System Preparation and Configuration
1-4 ◆ Section 1: Installation Basics DS1000 Hardware Manual
Single Line Telephone REN Limitations
Please note the following when installing single line telephones:
● The total Ringer Equivalence Number (REN) per system cannot exceed 4.
● The total REN per analog port cannot exceed 4.
● Ringer Equivalence is cumulative.
By default, all analog telephones ring simultaneously for outside calls (as do all analog telephones con-
nected to the same port). This means you must add up all analog telephones connected to the system (includ-
ing all those connected to the same port) and ensure that the total combined REN is 4 or less.
Note: A REN of 1 is the normal for an industry standard 2500 set with electromechanical ringer. Many
phones with electronic ringers have significantly lower RENs.