WarmlyYours SCV-DUAL - Manual (Page 5)

Snow Switch ® Model LCD–8 Aerial Snow Controller, 100 – 240 VAC
24782 Rev. A 03/13 (800) 234-4239 http://www.networketi.com 4 of 14 Environmental Technology, Inc.
green LED
Ambient Air
Temperature
Sensor
yellow LED
Figure 2. LCD-8 LEDs
Figure 1. LCD-8
General
LCD-8 Overview
The Snow Switch ® Model LCD–8 (Figure 1) is a configurable aerial snow melt-
ing 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 available as a model which operates from either an
automatic selecting 100VAC – 240VAC or as a model which operates from 24VAC.
These two voltage options combine with the configurable hold-on time and tem-
perature set point to meet the need of a wide number of applications using just two
part numbers.
It controls heater loads up to 16 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-Test™ 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.
• 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.