for ground isolation.
The LBW-420-LEL requires a DC supply voltage between 18 and
36 volts DC.
The LBW-420-LEL can be configured to supply power to the 4-20
mA circuit(s) or can operate as a fully isolated 4-20 mA sensor.
Refer to 4–20 mA Analog Outputs for more details.
The Cool Air Incorporated LBW-420-LEL can be optionally
equipped with an AC to DC converter to allow operating the
detector with 100 to 240VAC input.
Once the detector senses ammonia at or above the ALARM set
point, the relays will activate and stay activated until a relay rest is
initiated (see “Resetting the Relays”)
STANDARD FEATURES
All LBW-420-LEL’s come with these additional standard features:
Programmable Alarm set point.
Selectable Service Mode timeout.
Range selectable 4-20 mA analog output signals, for
ammonia
Normally-open, normally-closed contacts for shutting
down compressors and closing valves.
A NEMA 4X, UL-listed enclosure.

P a g e | 5
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
AVAILABLE OPTIONS
A remote alarm light and horn box with a toggle switch to
TEST/NORMAL/SILENCE the alarm.
Contact Cool Air Incorporated technical support for more detailed
information, or for purchasing any of these options.

P a g e | 6
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
PARTS DESCRIPTION
Front Panel Display
The front panel display is comprised of a digital display and a series
of labeled indicating LED’s. The seven-segment, four-digit display
indicates a variety of information, such as ammonia concentration
and more, depending on the position of the rotary selector switch.
Ammonia concentration is displayed in percent ammonia. The
LED’s provide an indication of ammonia concentration and alarm
status at a glance.
Alarm indication
All Relays will be
active when this is on.
Alarm disabled
indication. All relays
will be deactivated when
this LED is on.
Two digit seven segment display.
In normal operating mode this
will display the ammonia
concentration. It will also be use
in setting options and calibration.

P a g e | 7
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Ammonia Sensor
The detector comes with a long-life sensor that has a high
sensitivity to ammonia with a quick response at levels above .1%.
Front Panel-Mounted Circuit Board
The front panel-mounted circuit board contains the controls
necessary for programming and operating the detector. Each
control is described in detail below. When the detector enclosure is
open, this circuit board is on the left, attached to the front panel.
NOTE: The service switch may be a jumper instead of the switch.

P a g e | 8
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Service Jumper (Service Mode)
The detector can be set to one of two modes: normal operating
mode or service mode. The detector is in normal operating mode
when the service jumper is in the “OFF” position. When the service
jumper is in the “ON” position, the detector continues to function as
usual, however the alarm, pre-alarm, and auxiliary relays are
disabled as well as the 4 to 20mA signal is set to 4ma (0%). This
allows the detector to be serviced, tested, and calibrated without
tripping the alarm relays and setting alarms or causing shutdowns.
When the detector is in the service mode, “Alarms Disabled” LED
will be illuminated (service jumper “on”). This is done as a
reminder to set the jumper back to “off” when service is done. If
the service jumper is not returned to off it will automatically return
to an as off state after a selected amount of time. The factory default
is 15 minutes.
See “Setting the Service Mode Timeout”
The “ENTER”, “UP”, and “DOWN” Pushbuttons
The “UP” and “DOWN” buttons are used for setting the digital
display to the desired value, and the “ENTER” button is used for
programming a value previously set on the digital display. These
buttons are used when programming: the set points, configuring
other options, they are also used during calibration of the detector.
Rotary Selector Switch
The rotary selector switch (labeled “MENU SELECT” on the front
panel-mounted circuit board) is used for performing functions such
as:
Setting the information displayed on the front panel
Programming set point
Displaying system information
Calibrating the detector
Resetting the relays
When the detector is in operation, this switch is typically set to
position “0” to continuously display ammonia concentration.

P a g e | 9
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Use the following chart to select the switch position for the desired
function:
To:
Set the Rotary
Selector Switch to:
Display ammonia concentration in percent
0
Display ammonia concentration in percent
1
Display the firmware revision
2
Program the ammonia alarm set point
3
Factory Use
4
Factory Use
5
Factory Use
6
Factory Use
7
Factory Use
8
Factory Use
9
Note: If the rotary selector switch is left in a position other than “0”
for more than 5 minutes, the digital display will begin to display
ammonia concentration. If this happens, return the selector switch
to the “0” position, then set the switch to the desired position. For
example, if you set the rotary selector switch to position “3” to
program the alarm set point, and if, after 5 minutes of inactivity the
display reverts to displaying ammonia concentration, move the
switch to “0”, then back to “3” to continue programming the alarm
set point.
Caution: Before closing the detector enclosure, be sure to
return the rotary selector switch to position “0” to
correctly display ammonia concentration.

