User Guide

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GENERAL INFORMATION
The ATS 503 is designed to switch the on-board 120-volt appliances to
an alternate 120VAC power source such as an inverter or generato
r
when the alternate power source is energized.
The ATS 503 features include a rugged galvanized steel enclosure,
solid state printed circuit board construction, heavy duty PCB mounted
relays, a 20-30 second generator time delay, time delay
Enable/Disable, and compression lug wiring terminals with 5/32” hex
drive set screws for ease of wiring and safe, reliable operation.
The default power source is the shore line or utility power input “side”
of the switch.
The alternate power source or “Generator” input side of the switch will
“take command” of the switch when the alternate source is energized.
Refer installation and servicing of this product to qualified service
personnel. Technical or service information is provided solely for
use by licensed electricians and certified RV technicians. No
endorsement of technical expertise is expressed and/or implied.
User assumes all liabilities arising from use of this information.
WIRING INSTRUCTIONS
WARNING: RISK OF ELECTRICAL SHOCK OR BURNS.
Note: If using the ATS 503 in a single phase 120VAC supply system,
use connection terminals L2 and neutral for source input and load
output connections. Generator side transfer will not occur i
f
generator input terminals L2 and neutral are not energized.
Utility L1, Utility L2, Utility Neut., and Utility Aux are input terminals fo
r
connection to Shore line/ Utility power.
Gen L1, Gen L2, Gen Neut., and Gen Aux are input terminals fo
r
connection to the Generator or an alternate power source.
Load L1, Load L2, Load Neut., and Load Aux are output terminals fo
r
connection to the load panel or load circuits.
Jumpers NJ1, NJ2, and NJ3 bridge neutral and auxiliary terminals at
each source input and at the load output to provide 70 ampere neutral
return ampacity for use with “in-phase” 120VAC supply sources.
ALL CONNECTIONS MUST MEET TORQUE SPECIFICATIONS
SHOWN ON THE WIRING LABEL LOCATED ON THE ATS 503
INSIDE COVER OR AS LISTED BELOW.
Terminal Torque Specifications
BONDED EQUIPMENT GND. CU 6-14; COPPER WIRE ONLY.
TORQUE RATING: 35 IN. LBS.
ALL OTHER TERMINALS TORQUE RATINGS:
AWG CU INCH-POUNDS
10 – 14 35
8 40
4-6 45
2 50
FIELD WIRING CONDUCTORS – INSULATION RATING 90°C,
MINIMUM.
COPPER WIRE ONLY.
WIRE SIZE OF FIELD WIRING CONDUCTORS- USE AMPACITY OF
WIRE RATED AT 75 °C. MAXIMUM.
WARNING: RISK OF ELECTRICAL SHOCK OR BURNS.
N
o user serviceable parts inside.
Refer installation and servicing to qualified service personnel
WARRANTY INFORMATION
Reference the enclosed Parallax Power Supply Warranty Policy or downloa
d
the policy at: http://www.parallaxpower.com/warranty
Parallax Power Supply
Phone: [phone] • Fax: [phone]
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