Xerox 555 - Manual (Page 82)

A-16 WorkCentre Pro 555/575
Notice: The Ringer Equivalence Number (REN) assigned to each
terminal device provides an indication of the maximum number of
terminals allowed to be connected to a telephone interface. The
termination on an interface may consist of any combination of devices
subject only to the requirement that the sum of the Ringer
Equivalence Numbers of all the devices does not exceed 5.
This digital apparatus does not exceed the Class A limits for radio
noise emissions from digital apparatus set out in the Radio
Interference Regulations of Industry Canada.
Cet appareil numérique est conforme aux limites d'émission de bruits
radioélectriques pour les appareils de classe A stipulées dans le
Règlement sur le brouillage radioélectrique du ministère des
Industries du Canada.