ETI SNOW SWITCH LCD-8 User manual

PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
SAFETY INFORMATION AND WARNING SUMMARY
Electrical Shock / Fire Hazard
Even when the snow melting elements are
disconnected, as long as the circuit breaker is on and
power is running to the unit, voltage is still being
applied to the system’s yellow leads. Therefore,
never touch the ends of the yellow leads or let the
two leads touch each other. Do not let the two yellow
leads contact any component inside the unit.
Any installation involving electric heater wiring must
be grounded to earth to protect against shock and
fire hazard. Suitable ground fault detection and
interrupting systems must be in use at all times to
reduce shock and fire hazard and to protect
equipment.
Electric wiring to heating elements must be installed
in accordance with National Electrical Code (NEC)
requirements and all other local and applicable
electrical codes and any third party standards.
Follow the installation instructions contained herein
and those provided by the heater manufacturer.
Use a GFEP (Ground Fault Equipment Protection)
circuit breaker on each branch circuit connected to
the ice melting system. Clearly label each circuit
breaker with its function. This is vitally important
when there is more than a single point of disconnect.
Size the circuit breaker in accordance with the size of
the expected load. The maximum current load for
the LCD-8 is 3 amp resistive for 24 VAC.
Electrical Shock / Fire Hazard (CONT.)
Abnormal Odor or Smoke
In the event of smoke or a burning or abnormal odor,
immediately interrupt power to the unit by
unplugging the unit or by turning off the circuit
breaker protecting the unit.
Make all electrical connections in compliance with the National
Electrical Code (NFPA 70) and local electrical code. If you have
questions concerning the installation or application, contact
Customer Service.
This product is intended for use in residential or light
commercial applications.
Make certain that the heater shield is properly
grounded. Failure to do so may result in damage to
the equipment or fire.
Following installation and prior to beginning system
operation, refer to and perform the Post-Installation
Tests (page 12) described in this manual.
Additional Information
More information is made available regularly
through our website, www.networketi.com.
Please visit us on-line for Data Sheets, Manuals,
White Papers, technical articles, and more. The most
current and up to date version of this and every other
manual for our products can be found in Acrobat
(PDF) format to view on-line or to print.
This is to assist you in installing and using our
products to the best effect possible. If you have any
comments about this or any other product from ETI.

2
LCD-8 24VAC OVERVIEW
general
PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
The Snow Switch® Model LCD–8 (Figure 1) is a configurable
aerial snow melting system controller which makes automatic
snow melting a cost-effective alterna- tive in even the smallest
applications. Heaters operate at temperatures below the
LCD-8’s configurable set point, 38°F (3.3°C) default, only when
required. The adjust- able hold-on period, 3 hours default,
continues heater operation after snow stops to ensure complete
melting. The LCD–8 controller includes an internal magnetic
reed switch used for manual heater cycling and configuring the
controller’s operational temperature set point and hold-on time.
The LCD–8 controller is a model which operates from 24VAC
with the configu- rable hold-on time and temperature set point.
It controls heater loads up to 3 amps resistive or 3 amps
inductive. The operating temperature range extends from –40°F
to 140°F (–40°C to 60°C). The redesigned, patent pending,
rugged polycarbonate enclosure provides excellent protection
at temperature extremes, while allowing snow to shed to
prevent iglooing over the moisture sensor.
The internal magnetic reed switch allows for both configuration
and manual heater operation without the need for external
switches—which are susceptible to damage—or the need to open
the enclosure.
Verifying system functionality after installation or when
troubleshooting used to require spray circuit cooler or ice for
controller activation. The Sno-TestTM feature eliminates this
need by performing a self-test after power application and
operating heaters in a unique pattern for a few seconds.
Reading the test results takes only an AC voltmeter or clamp-on
ammeter.
A configurable snow sensor with two light-emitting diode (LED)
indicator lamps (Figure 2), the LCD-8 features a hold-on timer
which allows its system to operate to a drier surface after
melting snow.
The hold-on timer can be configured for off, 1 hour, 3 hours
or 5 hours. The operating temperature can be configured
for none (precipitation sensor), 36°F, 38°F or 40°F.
The low-temperature lockout (17°F), which disengages unit
operation, can be enabled or not.
Default configuration: 38°F operating temperature; 3 hour
hold-on; no lockout. The LCD-8 uses an internal magnetic
switch. The user swipes a magnet externally across this
switch to start a hold-on cycle or to terminate a running
hold-on cycle. This switch may also be used to reconfigure
the unit, or to view the current configuration.
