Ds−2c, Setting the configuration switches and adjustments – Ouellet DS-2C User Manual

Page 6

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NEUTRAL BUS BAR

C

B1

BROWN

BLUE

YELLOW

YELLOW

LOAD

LOAD CENTER

C

B2

DS−2C

POWER SUPPLY

120VAC In, 240VAC Load, Separate Feed

CB

BROWN

BLUE

YELLOW

YELLOW

LOAD

LOAD CENTER

DS−2C

POWER SUPPLY

240VAC In, Dry Contact for Boiler/Circulation Pump

These are just some of the possible wiring schemes that can be used to connect the DS-2C to your load for

control. Remember, these are only suggestions. You should always consult a qualified

electrician or inspector to assure conformance with applicable local and national

electrical codes!

6

Setting the Configuration Switches and Adjustments

The following paragraphs and table outline the operating modes for the DS-2C and

explain the functions of the adjustments. Trigger temp (TT) is adjustable from

34°F-44°F (1°C-6°C) using the TRIG TEMP control. When ambient air

temperature (AT) is below this setting precipitation is assumed to be snow. When

above this setting, precipitation is assumed to be rain.

The DEL configuration switch activates the Delay-Off drying cycle timer on the DS-

2C. The timer allows the DS-2C to continue to operate and dry the heated surface through evaporation

once precipitation has stopped. The drying cycle reduces the chance of

moisture left behind refreezing into ice. This timer is restarted by each

sensor trigger. Therefore, the DS-2C will continue to operate as long as it is

triggered, then for the Delay-Off period once the trigger clears. All "sensor"

modes (DEL off) provide a 2 minute Delay-Off time. When in "controller"

mode (DEL on) the Long Delay (LD) configuration switch determines the time

span of the drying cycle. The Delay-Off time can be adjusted from 30-90

minutes (LD Off) or 2-6 hours (LD On) using the DELAY OFF control.

The Low Temperature Cutoff (LTC) option is typically used on snow melting

systems with limited output capacity where melting cannot be maintained at

very low temperature. If selected, the snow sensor will clear a trigger below

5°F (-15°C) even if snow is still falling. It will resume normal operation

above 9°F (-13°C). However, the sensor will remember if it was triggered

before the drop below 5°F or if snow was detected during the cold period. If

so, the sensor will execute one Delay-Off cycle when the temperature rises

above 9°F in order to melt any snow left behind during the cold period. This

is referred to as RECOVER mode. Care should be exercised in using this mode as the potential

exists for ice to be formed on the melting surface.

The DS-2C precipitation sensor is very sensitive and can detect a single snow flake or rain drop. However,

if the DS-2C is mounted in an area susceptible to high winds, overhanging trees, or blowing ground snow,

nuisance triggering may occur. While proper placement is the best remedy, the SENSITIVITY control can

also be used to reduce nuisance triggering. An internal timer checks the precipitation sensor for moisture

and compares cleared time with triggered time. The highest sensitivity

setting (toward MORE) triggers on first detection. As the control is

adjusted clockwise precipitation must be detected for a longer period to be

considered valid. The lowest sensitivity setting (toward LESS) requires

120 seconds of detection before the unit triggers. If a trace amount of

snow blows onto the grid from a drift or overhang it will likely be melted

and evaporated in less than a minute. Similarly, a very light snowfall may also clear quickly from the grid.

If these conditions should be ignored by the sensor the SENSITIVITY control can be adjusted as required.

However, to prevent non-triggering during a true event, it is recommended that the user start at highest

sensitivity (MORE), then adjust while monitoring operation over time.

THE UNIT MUST BE IN STANDBY/RESET TO CHANGE CONFIGURATION SWITCHES

L'appareil doit être en mode STANDBY/RESET pour modifier commutateurs de configuration

3

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