Stulz DAH - Main Power and Control Wiring; Wire Sizing - Control Box to Humidifiers

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Series GEN 2 Ultrasonic Humidifier IOM Manual
humidifier, include and air gap, and the end must not be obstructed.
Main Power and Control Wiring
For wiring, refer to the electrical drawing supplied with your unit to determine the total number of
interconnecting conductors required for your system and for the proper wire terminations.
For internal wiring of the humidifier, see the Electrical Diagrams.
NOTES
Wiring terminations may become loose during transit of the equipment, therefore, verify all wiring
terminations are secure prior to operation. Provisions must be made to ensure the humidifier only
operates when there is air flow.
Verify that the main power supply to the control box coincides with the voltage, phase and frequency
information specified on the nameplate. The nameplate also provides the full load amps (FLA), the
current that the unit will draw under full design load, the minimum circuit ampacity (MCA) for wire sizing,
and the maximum fuse size (MFS) for circuit protection. For safety, the power source must be provided
with a circuit breaker.
Ensure a ground is connected to the unit. The humidifier is rated to operate with a nominal input of
48VDC. To maintain warranty coverage, never allow the humidifier input voltage to exceed 51 volts as
damage will occur to the transducers and print plates.
Wire Sizing — Control Box to Humidifiers
The table below indicates the correct electrical wire sizing from the control box to the humidifier power
cable for three different distances. All wire sizes listed are for stranded, THHN or NTW wire only. (Do not
use solid conductor wire.) For distances over 75 feet, contact Product Support for assistance by fax
(301) 620-1396, telephone (888) 529-1266 or E-mail (parts@stulz-ats.com).
In addition to the above power wires, humidifiers controlled by the Ultra-Series control box use
RJ45/CAT5 data communication cables, daisy chained from the humidifier(s) to the control box.
The data communication cable is not to exceed 1000 feet total length from the control box to the last
humidifier. A termination resistor must be installed on the last humidifier as shown in the electrical
drawing provided with your unit.
CAUTIONS
The termination resistor is only to be placed on the last unit in the data communication string.
The power supply provided with the equipment is sized and selected based on the expected load. Do not
connect any additional loads to the control power supply.