Marley LLC+u User manual
LLC+uultrasonic water level control
INSTALLATION - OPERATION - MAINTENANCE
Z1079969 ISSUED 10/2018 READ AND UNDERSTAND THIS MANUAL PRIOR TO OPERATING OR SERVICING THIS PRODUCT.
user manual
2
contents
System Diagram..........................................................................................................4
Description ...................................................................................................................4
Programming................................................................................................................6
Operation......................................................................................................................9
Water Makeup Function............................................................................................9
HAND-OFF-AUTO Switch........................................................................................9
Troubleshooting........................................................................................................10
Field Wiring - Parts List ..........................................................................................11
This manual contains vital information for the proper installation
and operation of the LLC+u controls. Carefully read the manual be-
fore installation or operation and follow all instructions. Save this
manual for future reference.
Note
Indicates presence of a hazard which can cause severe personal
injury, death or substantial property damage if ignored.
Indicates special instructions on installation, operation or mainte-
nance which are important but not related to personal injury hazards.
Warning
Note
The following defined terms are used throughout this manual to
bring attention to the presence of hazards of various risk levels, or
to important information concerning the life of the product.
3
introduction
These instructions are intended to assure that field connections are completed
properly and the control system operates for the maximum time possible. Since
product warranty may depend on your actions, please read these instructions
thoroughly prior to operation.
If you have questions about the operation and/or maintenance of this control
system and you do not find the answers in this manual, please contact your
Marley sales representative.
Hazard of electrical shock or burn. Be sure to turn off power to the
panel before servicing. If working on equipment out of site of panel
disconnect, lockout using standard lockout procedure.
Safety First
The Marley control system uses UL listed components installed in accordance
with the National Electric Code. The location of the cooling tower and field
installation of the control system can affect the safety of those responsible
for installing, operating or maintaining the tower and controls. However,
since SPX Cooling Technologies does not control the tower location, or field
installation, we cannot be responsible for addressing safety issues that are
affected by these items.
The following safety issues should be addressed by those responsible
for installation, maintenance or repair of the tower and controls:
• Access to and from the control panel (including the customer supplied
main disconnect/branch circuit protection.)
• Proper grounding of electrical control circuits.
• Sizing and protection of branch circuits feeding the control panel.
• Qualification of persons who will install, maintain and service the electri-
cal equipment.
These are only some of the safety issues that may arise in the design and
installation process. Marley strongly recommends that you consult a safety
engineer to be sure that all safety considerations have been addressed.
Other safety issues are addressed in literature supplied with your tower. You
should closely review the literature prior to installing, maintaining or repairing
your tower.
Warning
Warning
4
description
The Liquid Level Control systems are used to accomplish
five different functions:
• Water Makeup • High Water Alarm
• Low Water Alarm • High Water Cutoff
• Low Water Cutoff
The most common application of a water level control
system is water makeup. The system regulates the amount
of water in the tower basin and keeps it within normal
operating levels. This makeup system is used to control
a remotely installed water solenoid valve. When the water
level drops below a prescribed, preset level, the solenoid
valve is energized by the control system to fill the basin
to its proper level.
LLC+u
Control Panel
with Display
Sensor
30'-0 Lead 4-20mA level signal
High and low cut-off dry contacts
High and low alarm dry contacts
MU powered with 120V
Ethernet
Solenoid
Pump
Pump
BMS
Stilling
Chamber
Basin Floor
6amp 120/1/60
Utility Supply
Junction
Box
Extension
if required
Display
SYSTEM DIAGRAM
LLC Components Optional Field Components—by others
High and low water alarms can be utilized to give warn-
ings associated with abnormal operating water levels. To
provide indication of these types of alerts, the control sys-
tem provides dry contacts to interface with various digital
control systems or can be connected to user supplied alarm
indicators to signal when corrective action is required.
Low-water cutoffs are commonly used to protect pumps
from operating without sufficient water. When used in
unattended operating environments, the low-water cutoff
is configured to shut the pump off, thus preventing costly
repairs. Dry contacts can be wired directly in series with
pilot duty controls or to digital control systems to initiate
the shutdown of protected equipment during low-water
situations.