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The green LED, ordinarily on steady, blinks to indicate a
concern with the unit. This LED is also used in the LCD-8’s
configuration process.
The yellow LED indicator is lit whenever the output relay is
powered (“on”).
There is an initialization period where the heaters are
tested.
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FIGURE 1
LCD-8 24VAC
Green LED
Ambient Air
Temperature
Sensor
Yellow LED
FIGURE 2
LCD-8 LED LIGHTS

3PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
UNPACKING THE LCD-8 INSTALLATION
Immediately upon receipt, inspect the container and packing
material for any noticeable damage. Unpack the unit, taking
care not to damage the packing materi- als. Confirm all
components noted in “Packing List” above are included. Save
the shipping container and related materials until normal
operation has been estab- lished. If the unit must be returned,
take care to ensure that it is repackaged as it was received.
As soon as the unit arrives at your facility, inspect it for
mechanical damage. If any of the following problems is found,
contact Environmental Technology, Inc., Customer Service
immediately:
RETURNS AND REPLACEMENT PART PURCHASES
Equipment cannot be returned for credit once
it has been installed.
Environmental Technology, Inc. will repair or replace faulty
equipment under warranty.
Prior to removal of equipment for warranty return, please
contact Environmental Technology, Inc. Technical Support at
[phone] for troubleshooting assistance.
Before returning a unit to Environmental Technology, Inc.,
obtain a Return Merchandise Authorization (RMA) from our
Customer Service Department at:
TOLL FREE: [phone]
LOCAL: [phone]
MON - FRI
8:00AM - 5:00PM (EST)
If possible, use the original container and packing materials
when packing the unit for shipment. It is important to mark the
Return Merchandise Authorization clearly on the outside of the
shipping container so that it may be correctly processed upon
receipt at Environmental Technology.
For more information about replacement parts or for a
replacement Data Sheet or Manual, please visit
http://www.networketi.com/.
Contents in complete or incorrect;
Internal or external mechanical damage; or
Defective operation.
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With user-supplied hardware, mount the LCD-8 securely in an
upright position (sensor grid at top; see Figure 3) in a clear and
open area typical of the area to be melted, either above the
roof line or removed from the building and exposed to, rather
than protected from, falling snow.
The LCD-8 also should be positioned at a height above ground
that reduces, eliminates or discourages damage caused by
animals or vandals.
AVOID overhead trees, shrubs, wires, eaves, etc., and
falling or blowing debris.
AVOID vehicle and foot traffic. Do not create a safety
hazard.
AVOID exposure to artificial heat sources and excessive
shock and vibration.
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FIGURE 3
LCD-8 24VAC INSTALLATION
Ø 4.60”
Ø 117mm
6.35”
161mm
0.50”
13mm
0.75”
29mm
Sensor grid
Be certain sensor grid is in a
clear and open area
identical to that requiring
melting and exposed to
falling snow.
Mount rigidly in an upright position,
as shown, at a height above ground
as necessary to discourage animal
damage and vandalsim.
Ambient air temperature sensor
Cool this area per instructions when testing
Weatherproof conduit body or junction
box supplied by customer.
Make all threaded joints weathertight.
Insulate splices with wire nuts.
Designed to be mounted using PVC
conduit using either 3/4” inserted into the
flange (0.82”/21mm ID) or, with a coupler,
1” mounted around the flange
(1.32”/34mm OD).
Consider PVC adaptor if using metal
conduit.

4
Install in accordance with the requirements of all applicable electrical and building codes and
regulations. Ensure that all conduit and cable terminations are watertight.
NEC Article 426.28 requires Equipment Ground Fault Protection (GFEP) for Ice and Snow Melting
Equipment. This functionality is not provided as part of this controller and shall be provided as part of
the overall system.
PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
Wiring:External Contactor
BLKL1
YEL
WHT
L2/N
24 VAC
50/60 Hz
K1
Inductive load, up to 3 amps
(Contactor, Pump Motor,
Motorized Valve, etc.)
Solenoid Valve
YEL
Wiring:Dry Contact
BLKL1
WHT
YEL
YEL
L2/N
16 Amp Resistive
3 Amps Inductive
24 VAC
50/60 Hz Dry Contacts
BLK3
1
YEL
WHT
2
24 VAC
50/60 Hz
Inductive load, up to 3 amps
(Contactor, Pump Motor,
Motorized Valve, etc.)
Solenoid Valve
YEL
24V used with
APS Models
BLK26
25
YEL
WHT
24
24 VAC
50/60 Hz
Inductive load, up to 3 amps
(Contactor, Pump Motor,
Motorized Valve, etc.)
