To ensure safe operation and service of the tester, follow these
instructions. Failure to observe these warnings can result in
severe injury or death.
• RT390 is designed for use with North American 3-wire grounded
120V electrical outlets. DO NOT connect to higher voltage
electrical supplies.
• Only use the tester with the supplied NEMA-rated cord.
• Prior to use, always verify tester operation by testing on a known
live and correctly wired electrical outlet.
• DO NOT attempt an AFCI testing event on a circuit with powered
ON equipment or devices. Remove or power OFF prior to testing.
• DO NOT use if the tester appears damaged in any way.
• The tester is intended for indoor use only.
• To reduce the possibility of erroneous readings:
• All appliances or equipment on the circuit being tested should
be disconnected.
• Turn off or move away from equipment which cause
electromagnetic interference.
• DO NOT attempt AFCI, GFCI, 30mA ground fault testing, or
load testing on an incorrectly wired outlet. Consult a qualified
electrician to resolve wiring problems.
• This tester only detects common wiring problems. ALWAYS consult
a qualified electrician to resolve wiring problems. The device:
• Will not indicate quality of ground.
• Will not indicate two hot wires in a circuit.
• Will not detect a combination of multiple wiring faults.
• Will not indicate reversed ground and neutral.
• AFCI indicators produce characteristics that mimic some
forms of arcing. Because of this the indicator may give a false
indication that the AFCI is not functioning properly. If this occurs,
recheck the operation of the AFCI.
Risk of danger. Important information: It is important that
users of this tester read, understand, and follow all warnings,
cautions, safety information, and instructions in this manual
before operating or servicing this tester. Failure to follow
instructions could result in death or serious injury.
Risk of electric shock.
Read instructions.
WARNINGS
SYMBOLS ON TESTER
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