Overview
The CDP-2 Snow Sensor Control/Display Panel is used in conjunction with a DS-2B or DS-5 Rain/Snow
Sensor Controller. The sensor is typically mounted on a roof, near a gutter, or in a similarly difficult
location to reach. The CDP-2 provides a method of remotely monitoring and controlling the attached
sensor. The user may monitor both the operating mode and the activation state of the sensor. The user
may also set the sensor to prohibit automatic operation, to automatically operate, or to manually operate
one snow melting cycle, then return to automatic operation. The CDP-2 derives its power from the snow
sensor and requires no batteries or AC power. With an operating temperature range of -40°C to +85°C
the CDP-2 is designed for use either indoors or outdoors with proper protection from the elements.
Installing the CDP-2 Control/Display Panel
Installation requires a CS-1 Remote Control/Monitor Pigtail for the snow sensor and an appropriate 5-
conductor cable for installation between the snow sensor and the CDP-2. The cable conductors must
be tinned, stranded, minimum 22 AWG copper and overall shielding is required. An appropriate
selection is Belden®9941 or equiv. The CDP-2 can be installed as much as 500 feet away from the
snow sensor if proper cable is used. Remove all power to the snow sensor, open its cover, and install
the CS-1 pigtail. Install the 5-conductor cable between the sensor and the CDP-2 enclosure. Ground
the “drain” wire on one end only and terminate the cable leads to the CS-1 following the table below:
CS-1 Color Function Your Color CDP-2 TB-1
Black Manual On 5
White Return 6
Green Standby/Reset 7
Orange Deice On Mon 8
Red Deice On Mon 9
The CDP-2 may be installed in a conventional single or multi gang standard electrical enclosure. If
installed in a multi gang enclosure next to high voltage equipment the CDP-2 and its interconnecting
cable must be isolated from high voltage wires and devices. Consult local electrical codes to determine
the isolation methods required. Remove 2 in. (50mm) of outer insulation and shield from the 5-conductor
cable. Remove ¼ in. (6mm) of insulation from the individual inner conductors. Following the above table
press the clamp button on the terminal block, insert the bare lead into the clamp hole, then release.
The CDP-2 faceplate can be grounded to reduce the chances of damage due to static shock. This can
be an important consideration when operating in a very dry environment in the winter. Remove 1 in.
(25mm) of insulation from the green EGND lead and connect this lead to an electrical ground lead using
a wire nut or equivalent.
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Install the CDP-2 into the electrical enclosure using the two screws provided. The screws are compatible
with both metallic and non-metallic enclosures. Once installation is complete a “modular” electrical cover
plate can be installed. Compatible types include the Leviton®Decora®and Hubbell®Styleline series.
External Control/Monitor Operation
The CDP-2 indicators show the current setting of the manual override switch for the attached snow
sensor, either MANUAL ON, AUTOMATIC, or STANDBY. The sensor override switch will also override
any current CDP-2 commands. Whenever the sensor’s switch overrides the CDP-2’s setting, then
returns to AUTOMATIC mode, the CDP-2 will also return to AUTOMATIC mode. The sensor override
switch should be left in the center AUTOMATIC position to allow the CDP-2 to control the system.
The CDP-2 provides three pushbutton switches; STANDBY, AUTOMATIC, and MANUAL ON. The
respective LED indicators for each control reflect the current operating mode of the snow sensor. Note
that, to save energy, the LED indicators
blink periodically rather than remaining
steadily illuminated. Pressing STANDBY
will set the connected snow sensor to
ignore snow fall and prohibit automatic
operation of an attached snow melt system.
This function can be used to save energy if
automatic snow melting is not critical.
Pressing AUTOMATIC will set the
connected snow sensor to automatically
activate and control an attached snow melt
system when snow is detected. Note that,
if power is lost, the CDP-2 will always
repower into AUTOMATIC mode.
A “Delay Off” drying cycle time is configured
on the snow sensor with a time delay of 30-
90 minutes. It begins once snow stops
falling and allows the heated surface to
more thoroughly dry. For example, if the
cycle is set for 30 minutes and snow falls for
2 hours the snow sensor will operate the
snow melt system for 2 hours, 30 minutes. Switching the sensor override switch to the MANUAL ON
position will cause the sensor to close its relay, illuminate the CDP-2 MANUAL ON and DEICE ON
indicators, and activate the snow melt system continuously. Pressing the MANUAL ON button on the
CDP-2 will not trigger the sensor to run continuously but will initiate one drying cycle. This mode can be
used to test the system or clear any remaining unmelted snow. This function allows the user to run a
cycle without having to remember to shut the system back off. The sensor will initiate one drying cycle
and revert to automatic mode, ready for detection. The MANUAL ON mode can be activated directly
from either AUTOMATIC or STANDBY mode. The user may clear the drying cycle by pressing
STANDBY. Note that a properly working unit will not show a MANUAL ON indication during this
cycle but will show AUTOMATIC with a DEICE ON indicator.
The DEICE ON indicator shows whether or not the attached snow sensor has been activated and the
snow melting system is operating.
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General Safety Instructions
1. THIS UNIT SHOULD BE INSTALLED BY QUALIFIED PERSONNEL ONLY!
2. To avoid shock hazard do not open the front cover of the attached rain/snow sensor
controller with power connected to the controller or any controlled equipment.
3. Always open any circuit breakers and remove power from any high voltage electrical circuits
installed in close proximity to or sharing an enclosure with the CDP-2 prior to removing the
enclosure cover plate.
CDP-2
Deice On
Snow Sensor
Control/Display Panel
Standby
Automatic
Manual On
SYSTEMS
AUTOMATED
ENGINEERING
