Specifications

Page 12 • DRI-STEEM CRUV Electric Humidifier Installation, Operation, and Maintenance Manual
Wiring
Figure 12-1:
Field wiring requirements
Fused
disconnect
(provided by
installer)
Power
supply
(provided
by installer)
OM-7552
Notes:
• Control wiring and power wiring must be run in
dedicated or separate earthed metal conduit, cable
trays, or trunking.
• Separate the line voltage wiring from low voltage
control circuit wiring when routing electrical wiring
inside the humidifier cabinet.
• Do not use chassis or safety grounds as current-
carrying commons. Never use a safety ground as a
conductor or neutral to return circuit current.
Installation
Control
cabinet
Humidifier field wiring
All wiring must be in accordance with all governing codes, and with
the humidifier wiring diagrams. The diagrams are located inside
the removable subpanel cover on the right side of the humidifier
cabinet. Power supply wiring must be rated for 220 °F (105 °C).
When selecting a location for installing the humidifier, avoid
areas close to sources of electromagnetic emissions such as power
distribution transformers.
The fill valve, drain valve, probes, and temperature sensors use
Class 2, 24 VAC power.
The use of semiconductor fusing sized per the National Electric
Code is recommended with the SSR option.
Grounding requirements
The approved earth ground must be made with solid metal-
to-metal connections and must be a good conductor of radio
frequency interference (RFI) to earth (multistranded conductors).
Ground wire should be the same AWG (mm
2
) size as the power
wiring or sized per NEC requirements.
Proper wiring to prevent electrical noise
Electrical noise can produce undesirable effects on electronic
control circuits, which affects controllability. Electrical noise is
generated by electrical equipment such as inductive loads, electric
motors, solenoid coils, welding machinery, or fluorescent light
circuits. The electrical noise or interference generated from these
sources (and the effect on controllers) is difficult to define, but
the most common symptoms are erratic control or intermittent
operational problems.
Important:
• For maximum EMC (electromagnetic compatibility)
effectiveness, wire all humidity, high limit, and airflow controls
using multicolored shielded/screened plenum-rated cable with
a drain wire for the shield/screen. Connect the drain wire to the
shield/screen ground terminal with wire less than 2" (50 mm) in
length.
• Do not ground shield at the device end.
mc_061610_0625-CRUV
WARNING
Electric shock hazard
Only qualified electrical personnel
should perform field wiring installation
procedures. Improper wiring or contact
with energized circuits can cause property
damage, severe personal injury, or death
as a result of electric shock and/or fire.
Do not remove the humidifier electrical
panel cover or the heater terminal cover
until electrical power is disconnected.
Contact with energized circuits can cause
property damage, severe personal injury,
or death as a result of electrical shock.
mc_062310_0629
mc_062310_0630-CRUV