Nortec NH Series installation manual 10V Digital Humidistat Sensor Calibration, Term Definitions

	Table 4. Term Definitions
Term	Definition
RATED AMPS	Refers to amps listed on the humidifier specification label.
SHORT CYCLING	When the ‘on time’ of the humidifier is less than ten minutes upon a call for humidity. To correct
	short cycling, all humidifiers have a capacity adjustment which allows the output of the humidifier to
	be reduced as low as 20% of rated output, thus extending the ‘on time’ required to maintain output.
FOAMING	This phenomenon can occur in water when the impurities, already in the water, reach an excess
	concentration as result of boiling away pure water, and the continued boiling action agitating the
	contained water. The humidifier electronics are designed to prevent this occurrence, although in
	extreme cases water will foam with little concentration making it necessary to have the drain time of
	the water, contained in the cylinder, increased. Foaming is normally caused by short cycling, a
	restricted drain, or back pressure. The foam generated in these instances, is conductive and may
	lead to a false full cylinder indication if the level of the foam approaches the top of the cylinder.
BACK PRESSURE	This can be caused by restriction of steam flow caused by long steam runs; improperly sloped
	steam lines; elbows changing the direction of the steam flow from horizontal to vertical without a
	drain leg, any plumbing detail allowing the accumulation of condensate; undersized steam line;
	improper steam distributor; downward air flow onto the distributor creating excess static pressure at
	the steam outlets; or high static pressure ducts (not probable). To overcome excess static pressure
	in the duct, a fill cup extension kit should be used. In downflow applications, a downflow distributor
	should be used but in some cases the fill cup extension will also be required.
RESET UNIT	To reset the humidifier, the ON/OFF switch at the front of the humidifier should be switched to the
(HUMIDIFIER)	OFF position for a minimum of five seconds and then switched back to the ON position.
MONITORED LEG	Refers to the primary wire to the cylinder which loops through the current sensing device on the
	driver PCB. This wire is terminated at the red cylinder plug at the cylinder. Units with six primary
	wires to the cylinder will monitor only one of the two wires, terminating with red plugs.
CONDENSATE	Refers to steam that has condensed to a liquid.

6.0-10V DIGITAL HUMIDISTAT SENSOR CALIBRATION

A.PROCEDURE

(1)The humidity sensor is factory calibrated, however, it can be field recalibrated. The calibration routine can be accessed by pressing and holding down the option button for five seconds. A new screen will appear with the calibration adjustments.

(a)Press the up or down buttons until calH appears on the LCD screen.

(b)To adjust the calibration press the Option button. The screen should load to display the current calibration trim.

(c)The calibration trim can be adjusted by pressing the up or down buttons to the desired level and then pressing the option button to confirm the settings.

(d)Press the Power button to return to the normal display.

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