
South Bend, Indiana USA | networketi.com SNOW/ICE CONTROL INSTALLATION MANUAL | PART NO. 24782 REV C
6
INITIALIZATION SEQUENCE
Upon power up, the LCD-8 performs an initialization
sequence, allowing a user or technician to verify its
operation.
First, the interna 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 conguration 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 denes a “snow” event. For a precipitation
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 unless 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.
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.
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
condition 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 temperature 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).