P a g e | 10
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Additional functions are available through the rotary selector switch
when the jumper (labeled “SET1”), located below the rotary
selector switch on the front panel-mounted circuit board, is
installed:
To:
Set the Rotary
Selector Switch to:
Factory Use
0
Factory Use
1
Display the firmware revision
2
Program the ammonia sensor Range
3
Set the Service Mode Time out
4
Resetting the relays
5
Factory Use
6
Factory Use
7
Factory Use
8
Calibrate the detector
9
Enclosure-Mounted Circuit Board
The Enclosure Mounted Circuit board contains the relays, output
contacts and termination points for connecting to external
equipment. When the detector enclosure is open, this circuit board
is on the rear wall of the enclosure. The enclosure-mounted circuit
board is shown in the following picture and described in detail
below.
Power (LBW-420-LEL)
Power for the LBW-420-LEL must be a DC voltage between 18 and
30 volts with a current rating of at least 0.5 amps at 24 volts. Power
is connected to terminal block J2.
Jumper J3, Ammonia signal (LBW-420-LEL only)
Jumper J3 (ammonia signal) configures the LBW-420-LEL to use
either an external power supply for the Ammonia 4-20 mA circuit
or to use an on board 30-volt DC supply for the 4-20 mA circuits.
With the jumper in the leftmost position, connecting pins 2 to 3 (as
shown in the picture on the next page) 4-20mA power is supplied by
the on-board supply.

P a g e | 11
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
With the jumper in the rightmost position, connecting pins 2 to 1
(opposite of picture) 4-20 mA power must be supplied by an
external supply.
Jumpers Required
Jumpers J3 must be installed in either position. If the jumper is
removed, the 4-20 mA circuit(s) will not function.
Relays
The detector has three miniature printed circuit board relays: the
alarm, pre-alarm (early warning), and the auxiliary relays. In the
normal operating mode, the relays are energized in a normally-open
state. If a loss of power to the detector occurs, the relays will de-
energize and the alarms, if connected, will sound. When relays have
been activated by an alarm condition they will need to be manually
rest after conditions are returned to normal. (“Resetting the
Relays”)

P a g e | 12
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Relay Status LEDs
Each relay has a surface-mounted LED associated with it that
indicates the status of the relay. A relay is energized (a non-alarm
condition) when its LED is lighted (green), and de-energized (an
alarm condition) when the LED is not lighted.
External Connections
Contacts for external connections:
4–20 mA outputs for ammonia level
Auxiliary Relay contacts
Alarm Relay contacts
Pre-alarm Relay contacts
LBW-420-LEL DC Power
4–20 mA Analog Outputs
The detector has a 4-20 mA analog output that allows it to
communicate with external devices such as computers, PLCs, and
digital displays. The output conforms to ISA S50.01 ratings, Type
2L and Type 2H (two-wire).
The ammonia level detector output current (TB2, “Sensor 4-
20mA” terminals on lower left of Enclosure Mounted Circuit
Board) is proportional to ammonia PPM with the proportionality
constant dependent on the range. The PPM value can be determined
using one of the following formulae:
% NH3 = .041667 (I –4) 0 to 1% Range
% NH3 = .083334 (I –4) 0 to 2%Range
% NH3 =.4166667(I –4) 0 to 10% Range
Where % NH3 equals ammonia concentration in percent and I equal
the output current in mA. For example, if the current is 4 mA, then
the ammonia concentration is 0 %. If the current is 20 mA, then the
ammonia concentration is 1% PPM (1% range), 2% (2% range), and
10% (10% range)

P a g e | 13
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
4 to 20mA WIRING
Wiring Diagram: LBW-420-LEL with (1) –24 VDC
Power Supply
For this configuration, with the jumper J3 in the leftmost position
(which connects pins 2 & 3) power for the 4-20 mA circuit is
provided by the LBW-420-LEL. This circuit is shown below. The
power supply must supply all power for the LBW-420-LELplus the
4-20 mA circuit. Refer to the specifications page for the power
requirements for the LBW-420-LEL. The voltage drops across the
detector and the receiver together must not exceed the power supply
voltage. This circuit is shown in figure 1 below:
FIGURE 1

P a g e | 14
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Wiring Diagram: LBW-420-LEL with (2) –24 VDC
Power Supplies
In this configuration, with the jumper J3 in the rightmost position
(which connects pins 1 & 2), power for the LBW-420-LELis
supplied by the 24 VDC power supply #1 only. The power supply
must supply all power for the LBW-420-LEL. Refer to the
specifications page for the power requirements for the LBW-420-
LEL.The power for the 4-20 mA circuit is supplied by the 24 VDC
power supply #2. The 4-20 mA circuit is a simple series circuit that
includes the LBW detector, a power supply, and the receiving
device. It is recommended that a 24 VDC low-noise power supply
be used for this application, although power supplies providing a
minimum of 10 VDC to a maximum 30 VDC can be used. The
voltage drop across the detector and the receiver together must not
exceed the power supply voltage. This circuit is shown in Figure 2
below:
FIGURE 2

