10-10
Page 53
2008-10-01
7. CONTROLS
A.
GENERAL
(1) NORTEC humidifiers all accept on/off controls for their security loop. Many NORTEC
humidifiers can also accept modulating or transducer signals for control (See the
features section for each specific model).
CAUTION
REGARDLESS OF SELECTING ON/OFF OR MODULATING CONTROL
METHOD, NORTEC HUMIDIFIERS MUST HAVE CLOSED CIRCUIT
ACROSS ITS ON/OFF SECURITY LOOP CONTROL TERMINAL TO
OPERATE. NORTEC HIGHLY RECOMMENDS THE USE OF A HIGH
LIMIT HUMIDISTAT AND AN AIR PROVING SWITCH IN SERIES FOR
THIS FUNCTION.
B.
ON/OFF CONTROLS
(1) On/Off controls are used in all NORTEC humidifier security loops. The digital
humidistat can also be used as a space humidity controller. These controls include:
(a) Air Proving Switch – duct mounted, pressure differential switch, adjustable set
point from 0.07 IWC to 12.0 IWC, good for positive, negative or differential
pressure applications, stops humidifier if duct air pressure is not sensed. Turns
humidifier off if air handler fails.
(b) Duct Mounted Digital Humidistat – control or high limit, adjustable set point from
15-90% rh with accuracy fixed at
±
3% at 25°C
,
operating range of 0-95% rh, closes
on humidity drop for control and opens on rise for high limit duct application.
(c) Wall Mounted Digital Humidistat – control or high limit, adjustable set point from
15-90% rh with accuracy fixed at
±
3% at 25°C
,
operating range of 0-95% rh, closes
on humidity drop for control and opens on rise for high limit application.
(d) On/Off Controls Supplied by Others – Can be used as long as they have a dry set
of contacts capable of passing a 24-VAC, 2-A maximum signal.
C.
MODULATING CONTROLS
(1) Modulating Controls are used to send a modulating demand signal to the NORTEC
humidifier. Different models can accept different signals (see features section for each
specific model) NORTEC supplied controllers send a 0-10 VDC demand signal. This
signal can be used as a control and in some models can also be used as a modulating
high limit. These controls include:
(a) Wall Mounted Digital Humidistat with Integrated Sensor – control or high limit,
adjustable set point from 15-90% rh with accuracy fixed at
±
3% at 25°C, outputs a
0-10 VDC signal.
(b) Wall Mounted Digital Humidistat Without Sensor – control or high limit, adjustable
set point from 15-90% rh with accuracy fixed at
±
3% at 25°C, outputs a 0-10 VDC
signal. Requires a remote transducer sensor supplying a 2-10 VDC signal.
(c) Duct Mounted Digital Humidistat With Sensor – This package comes with both a
remote sensor and a wall mounted controller without sensor. Control or high limit,
adjustable set point from 15-90% rh with accuracy fixed at
±
3% at 25°C, outputs a
0-10 VDC signal.
Summary of Contents for NHPC
Page 1: ...2538144 B NH Series NHTC NHPC ELECTRODE STEAM HUMIDIFIER Engineering Manual TM ...
Page 9: ...10 00 Page 1 2008 10 01 10 00 INTRODUCTION ...
Page 10: ...10 00 Page 2 2008 10 01 Figure 1 NHTC ...
Page 13: ...10 00 Page 5 2008 10 01 Figure 2 Optimum Boiling Time Figure 3 Conductivity ...
Page 18: ...10 00 Page 10 2008 10 01 Figure 6 Typical NHRS Installation Sheet 1 of 2 ...
Page 19: ...10 00 Page 11 2008 10 01 Figure 7 Typical NHRS Installation Sheet 2 of 2 ...
Page 20: ...10 10 Page 12 2008 10 01 10 10 HUMIDITY STEAM ABSORPTION AND DISTRIBUTION ...
Page 35: ...10 10 Page 27 2008 10 01 Figure 2 Psychrometric Chart ...
Page 64: ...10 10 Page 56 2008 10 01 Figure 30 NORTEC OnLine Monitoring ...
Page 71: ...10 20 Page 63 2008 10 01 10 20 SPECIFICATIONS ...
Page 81: ...10 30 Page 73 2008 10 01 10 30 SUBMITTALS ...
Page 86: ...10 30 Page 78 2008 10 01 Figure 2 Primary Line Voltage Wiring to Unit ...
Page 87: ...10 30 Page 79 2008 10 01 Figure 3 Physical Data NHTC NHPC 005 030 ...
Page 88: ...10 30 Page 80 2008 10 01 Figure 4 Physical Data NHTC NHPC 050 100 ...
Page 89: ...10 30 Page 81 2008 10 01 Figure 5 Physical Data NHTC NHPC 150 200 ...
Page 96: ...10 30 Page 88 2008 10 01 Figure 12 In Duct AHU Installation With Mounting Frame Installation ...
Page 98: ...10 30 Page 90 2008 10 01 Figure 13 In Duct AHU Installation With Mounting Frame Installation ...
Page 100: ...10 30 Page 92 2008 10 01 Figure 16 Atmospheric SAM e Adapter Dimensions ...
Page 101: ...10 30 Page 93 2008 10 01 Figure 17 Atmospheric Steam Header and Adapter Configuration ...
Page 102: ...10 30 Page 94 2008 10 01 Figure 18 Physical Data for Remote Mounted Blower Pack ...
Page 103: ...10 30 Page 95 2008 10 01 Figure 19 Physical Data Units with Optional Built On Blower Packs ...
Page 104: ...10 30 Page 96 2008 10 01 Figure 20 Physical Data Units with Optional Built On Blower Packs ...