Solenoid Valve
YEL
24V used with
EUR– 5A
INITIALIZATION SEQUENCE
operation
Upon power up, the LCD-8 performs an initialization sequence,
allowing a user or technician to verify its operation.
First, the external relay energizes for ten seconds. Next, the relay
powers off and the cup heaters energize for ten seconds. Finally,
both are off for another ten seconds. During this time, the green
LED blinks slowly—one (1) second on, one (1) second off. Normal
operation follows.
When energized, the controller’s green LED is on continuously.
During an alarm condition, the green LED blinks quickly,
alternating between on and off twice a second. Exceptions are
when the green LED conveys information during the configu-
ration process or when the unit is in an automated testing
device.
When the system detects moisture and the ambient
temperature is below the operating temperature, if there is one,
this defines a “snow” event. For a precipita- tion sensor
(operating temperature off), moisture is detected at any
temperature: this could be snow or rain.
FOUR STATES OF LCD-8 CONTROLLED SYSTEM
The system can be in one of four states, three with lockout
disabled or one in lockout enabled:
IDLE: the LCD-8 monitors during conditions lacking
moisture and/or cold air temperature
CALL FOR HEAT: the LCD-8’s sensors recognize snow or ice
as moisture
HOLDING: the LCD-8 continues system operation for
hold-on duration un- less snow begins again; when hold-on
time is over or parameter is set to zero (0), systems returns to
Idle state
LOCKOUT ENABLED: low-temperature lockout, where
temperature is too cold for system to operate effectively and
energy is conserved The heater is on during a snow event or
within its holding state.
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5PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
INITIATING HOLD-ON STATE
The user can also swipe the magnet to start a hold-on cycle or
to terminate a hold-on cycle. If a manual cycle is started, it
operates for the normal hold-on duration (note: if the hold-on
time is set to 0, operation lasts one hour).
––
However, if the ambient temperature is above 50°F when the
cycle starts, the cycle duration is ten (10 ) minutes. If the
temperature rises above 50°F during the cycle, operation
truncates to 10 minutes. This 10-minute constraint is only for
manually-triggered hold-on cycles; a cycle resulting from snow
proceeds for the full duration. Note: this does not apply to a
precipitation sensor.
ALARMS
When the LCD-8 operates normally, its green LED is lit
continuously. Under an alarm condition, this LED will flash
rapidly—on and off twice a second. The alarm may or may not
inhibit operation, depending on circumstances.
Three possible conditions exist which initiate an alarm:
GREEN LED PULSE PATTERN
Prior to learning how to change the configuration of the LCD–8,
it is first nec- essary to understand how the device
communicates with the user; see Table 1. As there is no display
on the unit, the only means of communicating with the device is
to carefully observe the pulse pattern of the green LED.
The bad thermistor alarms will clear if the thermistor repairs
itself. The cor- rupted configuration alarm will clear if the unit is
reconfigured: in that case the user is advised to cycle power,
confirming reconfiguration.
SPECIAL CASE: HOLD-ON TIME IS 0
For the special case that only occurs with a manual swipe when
the hold-on time is set to zero (0), the heater operates for at
least one hour, even if there is a snow condition. In terms of a
strict state description in this one case, a snow condi- tion does
not cause the system to enter the snow state, but rather to stay
in the hold-on state. If the snow remains after the one hour, the
heater remains energized.
In the “enabled” Lockout state, the heater is not on. When snow
is detected, the system enters the Snow state if the ambient air
temperature is above 17°F, but it enters the Lockout state
instead if the temperature is below 17°F. Additionally, this
Lockout state is entered if the temperature falls below 17°F
during an automatic hold-on cycle. If the temperature rises
above 17°F in the Lockout state but with no moisture detected
(not snowing), the hold-on timer is restarted. In the Lockout
state, the heater is not on.
If in the Idle state and the temperature is below 17°F when a
magnet swipes the magnetic switch, the system initiates its
manual cycle as usual. If the tempera- ture falls below 17°F
during the cycle, it is ignored. If the unit is in the Lockout state
and the user swipes the magnetic switch, the temperature
reading is ignored. This will be maintained until the end of the
snow event (that is, until a return to the Idle state).
The override ends when the heaters turn off. However, if a
manual cycle is initiated while when the environment is frigid,
and then snow starts, the heaters remain energized until the
snow stops and for the hold-on time thereafter.
