tekmar 667 Snow Detector & Melting Control User Manual

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Start Button on the Control

The snow melting system is enabled by pressing the Start button on the control while
in the View menu. The control then displays the RUN TIME setting to allow the user
to adjust it. Once the snow melting system is enabled, the word STRT is displayed for
at least 5 seconds in the STATUS item while in the View menu. If the Start button on
the control is pressed while the system is already melting and up to temperature, the
running time counter is reset to the RUN TIME setting.

Remote Start / Stop Module 039

The snow melting system is enabled by pressing the button on the front of the 039.
While the zone is coming up to temperature, a green indicator light flashes on the front
of the 039. Once the zone is up to temperature and the RUN TIME is counting down,
the green indicator light on the front of the 039 is on solid.

Remote Display Module 040

The snow melting system is enabled by pressing the

▲ button on the 040 while in

the View menu. The 040 then disp lays the RUN TIME setting to allow the user to
adjust it. Once the snow melting system is enabled, the word STRT is displayed for at
least 5 seconds in the STATUS item while in the View menu.

External Melt Demand (DIP switch set to Melt Demand)

The snow melting system is enabled when a voltage between 24 and 240 V (ac) is
applied across the Melt/Idle Demand terminals (15 and 16). An external melt demand
must be present for at least 4 seconds in order to start the snow melting system. If
the RUN TIME reaches 0:00 and the external melt demand is still present, the control
continues melting until the external melt demand is removed or the system is other-
wise stopped.

Note: This operation only occurs if the Idle Demand / Melt Demand DIP switch is set
to the Melt Demand position.

Menu

Item

Start

Stop

Start / Stop

Stop

Start

Idle Demand

Melt Demand

Idle Demand

Melt Demand

Melt / Idle

Demand

24 to 240 V (ac)

AUTOMATIC MELTING ENABLE (Snow / Ice Sensor 090)

The 667 can use the Snow / Ice Sensor 090 to provide an automatic melting enable signal to start the snow
melting system. The control continually monitors the 090 for the presence of moisture. Once moisture is
detected, the Water pointer is displayed in the LCD and the snow melting system is enabled.

Water Detection Sensitivity (SENSTVTY)

The 667 has a sensitivity setting which compensates for varying outdoor conditions which could affect
how the moisture detector in the 090 interp rets the p resence of moisture. This adjustable setting is
available through the SENSTVTY item in the Adjust menu of the control. As snow becomes contami-
nated with dirt, and as the sensor itself becomes dirty, the control may incorrectly indicate the presence
of water. If this condition occurs, clean the surface of the sensor and / or turn down the SENSTVTY
setting. If the snow in your area is very clean, the SENSTVTY setting may need to be increased before
snow is detected. If AUTO is selected, the control automatically adjusts the sensitivity level used to
detect moisture.