5
description
Route incoming power cable from
the bottom of the enclosure up
into the top (line) side of the main
circuit breaker.
Circuit breaker powers a remote
solenoid.
H-O-A selector switch for makeup
solenoid circuit.
If a makeup solenoid circuit is
provided, connect the solenoid
wires here at points 4A and 2A.
This circuit provides 120 VAC
power for the solenoid.
Seal field-added conduit holes
with silicone or expanding foam to
create a vapor barrier to prevent
water vapor inside the enclosure.
4-20mA output signal
representing actual water level
for remote BMS monitoring.
Connect alarm and/or cutoff
control wiring to the grey terminal
points.
Ultrasonic sensor wiring.
Selector Switch Operation
HAND: position: Solenoid will energize. OFF: position: Solenoid is de-energized
AUTO: Solenoid will operate depending on water level in relation to water probe height.
6
programming
SCREEN LAYOUT
Red indicates the relay inside the control panel has been energized.
LEVEL IN INCHES–actual water level in the cold water basin
GOTO SETUP–use to program sensor heights and setpoint levels.
Default password is 1492
INFO–use to see programmed levels
Requires field programming
1. Measure and program the distance between sensor and water basin floor
2 Program the water level setpoints
3. Operate WATER MAKE UP selector switch to operate
solenoid valve circuit
The WATER MAKE UP selector switch controls the makeup
solenoid circuit
HAND position–manually energizes remote makeup solenoid
OFF position–no power to remote makeup solenoid
AUTO position–ultrasonic makeup water level sensor activated
Note
7
programming
Feeder breaker powers the
remote solenoid.
Main circuit breaker powers the
control panel
PROGRAMMING STEPS
Power ON the control panel circuits by
moving the switches on the two circuit
breakers to the up position.
Measure the distance from the bottom of
the ultrasonic sensor to the basin floor.
Access the program by pressing
GOTO SETUP
Press the light blue screen cell under
ENTER PASSWORD bringing up a
yellow keypad then enter password 1492
(factory default password) and press ENT
to access the setup screens.
BOTTOM OF SENSOR
TO BASIN FLOOR
1"
CIRCUIT PROTECTION
➠
8
programming
Press the light blue screen cell to right of
SENSOR HEIGHT to bring up a yellow
keypad then enter the sensor height in
inches. Sensor height is from bottom of
the sensor to basin floor (or bottom of
PVC tubing in case of an external stilling
chamber.
Press the NEXT button to enter additional
programming screens.
On each screen, enter the water level
setpoint values by pressing the light blue
cell and entering a value on the yellow
keypad then press ENT to save.
Recommended levels are unique for every
cooling tower and are available from your
Marley sales representative.
When finished press GO TO MAIN to
return to main screen.
On the main screen are view actual water level and relay actions. The reac-
tion time is purposely slow to allow time for the system to react and refresh
the screens.
9
operation
Operation
The LLC+u water level control system consists of an ultrasonic sensor placed
to measure the water level in the cold water basin. The senor is typically located
inside the cooling tower or on some cooling towers in an external chamber. A
PLC with HMI touch screen is used to program water level heights and offers
a visual indication of the water level. Internal relays with form "C" contacts are
used as switches, one for each water setpoint.
Programming is accomplished in the field based on recommended cooling
tower water level heights. Contact your Marley sales representative for recom-
mended setpoint levels. The sensor is programmed with a height from sensor
to bottom of the basin floor. Individual setpoint levels are programmed for high
cutoff, high alarm, makeup, low alarm and low cut off.
Alarm set point may be used to complete a remote BMS alarm circuit. Cut off
set point may be used to shut of a circulating pump.
A 4-20mA output is provided for BMS remote monitoring of water level
Water Makeup Function
The circuitry for water makeup in the LLC+u control panel provides an inde-
pendent circuit breaker for direct connection to a 110-120VAC water solenoid
valve. This added feature allows customer installation without having to provide
an additional power circuit to energize the solenoid. The solenoid is connected
to terminals 2A and 4A as represented on the control’s specific wiring diagram.