P a g e | 15
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
For the LBW-420-LEL, the maximum allowable resistance in the
receiving device must not exceed Rmax using this formula:
Rmax = 50 (Vs –7.5)
Where Vs is the supply voltage in volts DC for the 4-20 mA circuit.
For example, with a supply voltage of 24 VDC, the maximum
allowable resistance is 825 Ω.
INSTALLATION AND SETUP
Caution: Do not apply power to the detector until instructed to
do so.
The detector comes with four mounting feet, packaged in the
detector enclosure for shipment. Use the directions that accompany
the mounting feet for mounting the detector enclosure.
The detector should be mounted in a location where ammonia leaks
are most likely to occur, such as near valve groups, compressors,
and refrigeration coils. Be sure the detector is visible and easily
accessible. Avoid locating the detector where it might be damaged
during wash-down.
When power is applied to the detector, it will immediately go into
alarm status and the display will show an unusually large ammonia
concentration. This is normal. When the sensor warms to normal
operating temperature (usually about a minute) the detector will
return to a non-alarm status. However, you will need reset the relays
(see “Resetting the Relays”) as they are latched in the alarm
condition until a manual reset is initiated. For this reason, the
detector should be placed in service mode before applying
power to the detector to avoid unwanted alarm condition.

P a g e | 16
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
The detector is calibrated and programmed at the factory. To
program the detector for its specific installation, follow these steps
in the order given:
1. Open the detector enclosure and place the detector in service
mode by moving the service jumper to the “ON” position.
2. Apply power to the detector and allow the sensor to warm to
normal operating temperature (at normal operating temperature,
the display will read “0” and Alarm LED will be unlit).
3. Program the ammonia Alarm set point. See the next section on
programming the ammonia alarm set point.
4. Be sure the displayed ammonia concentration is below the
programmed alarm set point, return the detector to normal
operating mode by moving the service jumper to the “OFF”
position.
5. Test the detector to ensure it is operating correctly (but allow at
least 10 minutes after power is first applied to the detector
before testing). See the section on testing the detector.

P a g e | 17
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Remote Alarm Installation
Remote Alarm provides audible and visible alarms of the LBW-
420-LEL at a remote location. This wiring diagram shows the
connections from the LBW-420-LEL to the Remote Alarm. Power
for the Remote Alarm is derived from LBW-420-LEL TB7 on the
Front Panel Circuit Board. An alarm signal is derived from the
LBW-420-LEL enclosure-mounted circuit board. The Remote
Alarm device is pictured next to the wiring diagram

P a g e | 18
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
PROGRAMMING AND OPERATION
The LBW-420-LEL detector is easy to program and operate.
Follow the instructions in this section to:
Program the ammonia alarm set point
Set the 4 to 20mA range
Set the Service mode time out
Programming the Ammonia Alarm Set Point
The Alarm set point can be set from .1% to 9.9% in .1% increments.
1. Open the detector enclosure and move the service jumper to the
“ON” position.
2. Set the rotary selector switch to position “3”.
3. Press the “UP” or “DOWN” button until the desired set point
concentration in % is displayed.
4. Press and hold the “ENTER” button for at least 2 seconds. The
new set point is now programmed.
5. Return the rotary selector switch to the desired position.
6. Be sure the ammonia concentration reading is below the
alarm set point, then move the service jumper to the “OFF”
position and close the detector enclosure.
Resetting the Relays (for use only when the ammonia
concentration is below the alarm set point)
If the detector has gone into an alarm condition (at or above the
Ammonia Alarm Set point) the relays will activate and stay
activated until this manual reset procedure is completed.
1. Install the jumper on the jumper pins (labeled “SET1”) located
below the rotary selector switch on the front panel-mounted
circuit board.
2. Set the rotary selector switch to position “5”. The display will
indicate the current ammonia concentration in percentage.
3. Press the “ENTER” button for two seconds. The relays should
reset to their normal operating condition.

P a g e | 19
Rev. 2.1 7-7-2017
Copyright © 2017 by Cool Air Incorporated. All rights reserved.
Programming the 4-20 mA range
The ammonia level 4-20 mA signal can be scaled to one of three
ranges, either 0-1% (r.1), 0-2% (r.2), or 0-10% (r.3). To program
the 4-20 mA range, follow these steps:
1. Open the detector enclosure and move the service jumper
to the “ON” position.
2. Install the jumper on the jumper pins (labeled “SET1”)
located below the rotary switch on the front panel-mounted
circuit board.
3. Set the rotary selector switch to position “3”. The display
will indicate the current range, either “r.1 (0 to 1% range),
“r.2” (0 to 2% range), “or “r.3”(0 to 10% range).
4. Press the “UP” or “DOWN” button until the display
indicates the desired range.
5. Press and hold the “ENTER” button for at least 2 seconds.
The new range is now programmed.
6. Remove the jumper and return the rotary selector switch to
the desired position.
7. Move the service jumper to the “OFF” position and close
the detector enclosure.
Setting the Service Mode Timeout
If the service jumper is not returned to off, you can change how
long the detector stays in service mode before returning to normal
operating mode.
With the SET jumper on and the Rotary Switch in position 4 you
can use the up and down buttons to select either;
1.5d –After 15 minutes in the on position the detector will return to normal
mode.
3.0d –After 30 minutes in the on position the detector will return to normal
mode.
4.5d –After 45 minutes in the on position the detector will return to normal
mode.
6.0d –After 60 minutes in the on position the detector will return to normal
mode.
Once you have selected the desired service mode timeout you must
hold the ENTER button for two seconds before removing the SET 1
jumper or changing the rotary switch.