tekmar 664 Snow Detector & Melting Control Installation - Manual (Page 11)

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Section D2: Snow Melting Disable
The snow melting system can be disabled manually or automatically. A melting disable signal applied to the control takes both zones
out of the Melting mode. Once the snow melting system is disabled, the zone(s) operates in the Idling mode. The Idling mode allows the
zone(s) to be either operated at a lower temperature or turned off.
MANUAL MELTING DISABLE
A manual melting disable signal requires the user to manually stop the snow melting system and can be provided from the Stop
button on the control, Remote Start / Stop Module 039, Remote Display Module 040, or an external idle demand.
Stop Button on the Control
The Stop button on the control can be used to stop the snow melting system. The snow melting system is disabled by pressing
the Stop button on the control while in the VIEW menu. Once the snow melting system is disabled, the word STOP is displayed for
5 seconds in the STATUS item of the appropriate zone while in the VIEW menu.
Remote Start / Stop Module 039
A Remote Start / Stop Module 039 can be used to stop the snow melting system. The snow melting system is disabled by
pressing the button on the face of the 039. When the system is stopped, a solid red indicator light is displayed on the face of the
039 for fi ve seconds. If the snow melting system is disabled while there is still an external melt demand for snow melting, the 039
displays a solid red indicator light until the external demand is removed.
Remote Display Module 040
A Remote Display Module 040 can be used to stop the snow melting system. The snow melting system is disabled by pressing
the
▼ button on the 040 while in the VIEW menu. Once the snow melting system is disabled, the word STOP is displayed for 5
seconds in the STATUS item of the appropriate zone while in the VIEW menu.
19 20
Melt / Idle
Demand
24 to 230 V (ac)
L
N
Idle Demand
Melt Demand
External Idle Demand (DIP switch set to Idle Demand)
The snow melting system is disabled when a voltage between 24 and 230 V (ac) is
applied across the Melt / Idle Demand terminals (19 and 20). An external idle demand
must be present for at least 4 seconds in order to stop the snow melting system.
Note: This operation only occurs if the Idle Demand / Melt Demand DIP switch is set to
the Idle Demand position.
If the snow melting system is placed into Idling mode by an external idle demand, then
a manual melting enable signal is applied, the idle demand is overridden until either the
running time has expired, a stop signal is given, or the external idle demand is removed
and reapplied.
AUTOMATIC MELTING DISABLE (Snow / Ice Sensor 090)
The Snow / Ice Sensor 090 can be used to automatically disable the snow melting system. Once the 090 is dry, the Water pointer
turns off in the LCD. The zone 1 slab temperature has to be at least the zone 1 slab target temperature for a minimum of thirty
minutes in order for zone 1 to turn off. If a manual melting disable signal is applied and the 090 is dry, the snow melting system
turns off immediately.