Purpose and Function of the HAND-OFF-AUTO Switch
Located on the right side of the control’s enclosure is a
HAND-OFF-AUTO switch. This switch is used primarily
at cooling tower startup and in maintenance procedures
where the tower basin is empty or has been drained. When
the tower’s basin needs to be manually filled, the switch is
placed in the HAND position. This selection bypasses the
probe assembly’s feedback and directly energizes the solenoid
valve connected to the water supply. Once the cooling tower basin is filled,
the switch is placed in the AUTO position to allow the adjusted ultrasonic
sensor to monitor and sustain the proper operating level. Placing the switch
in the OFF position completely interrupts any monitoring or fill action normally
provided by the LLC+u control panel. Normal tower operation depends upon
the HAND-OFF-AUTO switch being positioned in the AUTO mode at all times.
10
troubleshooting
The control panel has been factory tested before shipment and most issues
lie outside of the control panel e.g. proper field wiring connections to the
control panel.
In an effort to troubleshoot the system, please check the following:
• The two circuit breakers must be energized with operating handles in
the up position
• The unit requires programming in the field. See programming instruc-
tions in this manual. The ultrasonic sensor head does not require any
field programming.
• Check water make up selector switch position.
• Confirm the two sensor wires are oriented and correctly connected at
terminal points in the control panel assuring the terminal connection
does not land on the insulation of the sensor wire. Strip back just enough
wire insulation so you can see some copper wire exposed assuring a
metal-to-metal connection.
• The sensor wire is a four wire plus shielded cord. The red and black wires
connect to terminal points 24 and 13. The shield connects to ground.
Always refer to the as-built wiring diagram on the inside door panel for
current connection points. Tape back the white and green wires that are
not used.
• If sensor wires were extended in the field, check to make sure the exten-
sion wires were numbered correctly and connections secure.
• Assure no external power wiring from other devices run in parallel with the
sensor wiring. Follow best practice wiring for power and instrumentation
wiring placements.
Checking the power circuit for the makeup solenoid
• Rotate the WATER MAKE UP selector switch to the HAND position. The
solenoid should energize allowing makeup water to flow into the cooling
loop. Inside the control panel is a single-pole circuit breaker, which must be
in the ON position to power the circuit.
11
field wiring - parts list
Part Number Description
2599336 120 VAC Ultrasonic LLC+u Control Panel
2588880 DL10 Ultrasonic sensor only with 30 ft cable (no junction box or fittings)
2586100 DL10 Ultrasonic sensor with 30 ft cable, junction box and 3" union slip fitting for round PVC stilling
chamber located external to the cooling tower
2599330 DL10 Ultrasonic sensor with 30 ft cable, junction box and 3" threaded fitting for square metal stilling
chamber located internal to the cooling tower
2586086 100 ft 4-18 AWG PVC cable
2586087 150 ft 4-18 AWG PVC cable
2586088 200 ft 4-18 AWG PVC cable
120 VAC LINE VOLTAGE
2 POLE
6AMP
HOT
GND
NEUTRAL
Wiring diagram is typical. Refer to wiring diagram on inside of the enclosure door for actual as-built wiring
diagram, which may include project specific options.
Wire 120 VAC incoming voltage supply to line side (top) of the main 2 pole circuit breaker CB1 and CB2
Wire 120 VAC remote makeup solenoid to terminal points 2A and 4A
Wire alarm and cutoff circuits to terminal points 5 through 22 as needed
Wire ultrasonic sensor:
• Red to terminal point +24
• Black to terminal point 13
• Shield to GND (Do not ground shield any other location, only at the LLC+u control panel)
• The white and green sensor wires are not used.
Wire 4-20mA output signal representing the water level in basin from points 4-20+ and 4-20- to customers BMS system.
Z1079969 | ISSUED 10/2018
©2018 SPX COOLING TECHNOLOGIES | ALL RIGHTS RESERVED
In the interest of technological progress, all products are subject to design
and/or material change without notice.
LLC+u water level control
USER MANUAL
SPX COOLING TECHNOLOGIES, INC.
7401 WEST 129 STREET
OVERLAND PARK, KS 66213 USA
spxcooling.com
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