Note: Avoid selecting both low-temperature lockout and a
hold-on time of zero (0) hours, as the heaters may not energize.
BAD CUP THERMISTOR:
If the cup thermistor is bad, the unit will not do automatic
snow melting. The rationale is that we can’t turn on the cup
heater without risking damage to the unit; and if snow or
freezing rain falls with the cup cold, it may stay there for
weeks, and the unit would never shut off. The manual
hold-on cycle will work.
BAD AMBIENT THERMISTOR:
If the ambient thermistor is bad, the unit will operate
normally if it is configured as a precipitation sensor; if it is
configured as a snow sensor, it will not do automatic snow
melting. The manual hold-on cycle will work.
CORRUPTED CONFIGURATION.
If the configuration is corrupted, the unit will operate under
its default configuration.
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*When the Temperature Set-Point feature is configured to be in the “OFF” setting, the LCD–8 senses moisture
only and activates the heaters regardless of temperature.
Hold-On Time
(in hours)
0 Hours
(1 Pulse)
1 Hour
(2 Pulses)
3 Hours
(3 Pulses)
5 Hours
(4 Pulses)
Temperature
Set Point (in °F)
OFF*
(1 Pulse)
36°F (2.22°C)
(2 Pulses)
38°F (3.33°C)
(3 Pulses)
40°F (4.44°C)
(4 Pulses)
Low Temperature
Lock-Out
OFF
(1 Pulse)
ON
(2 Pulses)
TABLE 1
LCD–8 CONFIGURATION OPTIONS AND GREEN
LED PULSE PATTERN

6PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
LCD-8 MAGNETIC REED SWITCH
The LCD-8 uses an internal magnetic reed switch (Figure 4),
where the user swipes a magnet (Figure 5) externally across this
switch (Figure 6) to start a hold-on cycle or to terminate a
running hold-on cycle. The magnetic switch determines
whether the user’s action “swipes” or “holds” the magnet
during LCD-8 configuration.
Magnetic Switch
(inside unit)
FIGURE 4
MAGNETIC REED SWITCH
(internal)
Magnet
FIGURE 5
MAGNET
(external)
FIGURE 6
Positioning (left) and swiping (right) external Magnet over
internal Magnetic Switch

7PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
HOLD-ON TIME
Hold-on time refers to the number of hours that the heaters will
continue to operate once the unit no longer detects
precipitation. Hold-on time ensures that not only is all the snow
melted from the protected surface, but also that the system
continues to dry and evaporate the surface without refreezing.
The factory default hold-on time setting is 3 hours.
TEMPERATURE SET-POINT
The temperature set-point refers to the temperature at which
the LCD-8 activates the heaters given the presence of moisture.
When set to its default, “Off,” the controller activates the
heaters based only on the presence of moisture at any
temperature. The factory default temperature set point is 38°F
(3.33°C).
LOW TEMPERATURE LOCK-OUT
The low temperature lock-out function disables unit operation
in temperatures less than 17°F (–8.33°C) in those climates or
during those seasons where it is simply too cold to make
operation practical. The factory default low temperature
lock-out setting is Off, meaning that the unit will try to activate
the heaters regard- less of ambient temperature.
SETTING THE CONFIGURATION
FIELD 1: HOLD-ON TIME
1: off
2: 1 hour
3: 3 hours*
4: 5 hours
VALUES
FIELD 2: OPERATING TEMPERATURE
VALUES 1: none
(precipitation sensor)
2: 36°F / 2.2°C
3: 38°F / 3.3°C*
4: 40°F / 4.4°C
FIELD 3: LOW TEMPERATURE LOCKOUT
VALUES 1: disabled*
2: enabled
There are three fields available for configuration. Each has
several numerical values possible, as follows:
* Default values
LCD-8 CONFIGURATION
The user is able to configure three operating parameters on the
Snow Switch Model LCD–8.
These are:
The definitions of each of these parameters, as well as how to
determine their current setting and how to change those
settings, will be explained in this section of the manual.
The hold-on time in hours;
The temperature setpoint in degrees Fahrenheit; and
Low temperature lock-out operation.
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•
2 second pause
4 second pause; to top
2 second pause
3 hour hold-on
38°F / 3.3°C
Low temperature
lockout disabled
FIGURE 7
LED response, default configuration

8PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
TO SAVE THE NEW VALUE
After changing parameters, hold the magnet over the magnetic
switch for 3 seconds. The green LED turns off then flashes a
brief message (3 short pulses and a long pulse), and return to
normal mode. This can be done even if the parameters have
not been changed.
