Pure Humidifier INTAC, Инструкция по установке и руководство по обслуживанию

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9
TRI - PROBE OPERATION
Humidifier models that run on tap water will use the dissolved mineral content and associated
conductivity of the water to sense the water at discrete levels near the top of the tank. The Tri
- Probe
water detect circuit is based on the level detection of a 6KHZ (approximately) square wave with nominal
Vpp of 1.0 volts. The voltage is applied to the probe so that when a probe tip is in contact with the water
a circuit is completed through the water to tank ground and a resistance value can be calculated. If a
probe is not in contact with the water then the circuit is not complete and the controller sees a high
resistance. Similarly when the water level being sensed is free of minerals, and therefore
nonconductive, the controller will measure a large resistance and will not “see” the water level. The
water in the tank must have a resistance of less than 13 kOhm/cm in order for the controller to logically
say “yes” there is water at this probe level.
The three probes are used to control the fill valve and heaters in the following manner
1) The water level falls as steam is generated
2) The middle probe eventually loses contact with the water
3) The fill valve is energized
4) The water level rises up to the top probe
5) After 5 continuous seconds (fill delay) of water contact with the top probe the fill valve closes
6) If at anytime the bottom probe is not in the water the heaters are de - energized and will remain off
Humidifier models that use reverse osmosis or deionized water will use a float switch as a low water
cutout and a mechanical float valve for controlling the makeup water.
AUTOMATIC DRAIN CYCLE
Humidifier models that run on tap water will accumulate minerals in the water as the water is boiled
away . Sometimes immediately but always eventually the dissolved minerals will reach saturation and
begin to precipitate out of the water. For this reason it is necessary to drain the tank down periodically
to reduce the accumulation of minerals and extend the time period between cleanings. The process the
INTAC
®
goes through to accomplish this is called the Automatic Timed Drain.
By default the humidifier begins counting run time whenever the humidifier output is greater than 0%.
The time it must count up to before starting the cycle is called the Drain Interval (MENU 203). When the
Drain Interval time is reached the humidifier will enter the cool down phase where the fill valve turns on
for a specified amount of time (MENU 204) or until a certain tank temperature is reached (MENU 205).
When the cool down phase ends the drain valve is energized and will remain energized for the Drain
Duration (MENU 202).
When 3/4 of the Drain Duration time has expired, the fill valve will turn on to stir
the minerals on the tank bottom. When the drain duration time elapses, the drain valve will turn off and
the fill valve will remain on until the tank is refilled. The Drain Duration (MENU 202) is factory set to the
amount of time it typically takes for the tank to completely drain down. The Drain Interval (MENU 203)
should be adjusted to minimize observed mineral accumulation.
Alternately the Automatic Timed Drain can be controlled with an external switch or relay if it is desired to
control the timing of this feature. Consult the factory to receive instructions on how to change the factory
menu settings.