TO ABANDON THE PROCESS WITH NO CHANGES
Allow the LCD-8 to sit for two (2) minutes. The unit will flash the
green LED quickly for 2 seconds and return to normal
operation, displaying a steady green LED. This can be done at
any time in the process.
NOTE: changes to the operating temperature or the state of
the low- temperature lockout take effect immediately.
Changing the hold-on time does not affect any active hold-on
cycles; new values will be used the next time a hold-on cycle
initiates.
POST–INSTALLATION LCD-8 TEST
Most problems result from installation errors. Before testing,
verify that unit is prop- erly installed.
Connect power to snow melting system. Wait 15 seconds;
system should not actuate.
Using ice water or other cooling agent, cool ambient air
temperature sensor to below 38°F (3.3oC); system should
not actuate. Apply moisture to moisture sensing grid.
System should actuate in less than 15 seconds.
Dry moisture sensing grid. Disconnect power to snow
melting system. Wait 1 minute, then reconnect power. If
system actuates, ensure sensing grid is dry and ambient air
temperature is above 38°F (3.3°C), then repeat this step.
1.
2.
3.
TO ENTER THE CONFIGURATION PROCESS
The unit will flash the values of the three Field parameters in
order, repeatedly. The pattern begins with:
The four (4) second gap helps the user identify Field 1, the
starting point of the sequence, even after the sequences of
pulses have repeated several times. The LCD-8’s default
configuration is represented in Figure 6, above.
After changing the parameters of any field, the LCD-8 returns
to the display mode.
Hold the magnet to the switch for 3 seconds
The green LED will go off
Remove the magnet
Process begins
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TO CHANGE A FIELD’S PARAMETERS
Hold the magnet to the switch during the pause after that field.
The green LED turns and remains on until the magnet is
removed. That sets the value to 1. Positioning the magnet on
again, the LED turns on, then remove the magnet: that sets that
value to 2. Continue in this fashion.
There are two (2) seconds between swipes. After 2 seconds, the
LCD-8 main- tains the entered value and returns to display
mode. If a value exceeds parameters, the green LED flickers
briefly and returns to displaying the previous values.
Note: if the magnet is held for 3 seconds during the process of
setting a value (having been released at least once), the green
LED flickers briefly and restarts the display process.
Field 1’s green LED pulses
2 seconds between Field 1 and Field 2
Field 2’s green LED pulses
2 seconds between Field 2 and Field 3
Field 3’s LED pulses
4 seconds between Field 3 and returning to Field 1;
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9PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
SPECIFICATIONS
GENERAL
Area of use Nonhazardous locations
ENCLOSURE
Protection
Cover attachment Polycarbonate with machine screws
Entries 1 x 3/4" entry (bottom)
Material Polycarbonate
Mounting Pole mount
Dimensions 4.6" (W) x 6.1" (H) / 117mm (W) x 155mm (H)
CONTROL
Supply voltage ETI PN 24781: 24VAC; 50/60 Hz
Load 3 amp maximum inductive
3 amp maximum resistive
Heater Hold-On timer 0, 1, 3 (default) or 5 hours; configured by magnetic reed switch
Set point temperature Off (moisture only), 36°F, 38°F (default), 38°F;
configured by magnetic reed switch
INTERFACE
Status indicators SUPPLY (green):Power on; will flash while in configuration mode
HEAT (yellow):Heating cycle in progress
WIRE AND CABLE RATINGS
Power cable Size for heater load (16 amps maximum)
Heater cable Size for maximum heater load
ENVIRONMENTAL
Operating temperature –40°F to 104°F (–40°C to 40°C)
Storage temperature −67°F to 167°F (−55°C to 75°C)
ORDERING INFORMATION
Order Number Description
24781 LCD–8, 24VAC
18703 Red Wire Nuts (QTY 4)
24861 LCD–8 Manual (QTY 1)

10 PART NO. 24861 REV A.0INSTALLATION AND OPERATION MANUAL |
LIMITED WARRANTY
ETI’s two year limited warranty covering defects in
workmanship and materials applies. Contact Customer Service
for complete warranty information.
DISCLAIMER
ETI makes no representations or warranties, either expressed
or implied, with respect to the contents of this publication or
the products that it describes, and specifically disclaims any
implied warranties of merchantability or fitness for any
particular purpose.
ETI reserves the right to revise this publication, and to make
changes and improvements to the products described in this
publication, without the obligation of ETI to notify any person
or organization of such revisions, changes or improvements.
Copyright © 2020 ETI. All rights reserved.